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56% 4 SMITHSONIAN MISCELLANEOUS COLLECTIONS. _ 254.0 ——________
Sr NOP S LS
or
AMERICAN WASPS.
BY Dr. HENRI DE SAUSSURE,
OF GENEVA, SWITZERLAND.
SOLITARY WASPS.
) WASHINGTON: SMITHSONIAN INSTITUTION.
DECEMBER, 1875.
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ADVERTISEMENT.
Tue present publication is the first part of a Synopsis of American Vespide or Wasps, prepared by Dr. Henri De Saus- sure of Geneva, Switzerland, one of the highest living authorities on the subject.
This work relates to the ‘‘ Solitary Wasps,” and has been the result of many years of careful study and patient investigation. Unforeseen events have occurred to delay its publication, in addi- tion to the loss of time occasioned by the necessity of transmit- ting the proofs and revises to the author in Europe.
In the introduction will be found suggestions by the distin- guished author as to the philosophy of points of natural history, well worthy the attention of the general students of this branch of science, and the whole work will doubtless be considered a valuable addition to the sources of knowledge on entomology.
The Institution acknowledges the important aid rendered in the translation of the work into English, its careful preparation for the press and the revision of the proof-sheets, by Mr. Edward Norton of Farmington, Conn., whose services have also been acknowledged in the annexed dedication by the author.
JOSEPH HENRY, Secretary S. I.
SMITHSONIAN INSTITUTION, Wasuineton, December, 1875.
PHILADELPHIA COLLINS, PRINTER.
(il )
DEDICATION.
To Mr. Epwarp Norton. Sir :—
I am desirous of dedicating to you this first attempt to draw up a Hymenopterological Fauna of North America. The un- flagging interest you have kindly taken in this work emboldens me to hope that you will accept my offering.
The readiness with which you placed at my service your col- lections, and the assistance of your valuable instructions, were already sufficient claims to my gratitude. Your kindness in taking upon yourself the task of translator makes me feel more strongly the extent of my obligations to you.
It is for me a subject of regret that my imperfect acquaint- ance with the English language has not permitted me to relieve you from the trouble of this work. Had I been capable of composing this book’ in the idiom in which it is to appear before the public, the many hours of enjoyment I have had in writing it would not be contrasted with the many tedious hours it is likely to occasion you.
Beside the peculiar charm which the study of nature ever possesses, the drawing up of this monograph has wafted me in thought to those regions of the New World which have, since I was a child, allured me with an irresistible spell. While conning over my insects, many a remembrance has loomed before my mind, and transported me to those thought-inspiring and soul- stirring scenes of your magnificent country. As a Swiss, I felt
( iii )
iv DEDICATION.
a secret pride in reflecting that its institutions are analogous to those of my own dear country, and that the grandeur of its physical scenery and the intellectual life which animates all classes of its people, have their counterpart in Helvetia.
For me it is a source of satisfaction to be able to contribute, in my humble sphere, to the extension of the physical knowledge of that part of the American continent, whose natural riches we are daily more and more able to appreciate, thanks to the untiring zeal of its scientific men.
I trust, sir, you will deign to read these lines with an indul- gence equal to the sincerity with which they are addressed to you, and that you will see in them a pledge of my gratitude and
devotedness. : HENRI De SAUSSURE.
GENEVA, SWITZERLAND, 1 May, 1863.
PREFACKH.
I PUBLISHED in 1852 my Monograph on the Solitary Wasps;} which forms the first volume of my Studies on the Family of the Vespide.? As soon as that work was printed, I perceived that it was very imperfect.
T was still a mere student when I composed the greater part of this book; it bears too evident marks of its premature publi- cation. I consequently felt the necessity of correcting and com- pleting it by means of a Supplement which occupies the greater part of the third volume of the Studies on the Family of the Vespide. This, however, was insufficient.
To the imperfections in the MS. of the work, attributable to my inexperience, were added those of the form. I had the misfortune to fall into the hands of a printer who not only delayed for years the publication of the work, but who also executed it in a shame- ful manner, neglecting to make proof corrections, and printing the notes in the midst of the text.
Having lost all patience with the delay and errors of the work, I turned my back on the social wasps and started for America, leaving to the care of my excellent and worthy friend, Dr. Siebel, who had often aided me with his skill and advice, the task of superintending the impression. Two years after, on my return to Hurope, I found that only three or four sheets had been printed, and that the third volume was only on the eve of being finished, and it was not until 1857 and 1858 that the volume on the social wasps was completed, by the appearance of the general part, in which were developed the facts concerning the nidification of these insects, of which a summary alone had appeared in 1853 and 1854, in the explanation of the plates, and in a special paper. But
— ———$_______— ~ a —,
' Monographie des Guipes Solitaires. Gendve, Paris. 2 Etudes sur la Famille des Vespides, 3 vols. and atlas.
(v)
vi PREFACE.
during the three years, while the manuscript had lingered in the hands of the printer, there had appeared a memoir, by Dr. Mobius, on Wasps’ Nests, so that my work, at the time of its publication, was in arrear of science.*
To these contingencies I must add the death of the artist M. Vaillant,’ of so interesting memory, during the publication of the first volume. The succeeding draughtsmen, by whom I replaced him, were far from equalling him, and have often produced infe- rior, sometimes even bad drawings.?®
It will be easily understood that all these vicissitudes have not a little contributed to render the work defective. From the very first, I have felt the necessity of recasting it. But as I could not undertake fresh journeys to visit the collections in distant centres, Paris, London, etc., I have adopted another method, which consists in correcting and completing my studies on the Family of the Vespide by means of successive memoirs, result- ing from the study of collections, which are kindly communi- cated to me.* All these works, together, will perhaps enable
me one day to recompose a general work. An excellent oppor-
1 When, at length, the work was completed by the tardy appearance of the general part of the 2d volume, Mr. Gerstacker spoke of this general part in his annual report on the progress of Entomology (Troschel’s Archives), calling it, 1 know not for what reason, the commencement of a fourth volume. He reproached it disparagingly for not noticing recent works. True it is, he could not guess that it was an old laggard which had been some years in press.
2 Mr. Vaillant was the artist attached to the scientific exploration of Algeria.
3 ‘The drawings of the Pl. XVI, of Tome I, are in particular very bad.
4 I have thus composed the following memoirs, forming, as it were, a supplement to my Studies on the Vespide :—
1. Description de quelques nouvelles Especés de Vespides du Musée de Lon- dres. (Revue de Zoologie, VII, 1855.)
2. Nouveaux Vespides du Mexique et de l’ Amérique septentrionale. (Revue de Zoologie, IX, 1857.)
2, Note sur la Famille des Vespides. (Ibid., X, 1858.)
4, Note sur les Polistes Americains. (Ann. Soc. Ent. de France, 1857.)
5. Description de quelques Vespides nouveaux. (Ibid., 1857.)
6. Bemerkungen tiber die gattnug Vespa. (Entomol. Zeitung von Stettin, 1857.)
7. Sur divers Vespiaes Asiatiques et Africains du Musée de Leyden. (Ibid., 1862.)
PREFACE. Vil
tunity of extending my studies on the Wasps offered itself when the Smithsonian Institution was pleased to commission me to establish the,fauna of the Hymenoptera of North America. I was already in possession of numerous materials for the drawing up of such awork. J had brought from that continent considerable collections, the fruits of my explorations in West India, Mexico, and the United States. I had likewise acquired collections of Hymenoptera in my passage through this latter country, of Mr. Rathvon (Lancaster, Pa.), Mr. Fuch (Tennessee), and others. Prof. Haldemann kindly made me a present of the remnants of his splendid collection, unfortunately almost destroyed. ‘To these materials which I had got together as I went along, there came to be added later, the collections which the Smithsonian Institu- tion forwarded me from different regions of the United States.’ But I owe a special mention to my friend Mr. Edw. Norton, of Farmington, Connecticut, an excellent entomologist, who afforded me the most valuable assistance for the work to which these lines serve as an introduction, and who with extreme kind- ness offered to undertake the translation of this volume himself. Finally, I have, moreover, received some parcels of insects direct from divers friends, especially from Tennessee, from Engineur de Freudenreich Falconnet, Engineer on the Nashville Railroad, and since then Major in the Confederate Army; from California, through Mr. Berton, Swiss trader at St. Francisco, and by Mr. Sutter.
Notwithstanding all these contributions, the collections which I myself brought from America still form the staple of my mate- rials; but these subsequent additions are very useful complements. I, therefore, avail myself of this opportunity to thank publicly
1 Hymenoptera from Rock Island, South Illinois, collected by Kennicott. i u from Illinois, collected by Walsh. es s from Lake Superior, collected by L. Agassiz. ae ne from Williamstown, Massachusetts, collected by S. H. Scudder. Ut Mt of the Cape St. Lucas, California, collected by Jolin Xantus. ue sf from Rio Peros River, collected by Capt. Pope, U.S. A., and various other Hymenoptera collected at Fort Tejon, California; English River, ete. The first five collections had been formed by individuals in the interest of science; the others by explorations carried on by order of government.
Vill PREFACE.
all the above-mentioned persons for the assistance which they have kindly afforded me. Among them I ought to name espec- ially, Prof. Henry, as director of the Smithsonian Institution, and Prof. Baird, who have always shown me the greatest kindness.
I ought, however, to inform the reader that, notwithstanding so much help, the work does not contain all the species of America. I myself possess divers individuals, which, without offering characteristics distinct enough to be described from one indi- vidual, nevertheless betray the existence of species yet unknown. Moreover, the larger part of the smaller species seem till now to have baffled the researches of collectors. I do not hesitate to affirm, that, had I been able to collect undisturbedly in the United States, I should very likely have brought back from that country a number of small species as considerable as that which I have brought from Mexico.
But it is in the natural progress of science to advance gradu- ally towards completeness; and consequently, it is the lot of books of science to grow old and become obsolete; and thus, in their turn, to give way to more complete works. I do not, there- fore, consider this monograph, incomplete as it may be, without its use. I am not one of those who suppose it possible to exhaust a subject of investigation. On the contrary, I am of opinion that in entomology, as well as in the other branches of science, nothing perfect, nothing absolutely complete, ean he accomplished, seeing that everything in nature is undefined. The naturalists who think the contrary, and who are induced constantly to put off the publication of their labors from believing they shall wholly complete them, sueceed but too often in losing the fruits of their studies; either because their writings grow oid while lying by, or because the authors are overtaken by death. The proper method in the study of nature is not that of per- fection, but, on the contrary, that of approximation. Because from approximation to approximation, we are always getting nearer exactness and completeness, without ever attaining extreme perfection. In that precisely consists the progress of science, and that also it is which gives to its horizon the depth of infinitude.
PREFACE. ix
The foregoing was written some years ago. In 1865 the manuscript of the memoir was sent to the Smithsonian Institu- tion.
Its publication was at first delayed by the pressure of other matter, then by an unfortunate fire which embarrassed the finances of the Institution, and lastly the slow delays below mentioned.
The book has been in the press several years, in consequence of the great loss of time caused by the transmission of the proofs from Kurope to America, and vice versa.
In consequence of this long period of waiting, I have been obliged to make a review of the manuscript in reference to the writings of various entomologists, especially those of Mr. Cresson, which have been published from year to year, and have changed the names of the species which I had described and have adopted the names given by this author. I have not been able, however, to take account of the more recent writings of Mr. Cresson, on the Hymenoptera of Texas, which only came to my knowledge when the printing of this book was almost finished.
The reader will excuse certain irregularities, consequent upon the difficulty of putting a work into perfect symmetry which was to be printed on the other side of the Atlantic. Hence the author has never had but a part of his work before his eyes at a time, during the long course of this publication. For example, it will be noticed in the synonymy that my work, ‘‘ Etudes sur la Famille des Vespides” is sometimes cited “‘ Ht. Vesp.,” sometimes only “Vespides.” So with the ‘Revue et Magazine de Zoologie,” it is sometimes cited ‘Rev. et Mag. de Zoolog.,” and sometimes simply “ Rev. de Zool.”
The larger part of the book was written in French, and has been translated and corrected by Mr. Edward Norton. I owe to this naturalist also various communications and frequent send- ings of insects, which have been of great use to me.
H. De SAUSSURE.
INTRODUCTION.
I Propose in this volume, not to give a general history of the Wasps of America, but only to lay the foundations of the fauna of the Vespide of that continent, principally of North America. I leave aside whatever concerns the habits of these insects, on which we have but insufficient information, and I shall confine ‘ myself to speaking of them with respect to the genera or species which offer salient peculiarities.
This work is not to be taken for a mere catalogue of species, of no further use than to satisfy curiosity. I think that modern zoology ought to tend towards another aim. The existence of species, the composition of fauna, their relations with the parts of the globe which they populate, are not merely accidental facts. In my opinion, we must therein detect the last material and tan- gible manifestation of physiological forces, elucidating the study of which belongs to the domain of the highest natural philosophy. By him who adopts this view of the subject, a far-searching study of species ought to be considered as one of the bases from which the search after the origin of species may start.
It would seem that in zoology we should take for a startine- point the actually existing forms in which life manifests itself, and to ascend from them up to the primitive stock; just as in geology, we start from the actual existing structure of rocks and from the external configuration of the soil, to follow up the concatenation of the ancient events which have brought about as a last result the present state of the earth’s crust.
The study of species ought especially to serve as a means of revealing to us their variations and the affinities between them. These affinities point to a common relationsh ip, which is to be explained only by a direct affiliation of the types. The study of
| | (xi )
xii INTRODUCTION.
forms combined with that of their geographical distribution, comes afterwards to throw light on the cause of the filiation which the graduated resemblances of the species serve to reveal to us. It shows that this filiation obeys laws which have also their regu- larity, in so far as they are intimately connected with the physical laws which hold sway in every region of our globe.
Toward these grand philosophical queries, zoology ought in our time to tend, and species should be studied with a view to the solution of such questjons. As in geology, the study of the actual existing state of the earth’s crust, and the appreciation of the phenomena that there take place, of the intimate trans- formation of rocks, of the mechanical disturbance of the layers, of their reconstruction under new forms, allows us to draw an inference by analogy as to the more aucient transformations, and the agents which have produced them; so the study of species, and of their actual existing transformations seems likely to enable ~ us to follow up the chain of these transformations to a point more or less close to their origin.
The definition of the first divergences observable in the perma- nent varieties which may be considered as nascent species, in order to ascend afterwards to the relationship of species separated by divergences more and more profound, such is, we deem, the point of view under which we should never neglect to study species.
Zoology, only when considered from this point of view is philosophical. It has not its aim in itself; it serves only as a means to sift questions of a higher order. Now entomology is precisely the one of the branches of zoology, in which the study of the filiation of species may become the most fruitful in results, either on account of the multitude of ramifications of general types and of the multiplicity of forms under which each type appears, or on account of the smallness of the breaks which sepa- rate genera and species, or also on account of the immense variety of forms and of the facility with which species seem to become modified in proportion as they spread over the surface of the globe in diverging ways. Thanks to all these causes, it is not difficult to find examples of every kind of filiation, not difficult either to follow over latitudes certain still recent modifications which allow us to draw an inference by analogy as to other
INTRODUCTION. xiii
modifications more profound because they are more ancient, than as to others of a degree still more advanced.’
As may be anticipated from what precedes, my principal pur- pose in producing this work is to study the American fauna with a view to its origin. But this is a work of time which can- not be completed off-hand. ‘The first thing to be done is to study the species carefully, to arrange them according to a good classification, and to describe their affinities. That is the funda- mental preparatory labor. Ido not pretend to overstep those limits in this monograph. The knowledge of the American fauna is not yet enough advanced to allow us to draw an infer- ence with certainty as to the affinities of the species among themselves so as to prejudge their filiation. However, I have made more than one remark on this topic, and I will hazard a few words on the matter when speaking of genera and species. But I reserve for another work the statement of comparisons which seem to me to cast some light on the dispersion of the Vespide on the surface of the globe and on the modifications which have been worked off under diverse latitudes; in other terms, on the origin of actual existing fauna.
The complex affinities of species, and still more the filiations which arise from these affinities, become obvious to the eye only when one has acquired a perfect knowledge of the species and genera of a fauna. ‘To seize them in all their extent, it is neces- sary to know, as it were, all the species of the group by heart in order to be able to take it in at a glance, or to examine at pleasure each part in the picture that one has formed in one’s memory. Only when one has attained this point in the study of a group, is it possible, from the inspection of a species, to feel its affinities; for they do not always appear in the more easily
1 Unfortunately, in our times the greater number of entomologists have deviated too far from this philosophical path. They have turned ento- mology into a sort of amusement which has for object the discovery of new species; which loses itself in minutie, and at the bottom of which there exists no thought. Thanks to this tendency, collecting has ceased to be the means, and has become the object. In becoming an amusement entomology has gradually lost caste; it has fallen into the hands of daw- Alers, and thus lost a part of its scientific character. This transformation has led men, who aim at reaching an elevated rank in science, to be too much inclined to withdraw from the field of entomology.
XIV INTRODUCTION.
appreciable characteristics. They often discover themselves in certain characteristics of appearance, which are at times of great importance, but which are not setzed at a glance, or in certain relationships of form, which a long practice teaches one to dis- tinguish easily, though they can scarcely be defined.
The first basis of philosophical zoology is the profound knowl- _edge of the detail of fauna. To give as complete an idea as possible of the fauna of the Vespipz of America is the purpose of this volume.
PLAN OF THE WORK.
The plan which I have decided on, in drawing up this work, is the following :—
I give, as much as possible, a complete description of the species which belong to the fauna of North America, considering as such all those which people the new continent to the north of the isthmus of Panama, including likewise the Antilles. This work is, therefore, more especially a monograph of the Vespidz of the United States, of Mexico, and of the Antilles. Besides, I have added, as a complement, a catalogue of all the species known till now in the rest of America, and have found it a great advantage in the classification, the method thus becoming more complete. Moreover, this plan allows me to enunciate views on the geography of insects, on the dispersion of the species, and on the modifications which take rise under the influence of diverse latitudes.
I have confined myself, among the species of South America, to cataloguing them, not having sufficient materials to make a monograph. However, for those of which I had the types beneath my eyes I have given Latin diagnoses, in order to describe them in a comparative manner with respect to the surrounding species, and, also, in order to complete my anterior studies on these insects, to review them and render the use more easy. ,
I think myself bound to add here, that, as to my method of description, I describe the species as far as possible in a relative manner. Descriptions made in an absolute sense have always appeared to me less useful, because they insist on many useless characteristics and often omit the most important. The reader
INTRODUCTION. XV
will not be surprised, therefore, at my not repeating, with respect to genera, the characteristics peculiar to every species or to the greatest number of them. In short, there are still other charac- teristics which I pass over, considering them rather useless either on account of their constancy (such as the presence of silky hairs on the tibise) or on account of their variableness, such as the color of the lower surface of the abdomen.
Descriptions are often made prolix by means of these super- fluous indications, and thus the essential characteristics are drowned in useless developments. In this way, precision. is diminished instead of being increased. Doubtless, here again nothing is.absolute. Certain isolated species may be sufficiently characterized by some salient traits, while others surrounded by very closely connected species, require minute descriptions.* The first condition of good comparative diagnoses resides in a wise co- ordination of the species which by way of exclusion may lead to choosing only between a small number of species. Though I do not like to find fault, I cannot, however, on this score, help com- plaining of the works in which the species, though described in an absolute manner (that is, by themselves and not comparatively with others) are jumbled up together without order, without division of genera, often in defiance of the most salient character- istics.
Such works, got up in a hurry, the plans of which are laid down with a view to the convenience of the authors and not for that of the readers, cause the latter to lose much valuable time with no great result. They do not come up to the precision now required by the progress of science, and they are therefore behind their time. The reader cannot occupy his mind with incomplete works, nor can he waste his time in striving to find out species which are notto be found out; for there is no doing impossibilities.
In most of my descriptions, I have been especially attentive to the forms and characteristics of the forms and carving, attributing
1 Absolute and very detailed descriptions ought, in my opinion, to be employed, when one describes species isolatedly, without knowing the most closely connected types (for instance, in the publication of geogra- phical expeditions). It isthe monographer’s duty to eliminate, from these descriptions, both the commonplace and the useless. But in a mono- graph, the species are to be examined in a comparative manner, and rela- tively to the adjacent types.
xvi INTRODUCTION,
to the color only a secondary importance, on account of its fre- quent variableness. However, there is nothing absolutely fixed in nature; the forms and the sculpture likewise vary within certain limits. Therefore the descriptions can be only averages deduced from a certain number of individuals. The description should represent, as it were, the algebraical formula of the species, or its ideal type. It is not required that this should tally with the individual, but, on the contrary, that it should represent the average of the characteristics of the ensemble of individuals. But in practice, the description can never be so perfect, since it is drawn from a certain number of individuals and not from the ensemble of the individuals that represent the species. It is for the reader to know how to seize the connection that exists between the description and the heterogeneous individuals which he may have beneath his eyes. Ina word, my method of description aims above all at generalizing, and requires that the reader should generalize likewise. It can hardly suit the amateur inclined to lose himself in a multiplicity of details, for whom the collection takes the place of nature, and for whom the determination of an individual is the final purpose of the study of a species.
From the principles just laid down, it follows that in the extreme subdivisions of genera, I have usually preferred the characteristics taken from the form to those taken from the color. Undoubtedly it is less convenient for the reader, for the natural method is always less easy to follow than the empirical systems; never- theless, I think that it is preferable to proceed in that wise, for whatever may be done to seek the natural method, a large portion of empiricism is sure to remain, as I shall endeavor to show in the study concerning the filiation of the species. We cannot, therefore, abstain too carefully from classification of empirical elements.’ .
1 It is necessary to observe on this head that no absolute rule can be laid down as to the subordination of characteristics. To be sure, forms varying less than colors, they offer, in general, characteristics more im- portant than the latter; but there is, however, now and then a case in which the colors are more fixed than certain forms, and assume a real importance—for instance, as being the stamp peculiar to a certain geo- graphical zone. Thus, the division Hypodynerus (genus Odynerus), which depends greatly on the colors and facies, and which eomprises the most divergent forms. In this case, the livery becomes the stamp of a fauna,
INTRODUCTION. XVii
DIVERSE OBSERVATIONS CONCERNING THE
STUDY OF HYMENOPTERA IN GENERAL AND THAT OF THE VESPID& IN PARTICULAR.
Observations relative to the Synonymy.
Ist. [ make it a rule always to respect the most ancient name; however, if it is wrongly constructed and if it can be rectified without inconvenience, I do not seruple to correct it. Thus I spell Rhynchium instead of Rhygchium Latr.—Odynerus Bus- tellost instead of O. Bustellos Sauss., ete.
2d. When two different names have been affixed at the same date to the same species, I prefer that of the two which has been employed by the next subsequent author.
ad. I add the name of the author of a species only to tts specific mame. Consequently when the genus changes, I nevertheless maintain for the species the name of the author who first named it. Thus, I write: Odynerus 4-dens Lin., although Linnzus has described this species under the name Vespa 4-dens.
Montezumia Leprieurw Spin., although Spinola has described the species under the name of Odynerus Leprieurit.
Otherwise no author’s name would long keep its ground; besides those who act differently do so in order to substitute their own names for that of the primitive describer. Such a proceeding cannot be too strongly censured.
Let it not be said that there are drawbacks to the advantages of that nomenclature, for if it be desirable to know the complete name as given by the first author, it will be found, such as it is, in the synonymy.
4th. I admit neither collection names, nor manuscript names, nor ¢ dedéeris names, I admit for author’s name only the name
“of him who has first described the species or genus.
Any other manner of acting becomes the source of profitless research and of waste of time. Whoever is anxious to aflix his and is very important. In the succession of species it is generally observed that the colors vary much, even when the forms remain fixed (or vary
less); but there are other cases in which it is color that remains stationary whilst the forms vary. B
XVill INTRODUCTION.
name to a species that another has the task of describing, may for this purpose publish previously a short diagnosis under his name in any journal.
Observation relative to the Types in Description.
In insects in general, the female represents the type of the species. Though, in exceptional cases, the male may be the larger, the more beautiful, and at times with unusual appendages, he remains always more variable than the female. Among the Hymenoptera, the males have hardly any other part to play than a passive one; the other sex it is, which alone develops that remarkable activity which manifests itself in the interesting habits of these insects. The females are larger and more stable in their forms and colors. The slightest examination renders it apparent that it is among the females the type of the species is to be sought for, and by no means among the males. In the Vespide, especially among the Solitary Wasps, the males are small and variable; at times, one would be inclined to con- sider them as abortions; they do not offer as good differential characteristics as the females, and they are to be determined only by the tentative method in referring them ‘de visu” to their Tespective females.
There exists a number of species of which the males resemble each other so far as not to be distinguishable. This may be seen, for instance, among certain Odynerus, but it is especially among the Scor1a that this phenomenon appears in all its intensity. There is a whole category of species in the genus Zlis of which the females offer differences the most extreme, but of which the males are so confounded that they cannot be distinguished from each other. What is most remarkable on this score is, that these species are to be found spread over every continent, and that each continent numbers several of them. Thus:—
America: lis plumipes, limosa, trifasciata, dorsata, ete.
Africa: Elis collaris, capensis, elegans, africana, fascia- tella, ete.
Asia? Elis thoracica, annulata, marginella, limbata.
Australia: Elis radula, Z-cincta, etc.
Europe: iis villosa.
INTRODUCTION. xix
Some of these species may doubtless be distinguished by their size (27. villosa), or by the examination of their wings (ZH. Z- cincta); but in most cases, if it is not known where they come from, there is no possibility of determining them, not even of referring by sight to their females.
The same fact may be noticed in a very developed state among other species of Klis which present another system of coloring, and which forms a part of the subgenus Triznis. Thus the
Elis interrupta (Kurope)—texensis (Texas)—Xantiana (Cali- fornia),
though offering females very different from each other, coincide in the males.
I do not pretend to affirm, however, that all these males are perfectly identical. I only mean that they are so close neighbors that I have not succeeded in finding between them differential characteristics which appear to distinguish them.
The preceding will suffice to show that the femaie ought, at all events, to be taken as type of the species.
Preparation.
In a great many collections, it is usual to spread the wings and legs of the hymenoptera. This is mere amateur’s work, of no utility for study, sometimes even quite opposed to the purpose in view, by dissimulating the character of the insects instead of exposing it to view. ‘This practice is to be regretted, moreover, by its increasing the value of the insects, on account of the time and expense wasted thereby, so that one is loath afterwards to place them in the softener when it becomes necessary to dissect the mouth.
It is usual with me to prepare each of my insects only when about to study them, because by so doing I can, after having softened them, give them whatever arrangement may be best cal- culated for bringing into relief such special characteristics as are particularly useful in the group to which it belongs. As the use- ful characteristics are not the same in each group, the preparation ought to vary according to the species. Of the Hpipona % the mandibles are to be opened, the legs to be stretched downwards, so that it may be possible to examine distinctly the haunches and thighs; of the Odynerus $, approximate to the group of Q.
XxX INTRODUCTION.
nasidens, the antenne are to be lengthened out, in order to judge of their terminations, ete.
For almost all the Solitary Wasps, but particularly for the Odynerus, it is essentially necessary to be able to distinguish clearly the characteristics of the metathorax. Now this cannot be effected otherwise than by separating the wings in @ trans- verse direction or rather downward, and by bending the abdomen downward as far as possible, the basis of which will, by this means, become at the same time easy to study. This posture is, evidently, very different from that given to the insects by spread- ing them out. I can affirm, that, whenever one has neglected to give the insect this posture, the metathorax and the abdomen present themselves under the most delusive aspect, and may give rise to the most serious misconceptions. As to describing an Odynerus properly without having taken this precaution, it is an impossibility. One may, if need be, bend downwards the abdo- men without softening the insect; but then, if the wings are directed backwards, even obliquely, they are enough in the way to produce delusive appearances when the magnifying glass is used.
These observations, true especially for the Odynerus, apply likewise to all the sessile ventrated or semi-pedicellated Vespide.
On the Determination of insects.
There are two manners of proceeding, for the determination of insects. One is analytical, the other synthetical, the former employed by amateurs, the latter by naturalists. The first method consists, when having taken an individual insect, in turning over the leaves of a book in search of the name of the species till one supposes to have hit on the description. This method seldom leads to certainty, often to error.
The second method requires a collection as numerous as possi- ble in individuals. To procure it, the entomologist ought before all things to devote his efforts to a persevering and active chase after specimens. The greater the number of the representatives of each species, the more certain the determination will become. In difficult performances, we must always begin with the more easy and proceed from the simple to the complex. We must, there- fore, start by separating the most salient and most easy genera to
INTRODUCTION. xxi
study them first. Afterwards we must continue by way of climi- nation. As it is for the difficult genera, that it is especially important to adopt a good method, let us choose, for instance, the genus Odynerus and its approximates; it surely will answer our purpose thoroughly. Let us suppose that the pedunculiventrated genera have already been separated and that we have remaining only the sessiliventrated, say the genera Alastor, Monobia, Plero- chylus, Odynerus. 3
First we will exclude the Alastor, by the process of viewing of the wings. Scarcely any other will remain than the Odynerus and the Monobia; their species will at first appearance strike one as an inextricable jumble.
For the moment, we will not trouble ourselves about the Monobia, which are rare and southerly species. We will, there- fore, begin by confining ourselves to setting aside the Ancistro- cerus and the Symmorphus, characterized by the suture of the first abdominal segment, and we can then enter directly on the study of the species. But even here we will advance as far as possible without the assistance of books.
The next operation consists in sorting out the males and females in order to occupy ourselves exclusively with the latter. With a little practice this separation proceeds rapidly, since the males of the northern regions are distinguishable mostly by their entirely yellow clypeus. For whatever may concern the excep- tions (either from the females offering the same character, or from the males not offering it) one has still as object of consultation, the form of the antenne, organs which in most males are more generally terminated by a hook or a spiral. At last, as a final resource, and as an infallible means, we remove all doubts by counting the number of abdominal segments. The % have only 1, the 2 only 6.
We will first occupy ourselves only with the ? and will group the individuals by species on small boards. This is a work of time and patience. ‘l’o succeed, we will make use of every appreciable characteristic, even of the most empirical ones. In sorting out in this manner, the colors are always of the greatest assistance because they are obvious to the eye. One must, as much as possible, subordinate the importance of the spots to ¢ graduated order, in beginning with the most fixed and character-
xxii INTRODUCTION.
istic, as for instance the spots on the scutellum and of the post- scutellum. Thus :—
Range together all the species with post-scutellum alone yellow. : és “ és ‘“ scutellum alone spotted yel- low.
scutellum and post-scutellum both spotted, ete.
ce / se te c “ce
Then come the anterior and posterior borders of the prothorax; then the stripes of the abdomen, the spots of the metathorax, ete.
Thus you come to form more species than are really existing, every variety becoming a species; but, no matter, the work of reducing will at last arrive and will be easily carried through when species shall have been studied and known, as it were, by heart.
Then we may look into books and try to determine each species’ while having, beneath one’s eyes, the ensemble of individuals.
Here we can get on only by groping about a long time in uncertainty. Often after comparing these similar individuals we shall detect two species which at first had been confounded.
The determination can be carried on by two inverse proceed- ings. After having sorted out apart by one’s own observations the greater number of species, the entomologist often knows them already sufficiently to guess to what species such and such a description belongs. He can, therefore, either start from a species and seek the description which suits it, or start from a description, and in passing in review his series seek to what species this de- scription is adapted. Moreover, these two manners of proceeding verge into each other repeatedly, when one has beneath one’s eyes, a large ensemble of well-separated species. Indeed, when making use of the first proceeding, one often falls into the second, for one is often struck with the description of such and such a salient character which one recollects having observed in a species. Thus the search after one species leads to the determination of another. The work hastens along with accelerated motion and leads to results the more certain as each species is represented by a larger number of individuals comprising most of the possible
1 For this purpose short descriptions, i. e., diagnoses, which may at once be committed to memory, are very useful.
INTRODUCTION. XXill
varieties. In this entirely empirical labor, any process, even expedients are allowable.
Nevertheless, when one gets to the groups, in which the species lie close together, one is often puzzled, and there remains no way of exclusion.
Once the females determined, proceed to an analogous: sorting out and grouping of the males by species. Attribute to each female species its respective male, beginning by the more easy and proceeding always by way of exclusion. ‘This is a tentative work, in which one succeeds satisfactorily only when familiarized with a group which is being studied.
As to separating at the outset the Monobia from the Odynerus, the Symmorphus from the Ancistrocerus, the Odynerus from the Epipona, that cannot be done without being well acquainted with these groups so as to place therein at once the insects according to their facies. If one is not far enough advanced to do so, this separation will result quite naturally from the work of determi- nation; nevertheless, to distinguish the Jonobia, it will be neces- sary to dissect the mouth.
With that operation, we may finish, because we shall have no more to seek but among a small residue of species, whereas had we begun by establishing that distinction, we should have been obliged to dissect the mouths of all the Odynerus which have been excluded from this operation by the mere fact of their determina- tion. A work of determination made according to this manner of proceeding will afford synoptical views that alone will permit one to appreciate the true relations of species. Better than any other, it will prepare the entomologist to give comparative descriptions taken from a general point of view which will not lose itself in worthless details.
ee
ANALYTICAL TABLE.
Faminry VESPIDZ . : 6 ¢ ‘ : 4 5 : Tribe MASARINE . 3 6 A é : A é Gen. Trimeria Sauss. . , d ; Gen. Masaris Pub. 3 C 4 C Tribe OpYNERINZ . “ 5 ; : A ; I. The Anomalipennes . : ; ; ; . - F Gen. Gayella Spin. . : : : - : “ ‘ II. The Normalipeunes . : anata Legion I. The Zethites . 7 ° - ° Gen. Zethus abr... : : F 3 Division Zethus (sensu strictiore) . : Division Heros : C Division Zethusculus 5 , 4
A. Antenne of the males terminated by a rolling-up spiral 6 : : ° . . . a. Petiole presenting a nodulous or ovoid expansion b. Swelling of the petiole cylindrical * Metathorax not excavated . : . ** Metathorax excavated; the excavation mar- gined with sharp carine { Thorax short, quadrate or rounded tt Thorax elongate, attenuated anteriorly, ellip- tical . : ° : : : : B. Antenne of the males terminated by a hook .
a. Species having the appearance of the true Zefhus. Head more wide than high; thorax short, not being one anda half times longer than wide; dilatation of the petiole elliptical or cylindrical, a little contracted behind ; the second segment of the abdomen in form of a globular bell
RB. Species which have more the appearance of Fu- menes or Discelius. Head less inflated, less hol- lowed out at the occiput; thorax of moderate length ; petiole more as in the Humenes of Divi- sion « .
( xxv )
29
39
Xxvi
ANALYTICAL TABLE.
y- Petiole quite linear, filiform, depressed, very much elongate, as in Humenes of Division @. Facies
of a Calligaster . : . ° . C. Species which I do not know, an of which the antenne (% ) have not been described . : Division Didymogastra Perty d : °
A. Antenne of the males terminated by a rolled spiel B. Antenne of % terminated by a hook .
C. Species of which the section remains undetermined
Gen. Labus Sauss. : : : ‘ , : 3 Gen. Disecelius Lair. . : : ; : 4 : -
Legion II. The Odynerites . : ° : . ° : Gen. Eumenes Fabr. . -
Division Pachymenes . : - , ; 1. Form rather lengthened; thorax longer than wide; abdomen hardly depressed, the 2d segment not campanular : . . ° . .
A. Petiole campanular, Eriniant above beyond the middle, humped, the boss divided by a groove;
its extremity bordered by a salient band
a. Thorax rather compressed, lengthéned .
6. Thorax not compressed, moderately wide . B. Petiole pyriform, depressed, less inflated above, not divided by a groove . ° . . :
Division Omicron . : : . ° :
A. Thorax quite short, ae globular, larger:than the pear of the abdomen; the 2d segment of this wider than long (asin genus Tatua), wide-globular
B. Thorax a little more long than wide. The 2d seg- ment of abdomen sometimes rather elongate
C. Thorax not so wide; longer than broad; not larger, or even smaller than the pear of the abdomen. (Form very much as in Division Alpha.) . :
Division Beta . ‘ . : ; : :
a. Mandibles short, pointed in si males; “| rounded at tip, with separated small teeth in the females : . : ° . : . °
b. Mandibles more elongate, not truncate, rather hooked at tip, with strong teeth on the interior margin .
Division Alpha (Eumenes proprie dicti) . : : : A. Large species, with black wings. The pear of the abdomen rather depressed . ‘ 7 - :
B. Smaller species, with the abdomen more globular or compressed. (Regular type of Division Alpha)
PAGE
42
43 45 45 50 51 56 58 59 59 60
61
61
62
63
66
68
69
75
§3
88
88
96 92
93
95
ANALYTICAL TABLE. XXxVil
a. Wings smoky, with violet iridescence ° 5 b. Wings transparent or yellowish . , : ; * Second abdominal segment without lateral yel- low spots . . ; . . . °
** Second abdominal segment with a yellow spot on each side (sometimes wanting ip variety)
*** Second abdominal segment having on each side a yellow fascia, or a complete transverse
yellow band on its middle . ° c. Species of uncertain origin . : . : ; Division Zeta . 5 é ° 5 : . : Gen. Montezumia Sauss. . : ° C - ; :
Division Antezumia. Head flattened before. Abdomen pediculate. (Appearance nearly like some Pachy-
menes ) 3 “ ° : . ° . - Division Metazumia “ ; : - ° A : Division Montezumia (propr. dict.) - : - :
1. Abdomen pediculate é 6 : : .
2. First segment of the abdomen subsessile ‘ :
A. Thorax moderately lengthened, first abdominal segment funnel-shaped, convex, divided by a feeble groove. Vertex somewhat swollen
a. Wings transparent or ferruginous . : : b. Wings obscure, smoky, fuscous or black . - * Body more or less ferruginous : : °
** Body quite black . : : - . - B. Head strongly dilated on the vertex behind the eyes. Thorax much lengthened. First segment of the abdomen depressed or flattened above
and divided by a very distinct groove . .
Division Parazumia : : : é 3 Division Pseudozumia . : 3 : ° : - Gen. Monobia Sauss. . ; : : 7 : : A Division I 4 : : : ° : . . : A. Metathorax bispinose . : . < . . B. Metathorax rounded, unarmed 5 : . : Division II : : . : : : A -
A. Abdomen conical; the first segment wide and trun- cate. Hinder portion of the metathorax bordered by trenchant ridges and armed on each side with a dentiform angle , ¢ : : .
B. Abdomen ovalo-conical; the first segment more rounded, less truncate, less sessile. Metathorax rounded; its concavity not bordered above by trenchant ridges . , . ‘ ; .
—_ wy) ho
XXVlii ANALYTICAL TABLE.
a. On each side of metathorax a dentiform angle . b. Metathorax without distinct spiniform angles. C. Abdomen slightly fusiform, enlarging as far as the extremity of the 2d segment; the lst segment a little funnel-shaped, divided by a feeble longitu- dinal groove. Thorax lengthened .
Gen. Nortonia Sauss. . . . : . 2 : . Gen. Rhynchium Lair. “ . - : : : Gen. Odynerus Lair. . . : ° : , : : Definition of the subgenera. - ° ° ° ; Subgenus Symmorphus Wesm. . : : ; : ;
a. Segments 1-4 of the abdomen bordered with yellow b. Segments 1, 3, 4 of the abdomen bordered with yellow c. Segments 1, 2 only, of the abdomen bordered with
yellow . : : . Subgenus Ancistrocerus Wesm. . 7 : : ; Division Ancistrocerus (properly speaking) . . : Table to assist in the determination of the species of Ancistrocerus . : . . . = I. Metathorax having its concavity angulate, bondage all around by trenchant ridges. . A. Form lengthened, slender - °
B. Form still lengthened, but less slender
C. Body more gathered, normal, but the thorax still sensibly longer than wide .
a. Metathorax destitute of strong spines . 5b. Metathorax having two strong spines . .
D. Form very stubbed. Thorax cubical, nearly
as long as wide. ; . : : II. The concavity of the metathorax for ms no distinct lateral angles . 2 : . ‘
A. Posterior face of metathorax remaining mar- gined, but without distinct angles. Body slender, elongate . ° . . :
a. Post-scutel strongly truncate : - . b. Post-scutel not truncate, angulate posteriorly
B. Metathorax not distinctly marginate. Body
not slender, of normal form a. Abdomen nearly conical. The border of the 2d segment not reflexed. Body velutinous
PAGE 134 137
137 139 142 143 149 151 152 153
155
6. Abdomen more ovalo-conical; the border of ;
2d segment rugose orreflexed . . ;
ANALYTICAL TABLE,
c. Abdomen not as sessile; its first segment distinctly narrower than the second, which
* ig in the shape of a hawk’s bell, with a reflexed margin. Metathorax not excavated
in the form of a wide cavity, but of a wide
channel . r : 2 - : z
Division Stenancistrocerus , , ; ; : Table to assist in the determination of the species of Division Stenancistrocerus 3 ‘ ;
1. Formlengthened. Metathorax prolonged norizon- tally behind the post-scutel, then truncate ver- tically, etc. C 2 é : : F ;
2. Form very slender. Metathorax not so distinctly
produced behind the post-scutel; its con-
cavity large, etc. . C C - ; :
A. First segment of the abdomen rather funnel-
shaped or bell-shaped, truncate anteriorly .
B. First segment of the abdomen in form of a pro-
longed bell, rather squarely-rounded, about
as wide as the second segment, not con-
tracted before . ° ° ° ° °
a. First segment sharply truncate anteriorly .
b. First abdominal segment more rounded ante- riorly, rather like a square bell
3. Form slender, but the abdomen: sometimes slender,
sometimes ovoid, especially among the %.
The first segment cupuliform, narrower than
the 2d, having the suture indistinct, often presenting a transverse fluting bordered by
two traces of sutures. Concavity of the metathorax generally small, its borders in- distinct . : : : : : :
a. Suture of the first abdominal segment rather strong; excavation of the metathorax some- what distinctly margined . . ‘ ;
b. Suture of the first abdominal segment not so , Strong. Excavation of metathorax having
its edges rounded, without precise limits .
Division Hypancistrocerus : : ; - ‘ Division Ancistroceroides : : ; . :
Subgenus Odynerus Zatr. (sensu strictiore) . : Division Hypodynerus . ‘ : ;
Table to assist in distinguishing the species of the Divi- sion Hypodynerus . . . . ° .
XXIxX
PAGE
188 189 191
192
206
XXX ANALYTICAL TABLE.
PAGE I. First segment of the abdomen bell-shaped, pyri- form, uniformly a little comb-shaped. Appear- ance of Montezumia : F : : . 218 II. First segment of the abdomen offering an ante- rior and a superior face separated by a sort of transverse ridge or swelling (the true Hypo- dynerus) : : : : : : s a A. Form lengthened; first abdominal segment small, nodiform or pedunculiform, very much narrower than the 2d; its anterior face in a lengthened triangle. : . ° - AD B. Form shorter, wider; first segment wide on its posterior border; its anterior face in the form of an equilateral triangle and a little
pedicellate; its superior face large . . 222 a. Wings rufous along the anterior band . - 222 b. Wings fuscous, with violet iridescence . 224
C. Form very wide, short and depressed, first seg- “ment very wide; its anterior face sessile, in the form of a wide triangle; its superior face _ very short, 3-4 times as wide as long - 225 D. Form also quite chubby, but not so much depressed ; metathorax rounded, flat or con- vex behind, smooth, without marginal edges; first segment of the abdomen very short; its superior face transverse-linear. (Appearance of a Vespa.) : : : : - ee Division Pachodynerus . ‘ : : : . 228 Table to assist in distinguishing the species of the Division Pachodynerus : - : : . 229 Ist Section.—Thorax cubical (at least among the males) or square, lengthened. Abdomen coni- cal; the first segment very large, as wide as as second . : : 230 A. All the segments except An first border with yellow ‘ ’ ‘ : ; < oe a. Metathorax forming a lateral angle on each side . . ; : : ; : .. aon 6. Metathorax rounded, not forming on each side ;
a dentiform angle . - 3 236
B. All the abdominal segments aaaiiaed with yel- low orrufous . ‘ ; q ; . 237 a. Superior edges of metathorax not sharp . ST
6. Superior edges of metathorax sharp. . 238
ANALYTICAL TABLE,
C. Only the first two abdominal segments margined with yellow. (The 3d and 4th sometimes indistinctly marginate. ) ‘ ° ‘
2d Section.—Form more lengthened; thorax length- ened square or retracted behind. Abdomen less conic, more cylindrical or depressed ,
a. All the segments of the abdomen, except the
first, bordered with yellow :
b. Abdomen varied with black and rufous
Division Odynerus . ; : , ° - é C
Table to assist in distinguishing the Division Odynerus and Stenodynerus, with regard to Pachodynerus
Table to assist the determination of the species of Divi-
sion Odynerus . : : : : :
Section I.—Post-scutel sharply ikniiates its trans-
verse edge often crenulate. Abdomen conical
or ovate-conical; the second segment not
strangulated at base; the first segment in-
cluding it very naturally . . ° °
1. Posterior plate of metathorax angulate, forming
on each side a lateral dentiform angle-
A. Concavity of the metathorax polygonal, mar- gined with straight or arcuate ridges, which form at their meeting a sharp angle. The superior lateral edges superiorly ter- minating in a tooth or eminence, sepa- rated from the post-scutel by a deep fissure, or by anotch . ° eee ae
a. Ridges of the metathorax very salient; its posterior face excavated
* Posterior margin of 2d and 3d apaapntial segments reflexed : ° :
** Posterior margin of 2d and 3d mbar segments not reflexed, but impressed and rough . s : = -
6. The hinder face of metathorax more flat- tened; its superior edges not so salient
* The superior ridges forming two elevated spines behind the post-secutel
** The superior edges of metathorax very slight, only forming behind the post- scutel two very small teeth ‘ .
KXKI
PAGE
240
252
252
XXXll ANALYTICAL TABLE.
B. Metathorax as in Section A, but the superior edges of its hinder plate not so much elevated, no longer forming, in the females, distinct teeth behind the post- scutel, etc. “
a. Metathorax excavated ; one straight
b. Metathorax more flattened; the superior edges roughened, not acute
C. Hinder plate of metathorax no longer mar-
gined superiorly by sharp edges; lateral angles still existing . ° ° : : 2. Posterior plate of metathorax orbicular or more or less rounded, not forming on each side a distinct dentiform angle. . . :
A. Posterior plate of metathorax still margined with sharp edges, salient in its superior part, and forming on each side at the summit a tooth or elevation, separated from the post-scutel by a fissure (some- times very small). : 5 5
a. The concavity deep, excavated, with sali- ent ridges. Abdomen conical; its base sharply truncate . - . .
6. Posterior plate of metathorax less exca- vated; its marginal edges but slightly salient, although still sharp. Abdomen ovate-conical, slightly attenuated at base
B. Posterior plate of metathorax no longer mar- gined with sharp ridges, and not forming post-scutellar teeth = : :
a. Posterior plate of metathorax much exca- vated, margined with salient, blunt, and rough edges . . 5 5 °
b. Posterior plate of wietathorae more flat- tened; its margins rounded and pune- tured. : ; . ° é
Section II.—Body yet stubbed, not slender, nor jie drical. Abdomen not conical, but still ses- sile; the lst segment smaller than the 2d, as strongly or more strongly punctured than the 2d; the 2d constricted at base to fit into the first and more or less deformed; having its margin very strongly canaliculate and reflexed, and more or less swelled before the channel . : : : : .
PAGE
265 265
281
281
281
285
290
290
292
ANALYTICAL TABLE. XXXlii
PAGE A. Metathorax not narrowed below, much exca- vated, with very sharp edges; post-scutel bituberculate; abdomen quite deformed . 297 B. Metathorax triangular, narrowed posteriorly, not so much excavated, with sharp supe- rior ridges. Post-scutel not crested. Second abdominal segment channelled and reflexed, scarcely swollen : ; ‘ ; « 299 Division Stenodynerus . F . p mau Table to assist in the deeariuinaltion of the Stenodynert 304 I. Metathorax having its posterior plate superiorly terminated by two erect teeth, or by au erect crest . : ° : : -. 3809 A. Metathorax not prolonged tewelia the post- scutel, but truncate at its apex, posteriorly excavated, angulate on each side; the supe- rior edges of the posterior plate terminating in two erect spines, which are separated from the post-scutel by deep fissures. é - 309 B. Metathorax truncate, excavated; superiorly margined by an arcuate ridge, rather crenu- late, separated on each side from post-scutel by a fissure . é ° ° ° - + oLG C. Form not very slender. Metathorax produced horizontally beyond the post-scutel; then vertically truncate; the post-scutel quite enveloped by it posteriorly, not reaching up to the edge of the posterior face of metathorax ; the posterior face of metathorax superiorly terminating in an erect crest, parted by a fissure. Vertex in 9 having two pilose tu- bercles . . . : . . ; a eee II. Metathorax not forming erect spines or crests behind the post-scutel. Its superior face not produced behind the post-seutel. This last not posteriorly truncate, but angular, Post- scutel generally yellow, scutel usually black 312 1. Body slender, cylindrical. Concavity of the metathorax wide, sometimes rather dis- tirctly limited. First abdominal segment bell-shaped, rather elongate,widely rounded anteriorly, sessile or subsessile. Thorax rather elongate, vaulted, subcylindrical . 312
XXXIV . ANALYTICAL TABLE.
PAGE A. Metathorax slightly prolonged under the post- scutel beyond it, being truncate before; its concavity margined with sharp edges, nearly angulate on each side Abdomen slender, cylindrical; first seg- ment as wide as the second. Body vel- - vety . : : . . . . B. Metathorax scarcely, or not distinctly pro-
oo part Co
duced under the post-scutel, beyond it . Abdomen elongate, cylindrical, with the lst segment as wide as the 2d, elongate; or .
ovoid-elongate with the lst segment a little narrower, rounded : 2 : solo
* The Ist and 2d abdominal segments each
adorned with two yellow spots, or fasciz beside their marginal fascia . 9513
** Only the second abdominal segment
adorned with two yellow spots which
are often wanting, principally in the
males : - : : : pred *** No free yellow spots on the first two abdominal segments : . mars 1
2. Form less cylindrical, not much elongated, the thorax often short, and wide anteriorly, contracted posteriorly. Metathorax more convex, rounded; its fossette generally small, but always distinct. Abdomen ovoid or irregular, the first segment narrower than the second, not truncate anteriorly, not as
sessile; second segment more swelled than in the preceding, short and convex, con- tracted at base to fit into the first . . doa A. Form rather stouter, abdomen rather wide in the middle, but yet attenuated before. The fossette of the posterior face of meta- thorax rounded, always distinct . - dad a. Thorax but slightly adorned with yellow; (sometimes quite black, with a yellow spot under the wing); post-scutel quite black or adorned with two yellow dots . 333 4. Anterior margin of prothorax adorned with yellow, but not the posterior margin ; the yellow fascia often bilobed or inter- rupted. Fossette of metathorax large, rather triangular, occupying nearly the whole width of the metathorax . . 3o34
ANALYTICAL TABLE. KEKV
* Sometimes there are two little free spots on the 2d abdominal segments
** No lateral yellow spot on the abdomen .
ce. Posterior margin of prothorax, and often
also the auterior margin bordered with yellow. (Insects often velvety.) .
d. Prothorax quite yellow above. Scutel and post-scutel yellow . ; ‘ :
3. Body elongate, slender ; the abdomen especial- ly, veryslender. Metathorax convex, having no longer a distinct excavation, but sooner parted by a large groove, which separates its two cheeks. Abdomen slender, spindle- shaped; the first segment elongate, funnel- shaped, sometimes subpedunculate - .
III. Metathorax not produced superiorly beyond the post-scutel, convex; its hinder face parted by a deep groove. Post-seutel truncate— having a sharp edge . : - : :
A. Metathorax quite unarmed superiorly . B. Metathorax armed superiorly with two tuber-
cles, sometimes very small : ; :
Subgenus Epiponus 5 : : : 2 ; : : Division Antepiponus . : 5 : : A
Division Epiponus . : : : : - -
Appendix to the genus Odynerus : - . . < :
Gen. Leptochilus Sauss. . : : : : <a :
Gen. Pterochilus Alug. 4 " : : : : -
Gen. Ctenochilus Sauss.. ‘ _ ; : : ; :
Gen. Alastor Lepel. St. Farg. . : : : , . - Gen. Smithia Sauss. . : : : . : : : Appendix : - : x ; - ° ‘ . :
Index . : : : : : ° . ° . : ‘
Explanation of Plates. ° 7 R . 2 ° : :
346
oy II ~i oS
(es)
Ww hk @
Co OO
Sh]
———E————
VESPIDE
OF
AMERICA.
Famity VESPIDA.
CHARACTERS.— W ings folded longitudinally when at rest. Prothorax extended backward as far as the origin of the wings.
Mouth. Mandibles variable. Lip quadrifid or quadrilobed, sometimes only bifid; labial palpi not having more than four articles; maxillary not more than six articles.
Antenne elbowed, forming either a lengthened or a sub- filiform club, composed of twelve articles in the females, and thirteen in the males.
Hyes emarginate (except Paragia).
Abdomen sessile (without apparent peels, or pedicellate, composed of seven segments in the males and of six in the females, and armed with a retractile sting.
Legs slender, without hairs.
Wings always presenting. two recurrent nervures and three or four cubital cells. Both sexes are always winged.
The Vespidz are easily recognized by their folded wings (when at rest). It is true, this character is not always very distinct, especially among the Masarinx and Raphiglossine, but in this case one identifies them with certainty: Lst, by their elbowed antenne; 2d, by their prothorax, which, instead of forming a knobbed or transverse collar, offers a distinct upper surface, pro- longed on each side as far as the wing scales;' 3d, also by their ! As among the Pompilide and Pepside, from which they are distin- guished especially by their elbowed antennx, prolonged into clubs, by their folded wings, ete.
I | (1)
2 HYMENOPTERA OF AMERICA. [PART I.
general appearance, which is much more easily detected than described. |
The habits of the Vespide are quite different; some being social, some solitary, liying by rapine, and some parasitic.
These three moral tendencies correspond to the special forms which characterize the groups, into which we have separated the following subfamilies :—
2
I. MAsarina, or Parasitic Wasps.—Wings having an indistinct duplica- tion. Antenne sometimes enlarged into a club, their last articles often soldered together. Prothorax generally convex before. Scutel superposed upon postscutel. Claws of tarsi generally unidentate; posterior and inter- niediate tibiz terminated by two articulate spines. Lip quadrifid or bifid.
Wings having but three cubital cells. Eyes slightly emarginate.
II. Eumentny#z or Opyneriy#,! or Solitary Wasps.—Wings having a more distinct duplication, always offering four cubital cells. Antenne subfili-
form, with the articles distinct. Lip lengthened, quadrifid. Claws of the tarsi unidentate. .
III. Vespinz, or Social Wasps.—Having the same characters as the Eumenine, but the claws of the tarsi not toothed; the wings always having a very distinct duplication; the lip short, quadrilobed.
The Masarine can easily be distinguished by the inner neura. tion of their wings, etc. ; but the solitary and social wasps pre- sent so few distinctive general characters, that they are always puzzling. It will hardly be deemed superfluous to give here a table of empirical characters which may assist in distinguishing them in every case. . |
1 In my “Etudes sur la Famille des Vespides’’ I have given to this tribe the name of Humeniens (Eumenine), after the oldest genus of the tribe. But as the genus Odynerus is much more importaut, and as the tribe Vespine is named after a sessile genus, I have thought best to adopt in preference that of Odyneriens (Odynerine) for the sake of conformity in the names o: both tribes.
VESPIDA. 3
Soli‘ary Wasps. (Odynerinz.) Social Wasps. (Vespine.)
Mandibles often long and sharp, or | Mandibles always short and obliquely
having lateral teeth. Wabial palpi truncate, with the teeth rather ter- with three or four articles. Maxil- minal. Labial palpi always with lary palpi with three, four, five or four articles. Maxillary palpi with six articles. five or six articles.
Eyes always extending to the base | Sometimes an open space between the of the mandibles. base of the mandibles and the eyes.
Thorax always wide and truncate | Thorax sometimes strongly contract- before. ed before.
The second abdominal segment al-|The second segment sometimes fun- ways the largest, widening like a nel-sheped. The third segment bell, and like a socket to those; in that case the largest and a sort following. of socket for those following.
Clypeus variable, emarginate, biden- | Clypeus often cordiform, terminated tate, truncate or rounded on its by an angle or sort of tooth or by inferior border; never terminated a rounded lobe. by a tooth.
Second cubital cell always narrowed | Second cubital cell sometimes
toward the radial. square.
The second recurrent nervure some- | The second cubital cell always re- times received by the third cubital cviving the two recurrent nervures. cell.
Tre MASARIN ~&.
(Parasitic Wasps.)
Among these insects one notices in the antenne a tendency to consolidation of the articles and to a rudimentary condition of the maxillary palpi, as in general among parasitic insects. The abdominal segments among some species are constricted at the base so that one cannot receive another within it.
The wings often fold with difficulty; they offer but three cubital ceils, and the two recurrent nervures always terminate upon the second.
The lip is at times quadrifid, and sometimes bifid. When bifid it is also extensile by virtue of a peculiar mechanism.'
We know as yet but two representative genera of this tribe in America—one of which forms a genus limited to this continent.
' See: Saussure, Etudes sur la Famille des Vespides, III, 23, ete.; and Annales des Sciences Naturelles, 1857, VIL.
4 HYMENOPTERA OF AMERICA. [PART I.
Gen. TRIMERIA Savss.!
Antenne clubbed, lengthened ; the last articles very indistinct. Lip not extensile, tongue shaped, bifid. Labial palpi composed of three articles; maxillary apparently of none. Mandibles tolerably sharp. Abdominal segments constricted at their base ;
not retractile.
1. T. americana Savss.
Erinnys americana Sauss. Ann. Soc. Ent. Fr. 3d ser. I, Bull. xx, 1853.— Trimeria americana Sauss. Vespides, III, 1854, 81, Pl. iv, fig. 2, 9.
Hab. Brazil.
Gen. MASARIS Fas.
Antenne of % long, of 2 short, composed of twelve articles, of which the five last are soldered into a single bare mass (leaving but cight articles apparent). Articles 4—7 long in the males, short in the females, and incompletely soldered; the terminal mass (8th article) forming an oval club in the male, variable among the females. Zip extensile; the tongue bifid, inclosed in a contractile sheath, in the form of a lamina, placed edgewise: labial palpi short.2 Jaws short; maxillary palpi rudimentary. Mandibles short, arcuate, bidentate. Clypeus notched like the are of a circle. Metathorax flattened behind (bispinose). Abdomen flattened beneath, the segments contracted at the base, the third and following not retractile into the second; the abdomen equally wide and rounded at tip in the 2; lengthened in the 4, attenuated toward the end, bifid at the anus, and seg-
ments 2~3 armed beneath with a salient process.
' T at first named this genus Hrinnys in commemoration of a discussion upon the antenne of Masaris which for a long tine occupied the Entomo- logical Society of France (see /oc. cit.); but finding this name already employed, I changed it to Trimeria, which seems scarcely better, as there are already two genera Trimera. Nevertheless I think it better to retain the new name, since it is not identical with the last.
2 See for the composition of the lip, Sauss. Vespides, III, 23, and Annales des Sciences Naturelles, 1857, VIL.
MASARIS. 5
This remarkable genus counts as yet but five representatives, of which two are African, the others were recently discovered in North America.
The American Masaris differs from the African by having the labial palpi much longer. The Ist joint long; the 2d very short, about one-third or one-fourth the length of the first; the 3d arcuated, a little shorter than the first, and ciliated at tip. The Ath is quite rudimeutal, soldered to the inner face of the extremity of the third. The tongue is quite extensile as in the African type. The maxillary palpi are also quite rudimental, only appa- rent as a little tubercle. The American Masaris are also distin- guished from the African by the antenne of the 2? which are more globularly clubbed, nearly as in Celonites. The males which I can only judge by the figure given, have also the terminal part more globular or at least less elongated than in JZ. vespi- Sornis.
1. Antenne of 2 clubbed, having 5 soldered terminal articles, slightly dilated, not forming a distinct knob; the first article very long. Labial palpi very short M. vespiformis Larr. (North Africa.)
2. Antenne of ? terminated by a knob, as well as those of %; the five last articles forming an oval dilated mass. Labial palpi moderate.
i. M. vespoides Cress.—Nigra, flavo variegata, abdominis segmentis late flavo-fasciatis; fasciis 2-5 utrinque nigro-maculatis; 6° segmento flavo-bimaculato; alis flavescentibus; scutello planato metanoto bis- pinoso; antennis % elongatis, articulo primo brevi, globoso, ultimis 5 in clavam ovalem glutinatis ; 9 brevibus, primo articulo tertio breviore, 3° elongato, 4°, 5° mediocribus, ultimis 5 in clavam subglobosam glutinatis; abdomine % apice fisso, segmentis 2-3 subtus processibus 2 instructis.
Masaris vespoides Cresson, Proc. Ent. Soc. Philad. II, 1863, 69, Pl. iv; Hil, 673. *. Total length, 9 lines; expanse of wings, 15$ lines. Q. Total length, 8 lines; expanse of wings, 14 lines.
Male.—Clypeus subquadrate, deeply emarginate, with the angles rounded; mandibles somewhat obtuse, with two indenta- tions near the apex. Antenne a little longer than the head and
6 HYMENOPTERA OF AMERICA. [PART 1.
thorax; Ist joint short and thick, 3d to 6th about equal, some- what flat; 7th shorter, the 5 apical joints soldered into a broad oval knob, slightly concave beneath; the sutures somewhat distinct beneath. Metathorax forming on each side a somewhat flattened square angle, armed with an acute spine. Anterior femora rather curved and tibie dilated; posterior tibiz armed . with two spurs, one of which is elongate and deeply bifid. Tarsal claws simple. Abdomen elongate, convex above, gradually narrowed posteriorly ; apical segment subquadrate, deeply emar- ginate at the apex, with two longitudinal caring, each bearing a small obtuse tubercle on the posterior third of the segment; 2d and 3d segments beneath with a bifid projection at their base ; that of the 3d very prominent and arined posteriorly with an acute spine.
Body black; clypeus, apex of the labrum, middle of the mandi- bles, a transverse dilated line between the antenne and the inner and outer orbit of the eyes above the antenne, yellow; antennz above, with the base of the first and second joints black; the apex of Ast, inner side of 2d, and the 4 following joints, yellow; the anical joints yelléwish, varied with fuscous, blackish beneath. Anterior margin of prothorax, a spot beneath the wings, wing scales and a spot above, apex of scutellum and angles of meta- thorax yellow. Legs yellow, at base black. Each segment of the abdomen above with a submarginal yellow indented band ; apical segment with a quadrilobed yellow spot. Wings stained with yellowish, nervures honey yellow about the base, fuseous toward the apex.
Female.—Form shorter. Clypeus widely and deeply emar- ginate, very coarsely punctured, roughly folded and reticulate at the top. Labrum carinated, elongated and rounded at tip. Forehead carinated transversely between the antenne. Head and thorax densely, metathorax finely punctured; scutellum polished. Mesothorax carinated. The thorax depressed; the angles of metathorax flattened and depressed, terminating in an acute spine. Abdomen finely punctured; the segments very little constricted at base. First joint of the anterior tarsi rather dilated. |
Black, with fulvous pubescence. Antenne fulvous; the Ist and 2d joints blackish, the Ist yellow at tip; the club obscure on the upper side, blackish at tip. Palpi, the middle of mandi-
MASARIS. 7
bles, borders of labrum at base, a transverse line at top of clypeus and orbits of the eyes behind and over the emargination, yellow. Anterior border of prothorax and sometimes also the posterior edge, tegule, a spot under the wings and the angles of the meta- thorax, yellow. All the abdominal segments bordered by a wide yellow band, the first beneath interrupted ;‘ the three follow- ing more or less emarginate in the middle, and with a black transverse spot on each side. Anal segment with two yellow macule. Feet yellow; black at base. Wings a little grayish, with basal and costal veins ferruginous. Madial cell having its ereater width in the middle of its length; 2d recurrent vein in- serted after the middle of the border of the 2d cubital cell.
The yellow ornaments of % vary much in form and extent; still more in ?, the bands being of very different width, emargina- tion, spots, ete. The bands are sometimes emarginated in midale, and even interrupted on each side by the emargination. Some- times the fascia at head and thorax are divided into several dots.
Var. a. Sides of clypeus and labrum not margined with yel- low; no spot on the mandibles; a yellow spot at top of clypeus.
b. No yellow spot beneath the wings, no spots on mesothorax.
ce. Metathorax with posterior angles slightly produced and tipped with yellow.
This insect differs from I. marginalis by its very rough clypeus, by the carina of the forehead, its depressed thorax, by the spines of metathorax, ete.
It has much resemblance to IL vespiformis; but the knob of the antennee of the % is shorter; the projections of the 2d and 3d ventral segments are also differently constructed, that on the 2d segment of the American species being less developed and bifid, while that of the 3d segment is strongly developed, bifid, and bearing an acute spine behind. The antenn of the ? are very different ; the Ist joint being shorter than in JZ vespiformis, and the apex more swollen, as in Celonites. The color and dis- tribution of the markings of 2 is also very different, JZ vespi- formis 2 having its ornaments rufous and much more developed. Nevertheless the two species are so closely allied, that it is im- possible to separate them generically.
Inhabits Rocky Mountains, Pike’s Peak. (Coll. Ent. Soe. Phila. )
8 HYMENOPTERA OF AMERICA. [PART 1.
This fine insect was discovered by W. J. Howard, and described by E. T. Cresson. Numerous individuals were taken by Ridings in Colorado Territory on a plant allied to Lobelia.
2. M. zomalis Cress.—Nigra, fusco-hirta; antennarum articulis 4, 5 brevibus; clypeo arcuatim emarginato; thorace parum depresso; scutello carinato ; metanoto utrinque canthum compressum longe spi- nosum efficiente; corpore valde sulfureo-variegato; abdomine fasciis completis 5; ano bimaculato; alis subferrugineis. 9.
M. zonalis Cresson, Proc. Ent. Soc. Philad. III, 1864, 674,2. 9. 4%. ?. Total length 15 mill.; wing 8-9 mm.
9. Clypeus notched in arc of circle, convex, finely punctured. Labrum triangular, rounded at tip, pubescent, with fulvous hairs. The whole insect very finely sculptured. Thorax but little depressed. Metathorax flattened behind, but not depressed ; the angles compressed into strong carine, armed on each side with a long spine, as in J. vespoides.
Black, with brown hairs. Antenne fulvous; scape black, with a yellow spot; 2d joint black; 3d yellow; those following very short; the club blackish above. Mandibles, a spot in the fore- head, the whole orbits, the hind margin of prothorax, and (partly or completely) the fore margin, a spot under the wing, tegule, post tegule, margin of scutellum and the angles of metathorax, sulphur-yellow. A complete and regular submarginal fascia on all the segments of the abdomen; beneath, only lines of macule ; 6th sezment above, with two yellow spots. Feet black at base, vellow from the knees to the end. Wings as in the preceding, with ferruginous veins; radial cell rather brown; Ist recurrent vein inserted nearly at the inner angle; the 2d about in the middle of the 2d cubital cell. |
Var. A yellow spot on the clypeus; 2 spots on the forehead ; antenne more black; a yellowish tip on the coxe. Fasciz of the abdomen a little emarginated ; the band of the 6th complete.
%. A larger subquadrate spot beneath the insertion of the antenne, and the clypeus and labrum pale yellowish-white. Clypeus shaped like that of WM. vespoides %, but more flattened and less deeply emarginate at tip; antenne rather longer than head and thorax, proportioned as in Vespoides $, except that the club is not at all flattened beneath ; the joints pale yellowish-
MASARIS. ; )
white above or rather exteriorly, the two basal joints more or less black above at base, the fourth, fifth, and sixth joints at tip beneath, and the whole of the remaining joints beneath, pale ful- vous; the club above at tip, more or less black; the five articu- lations of the club are closely soldered together, the sutures indistinct. Wings asin I. vespoides %. Legs shaped as in Vespoides %, except that the anterior tarsi are scarcely ciliated, and the basal joint of the posterior tarsi is scarcely as long as the four remaining joints together, shaped like that of Vespoides % ; shining black; all the segments except the terminal one, with a continuous pale lemon-yellow band; those on the five basal seg- ments more or less emarginate on each side anteriorly ; the band on the sixth seement generally entire; apical segment. black, polished, deeply bifid or forked at tip when viewed from above ; when viewed in profile the tip. is rather broad and obtusely emarginate, the lower process being the shortest and stoutest ; when viewed endwise the tip has a subtriangular shape, concave, more or less lemon-yellow, with the lower process rather deeply emarginate; venter flattened, shining black, most of the segments with a lateral yellowish spot; the second segment with a more or less developed fold anteriorly, obtusely emarginate on the middle; on the disk of the third segment a large, robust, well- developed process, obtuse at tip, but with a short, stout, subacute spine posteriorly, similar to that of Vespoides %, but less developed. Length 5 lines; expanse of wings 9 lines.
This species is nearly the miniature of Vespoides, but is never- theless a very true species.
The male differs from that of JZ vespotdesin several points of structure, viz., the club of the antenne is rounded and not flat- tened beneath, the basal joint of the posterior tarsi is scarcely as long, while in Vespoides % it is almost twice as long as the re- maining joints; the apical segment of the abdomen differs much from Vespoides %, in having no carine on the disk, and in the tip being much more deeply bifid, both above and beneath, and the projection on the third ventral segment more robust, and not compressed or emarginate at tip as in Vespoides %.
In the 9 the thorax is less depressed, but a little more than in marginalis. The yellow ornaments are more abundant; the abdominal fasciz entire.. The scutellum is carinated, while it is
10 HYMENOPTERA OF AMERICA. [PART I.
not in Vespoides; the fore part of the mesothorax is also carinated, but the hind part is depressed, while in Vespotdes it is rather elevated. The 4th and 5th joints of the antenne are quite short, while in Vespotdes the 4th is longer than broad.
Hab. Rocky Mountains, Colorado Territory.
Mr. Ridings discovered this species in August on a plant most likely to be of the genus Phacelia.
3S. M. margimalis Cress.—Nigra, tenuissime punctulata; thorace quadrato, haud depresso, angulis metanoti compressis, haud spinosis ; macula frontis, marginibus pronoti, tegularum abdominisque segmento- rum 1-5 margine luteo; tibiis et tarsis luteis. 9. M. marginalis Cresson, Proc. Ent. Soc. Philad. III, 1864, 677, 9.
9. The whole insect, including the head and clypeus very finely punctured, coriaceous. Thorax quadrate, a little longer than wide, not depressed asin M. vespozdes, very finely punctured, a little rougher along the anterior margin of mesothorax. Clypeus convex, not carinated, not so much emarginate as in Vespoides. Labrum triangular, with the tip truncate and rounded; its margin and pubescence fuscous. The angles of metathorax not depressed, but compressed, not spined. Pubescence black (or grayish, when not fresh). Palpi, tip of mandibles, a line along the orbits behind and on the upper part of the sinus in front, a transverse line or 2 spots at the insertion of the antenne, luteus. Antenne fulvous; the 1st joint and upper part of the club, blackish; the other joint rather obscure on the upper side. Border of anterior and posterior edge of prothorax (more or less), and outer half of teguiz, whitish. Abdominal segments 1-5 adorned above with a narrow whitish band, not quite marginal, sometimes interrupted; at least the first. Tibiz luteus, tarsi fulvous. Wings hyaline, with ferru- vinous veins; radial cell pear-shaped, narrowly produced at its inner extremity; both recurrent veins inserted before the middle of the 2d cubital cell.
Var. The bands of head and thorax replaced by mere dots; clypeus with a white line; a macula on the pleura beneath the wing; anal segment with 2 white dots; the 3d segment beneath with a row of white dots.
Differs from JL vespoides by the finer punctuation, not rough clypeus, not carinated labrum, by its forehead without carina, ete.
Hab. Rocky Mountains, Colorado Territory.
MASARIS. Bt This insect, like the preceding, was discovered by Mr. Ridings.
I have a specimen of each of the three species here described through Mr, Edw. Norton
Tre ODYNERIN TZ.’ « (Solitary Wasps.)
Nails of the tarsi unidentate. Clypeus never terminated by a tooth; mandibles long, prolonged in the form of a sharp beak, or truncate, trenchant or dentate ; lip lengthened, often very long, always quadrifid, its lateral lobes forming long prongs separated even to its base and articulate.
In general, each of the four divisions of the tongue has at its extremity an opaque horny point; but in some cases these points disappear, and the lobes become very long, linear and plumose (Synagris).
Antenne scarcely clubbed, lengthened, simple in the 9° ; ter- minated in the & by a hook, or twisted spirally at the extremity, or simple. Hyes strongly emarginate; thorax always wide before ; metathorax not prolonged.
The abdomen is quite variable, but the second segment is always the largest; those following are retractile, and can easily
be forced back into the second.
The solitary wasps have not the nabit of living in soviety, and it is this characteristic which establishes the principal difference between the Odynerine and Vespine; for those distinctions which are drawn from their organization are not of much consequence, and can be reduced to the difference of elaws, which in the soli- tary wasps are armed with one tooth, and are simple among the social. The solitary wasps have, in fact, more carnivorous in- stincts. Although nourishing themselves by sucking flowers, they attack very many larve, spiders or other animals, to provide food for their offspring. Their larve are carnivorous, although the per-
! See on page 2 and 3 the table to aid in distinguishing the Odynerine and Vespine.
12 HYMENOPTERA OF AMERICA. [PART I.
fect insects sustain themselves by sucking vegetation. The Ody- nerine establish their nests in holes in walls, in the hollow interior of the stems of certain plants, or in habitations which they con- struct in the open air, of clay or of some vegetable and gummy substances. The eggs deposited in these nests are abundantly provided with larve or insects stupefied and reduced to a state of living mummies by the effect of the poison of the mother. These animals so inclosed are incapable of defending themselves, but retain sufficient life to prevent decomposition, and serve for the support of the larve of the wasps. The nests, after having been provisioned, are carefully closed by the mother with clay, with just sufficient covering that the young insect can pierce it to escape when it has undergone its last transformation.
Certain species of Odynerine (Zethus) appear to manifest a tendency toward social habits; they form small agglomerations of nests which resemble a little the irregular nests of humble bees (Bombus), but grouped yet more confusedly. But there always prevails this difference between the cells formed by the social and those made by the solitary Hymenoptera that the first have a cylindrical inner space, while the second are rather ex- tended masses which are not in regular juxtaposition, so that they seem more like spheres and ellipsoids joined together, than cells constructed side by side on a general plan. In-other words, the solitary species never seek to form a comb, although they some- times form agglomerations of cells. The most part of them do not construct these rough cells one upon another, but disperse them into different positions. - ,
I. THE ANOMALIPENNES. The first recurrent nervure received by the second eubital cell; the second recurrent nervure received by the third cubital cell. I. Lip extremely lengthened, bent back under the sternum ; man- dibles truncated obliquely, having terminal teeth. Genera: Raphiglossa Saunp. —Silenog/ossa Sauss.
Not known to be represented in America.
II. Lip shorter; Mandibles moderately long, sharp.
GAYELLA—ZETHUS, ie
Gen. GAWELLA Sprivn
Mandibles forming a beak by their union; labial palpi com- posed of four articles; maxillary, of six. First segment of the
abdomen contracted in the form of a knob or an inflated disk.
1. Gayella eumenoides Spry.
Gayella eumenoides Spinou. Gay’s Fauna Chilena (Hist. fisica de Chile), Zool. VI, 1851, 333, 1, pl. ii, fig. 2.—Sauss. Vespides, I, 1852, 6, pl. viii, fig. 4,
Hab. Chili. Il. THE NORMALIPENNES.
The two recurrent nervures received by the second cubital cell.
Legion I. The Zethites.
Mandibles short, obliquely truncated at the extremity, with teeth placed on the oblique border of the truncation, and so rather terminal than lateral (vide Saussure, Vespides, I, pl. ii, 1c, 3c; pl. ili, lc, 8c); forming by their union an obtuse beak.
Gen. ZETHWS Farr.
Mandibles short, obliquely truncated, and in seneral armed with teeth placed on the oblique terminal border. Lip and jaws lengthened ; labial palpi composed of 3-4 not feathery articles; the maxillary, of 6. | " Head large, expanded, in general wider than the thorax, dis- coidal or wider than long, swelled behind the eyes and emarginate like an are of a circle on its posterior face. Antenne inserted in the middle of its height. Clypeus rounded or in a large Square, in general wider than long.
Thorax slightly contracted before, sharply truncated on its anterior extremity, so that there is a space in the form of a circle between the head and anterior border of the prothorax ; this last generally flanged, carrying a crest in form of a sharp
plate or edge.
14 HYMENOPTERA OF AMERICA. [PART I.
Abdomen pediculate; the first segment in the form of a petiole, linear at its base, next inflated, and finally more or less con- tracted at its extremity, which renders the inflation globular or elliptical. The second segment, in form of a rounded bell, is often pediculate.
Sexual differences.—The males have the clypeus transverse, qaadrate, broad. Their antenne are terminated either by a hook, or by a spiral... The females have the antenne simple and the clypeus discoidal, often convex or lozenge-shaped, transverse.
Insects American.
This genus is easily recognized by its peculiar face, its trans- verse clypeus, large head, and the singular form of its abdomen.?
Among the Zethus the mandibles are quite short, overlapping beneath the clypeus; their triturating edge is terminal, not lateral as among the Humenine.
The size of the head is such that the eyes dd not entirely eover the cheeks. The metathorax has such variable forms that it recalls what one sees in the Odynerus; one can always here distinguish two lateral ridges, which extend from the base of the wing to the insertion of the petiole, as in certain Odynerus (Hoplopus or E'pipone). ,
The petiole is quite variable. Its expansion produces a form sometimes globular, sometimes more lengthened. The 2d abdomi- nal segment, whether subsessile or long pediculate, has the form of a bell or compressed oval. It is dilated suddenly (globularly), or gradually (like a pear). Its posterior border always presents two distinct foliations, the inferior projecting remarkably. This
1 It is not possible to establish a definite limit between these two forms: for often, with the hook, there also commences a spiral. When the spiral is very distinct, the 13th article, in place of terminating in a point as when it forms a hook, is lengthened, curved and obtuse. (See Saussure, Vespi- des I, pl. ii, fig. 3, d.)
2 The Zethus were mostly confounded with the Eumenes up to the time when I reunited the species in one genus, of which the buceate characters and the general form are too distinct to admit of any confusion. But I could not entirely separate from the genus Humenes, some species which I had not seen, and of which, even as wasps, the descriptions were incom- - plete (Z. rufinoda Lep.; £. substricta HAup., etc.).
~
ZETHUS. 15
form of the two first segments recalls specially that of Icaria (Social Wasps).
In general with Zethus, above all among the small species, the head and thorax are cribrose with coarse punctures. These some- times extend upon the petiole, but commonly the metathorax is less punctured and the abdomen very smooth.
Most of these insects are colored black and yellow; but the yellow markings are often wanting, and the variations are very numerous.’
The genus Zethus is particularly interesting in view of its zoological affinities. In fact, here the head becomes large and excavated posteriorly, as in the Vespine; the mandibles are short as among them; and one remarks a certain relationship in the appearance or some resemblances which seem to establish an affinity with the Social Wasps ;? while in the construction of the parts of the thorax, one recognizes some traces of the forms of the Odynerine sessiliventres.
Zethus seems also to establish a lien between the Odynerine and the Social Wasps by their habits; for the Zethus, although certainly solitary insects, construct nests composed of irregular cells, few in number but agglomerated, which is probably a pre- liminary step in the series toward the construction of numerous serried and regular cells. (See Zethus Romandinus.)
Even with all the gradations of form which we observe in passing from one to another in this genus, we do not think that one can divide the Zethus into more genera. Even the Asiatic type Calligaster seems so intimately attached to Ze/hus that we ean scarcely keep it separated now that more numerous Asiatic Species are known.
In conclusion, the genus Zelhus is a very numerous American group, peculiarly abundant in the intertropical parts of this con- tinent. In the United States it is represented by but one known Species; while in Mexico we find a very great number, whieb seem to be but an indication of a very much greater number which must exist in the other parts of tropical America.
' From my ignorance of this fact, I regret having published in my Mono- graphie des Gnepes Solitaires, descriptions of a certain number of species of Zethus, the distinctions of which are founded especially on the distribu- tion of colors.
2 See below, the division Zethus.
16 HYMENOPTERA OF AMERICA. [PART I.
This circumstance promises to render the study of the species exclusively difficult.
Division ZETHUS! (sensu strictiore). (Sauss. Vespides I, 9, III, 115.)
Second abdominal segment subsessile ; expansion of the petiole globular, lengthened. Thorax moderately lengthened. Meta thorax convex, presenting two rounded convexities, separated by a groove. Antenne of the males terminated by a spiral. The 6th abdominal segment bearing underneath two lamellar appen- dages (copulative’?). Species large, having a feeble sculpture, but not polished and with a dull metallic color.
It is impossible not to be struck with the resemblance of these insects to the Synoeca. The same form of head, indented be- hind, the same dull metallic color, great size, pediculate abdomen, ° mandibles almost the same form, ete.
The representatives of these two genera inhabit also the same countries of America. There is, in their color and appearance, one of those analogies which we sometimes find impressed upon insects of the same regions of our globe,’ and this seems especi- ally one of those openings that modern zoology should carefully mark as suitable to cast some light on the relationship of species.
1. Z. coeruleopennis® Fase. Vespa caruleopennis FaBr. Ent. syst. Suppl. 263, 1798. Zethus ceruleopennis Fasr. S. P. 282, 1.—Larr. Gen. IV, 137; Encycl. pl. 393, fig. 12, 13.—Sauss. Vespides, I, 9,1: Revue Zool. X, 1858, 64. Zethus brasiliensis Sauss. Vespides I, 10,2, 9; III, 115, & (prob. variety of this species). Zethus magnus Sauss. Vespides I, 11, 4, pl. viii, fig. 5, 4.
Abdominis petiolo globoso-clavato, sulco tenuissime partito.
Hab. South America, Cayenne, Para, Brazil, Quito.
! T have separated from this division a certain number of small species, which have very much the same form of abdomen, but which, by their clypeus and the angular form of the metathorax, find a more natural place in the division Zethusculus. :
2 The Vespides of Chili present a yet more striking example of this. See below Hypodynerus.
3 The Vespa surinama Lixn. (Gmel. V, 2759, 23), is either this species or a Synoeca,
ZETHUS. an |
2. Z. recurvirostris Dr Grrr. Vespa mexicana Linn. 12, Kdit. 953, 6.—Oxtv. Encycl. Meth. Ins. VI, 673. Vespa recurvirostris De Geer. Mém. III, 579, pl. 29, fig. 4, 1773. Vespa cyanipennis Fasr. Ent. syst. Il, 277, 86,1793; Polistes cyani- pennis, S. P. 275, 30. Zethus cyanipennis Latrr. Genera, IV, 138.—Ericus. Faun. et Flor. Brit. Guiana, ILI, 590.—Sauss. Vespides, I, 12, 6; III, 116; Revue Zool. *X, 1858, 63. Eumenes eyanipennis Lar. Hist. Crust. et Ins. XII, 345. Zethus lugubris Perty, Delect. An. Artic. 144, pl. 27, fig. 4, 1830.—Sauss. Vespides, I, 11,5; Revue Zool. X, 1858, 63. Clypeo 9 lato, satis rotundato, truncato; petiolo ovato-clavato, nigro vel rufo.
Hab. Brazil. Does not seem to inhabit Mexico.
3. Z. Chalybeus Sauss. Zethus chalybxus Sauss. Vespides, I, 10, 3; Revue Zool. X, 1858, 63.
Clypeo 2 transverso, rhomboidali, utrinque acute angulato, apice trun- cato, bidentato.
Hab. Brazil.
4.2. Carbomarius Smiru. Zethus carbonarius Surry, Cat. Brit. Mus. Vespid. 10, 5.
Hab. Brazil, River Amazon.
Division HEROS. (Sauss. Vespides, III, 115.)
Clypeus lozenge-shaped, transverse, forming on each side a sharp lateral angle; abdomen depressed, its second segment sub- sessile, enlarging gradually. Head swollen at vertex, and con- vex. Ocelli arranged upon a very oblique, almost vertical plane.
5. Ze SISAS SPIN.
Zethus gigas Srivoza, Ann. Soc. Ent. Fr. X, 1841, 129, 80.—Savss. Ves-
pides, I, 12, 7; Is. If, 115.
Calligaster heros Sauss.' Vespides, I, 23, 1, 2, pl. ix, fig. 6, 1852. 1 This name was given by De Haan; but it is a collective name, and after having cited Haan, for satisfaction, in the deseription of the species, we here suppress the name; considering that we do not recognize the col- lective naine, as we have said elsewhere, and do not wish, by setting an example, to preserve it.
2
18 HYMENOPTERA OF AMERICA. [PART I.
Hab. South America. Cayenne.
This type has very much the form of Zethusculus, on the part of its clypeus, and yet this form of clypeus appears in Z. spinipes.
Division ZETHUSCULUS Savuss. (Sauss. Vespides, I, 15; III, 118.)
Second abdominal segment subsessile, or briefly pediculate (the pedicle having at most a quarter the length of the segment). Petiole lengthened, its inflation variable.
Species small, ornamented with black and yellow.
The insects of this group often have the clypeus armed with two little separated teeth; this part is in general moderately rounded, but is at times lozenge-shaped, as in the division Heros, with the lateral angles sharp (Z. spinipes); the head and thorax are cribrose with great punctures, often rugose—the vertex offer- ing frequently a corrugation which includes the antenne. The thorax is generally short, and at times strongly angulate; the metathorax in particular is sometimes convex as with the true Zethus, and at times becomes angulate. The lateral ridges are very distinct and the flanks beneath are smooth, compared with the rest of the thorax. The posterior face of the metathorax is convex, having two convexities or moderately flattened eleva- tions, always velvety, Jess punctured than the rest of the thorax, and in general covered with striz or wrinkles, silky upon the dividing groove. Sometimes the posterior face of the metathorax is concave and offers under the post-scutel a little excavation, which recalls what one sees among certain Odynerinz. *One often perceives, aiso, two longitudinal carine which start from the. angles of the post-scutel.1_ When these carine become enlarged, they produce ridges which border the cavity (Z méniatus).
The petiole is quite variable; sometimes the knob is elliptical and depressed, but more often the swelling is moderately cylin- drical; at first somewhat large, it then diminishes in size gradu- ally to the extremity. In fine, it inclines to the campanular form, whether lengthened pyriform, or clubbed and calling to mind the Humenes or even tubular; but the other characters always suffice
1 When I say: metathorax bicarinate, it is meant that the carine exist on the posterior face of the metathorax; for as the /ateral edges or ridges are found on all the species, I do not mention them in the descriptions.
ZETHUS. 19
to enable one to distinguish these exceptional species from the Humenes (viz.: the clypeus transverse and not longitudinal, the mandibles truncate and not tapering, the head emarginate behind). The petiole is, in general, less strongly punctured than the thorax, more strongly than the abdomen.
Among the species of this division the antenne of the males are terminated, sometimes by a rolled-up spiral, sometimes by a hook. They form, in this way, two parallel series, based upon this character; in each one of them one sees the second abdominal segment at one time subsessile and at another becoming more and more pediculate. ‘These two series continue in the Didymogastra. The two forms of antennee combine with all the degrees of pro- longation of the abdomen, thus showing that the character drawn from the manner of termination of the antenne is not of any generic value.
As the most of the insects of this genus are not well described in my “Etudes sur la Famille des Vespides” I will here give a diagnosis of the species of Meridional America which I have before my eyes :—
A. Antenne of the males terminated by a rolling-up spiral.
a. Petiole presenting a nodulous or ovoid expansion.
G. Z. arietis Fasr.—Niger, capite et thorace valde cribratis. Clypeus cribratus, integer, apice subtruncatus. Pronotum vix carinato-margi- natum; metanotum minus rugosum, sericeum, in medio excavatum, striatum. Petioli tumor haud nodosus, elongatus ut in Z. Westwoodi at angustior, nitidus, tenuiter punctatus ; abdominis 2m segmentum paulum (sed distincte) petiolatum, elongatum, ovato-dilatatum (non globoso-dilatatum ut in Z. spinipede, Westwoodi, ete.). Petiolus et pedes rufi; ale infuscatew cyanee; % antennis subtus apicem versus fulvis. Longit 0.017.
Vespa arietis Fasr. Ent. Syst. Il, 1793, 282.—Oniv. Encyel. Meth. Ins. II, 676.
Polistes artetis Far. Syst. Piez. 280, 50.
Zethus arietis Sauss. Vespides, I, 14, 11; Revue Zool. X, 1858, 64.
Hab. Brazil.
?
%. @. rufinodus Larr. Eumenes rufinoda Larr. Genera, IV, 1809, 187, pl. xiv, fig. 5.—Sauss. Vespides, I, 42, 19. Zethus rufinodus Sauss. Vespides, III, 118, 4, pl. vi, fig. 3, 2.
20 HYMENOPTERA OF AMERICA, [ PART i.
May be a variety of the preceding.
Hab. Autilles.
§. Z. piriformis Sriv.—?. Ater, nitidus, punctatus, sed nihilominus politus ; clypeo et fronte planatis; illo apice subemarginato, margine punctato, de reliquo levi, substriato; pronoto valde cristato-marginato, sed haud bidentato, postscutello et metanoto velutinis, argenteo-sericeis, hoc parum striato, supra utringue levi; petiolo ovato-inflato, nitido, punctulato, margine flavo-limbato; secundi segmenti margine subja- cente producto; reliquis valde punctatis ; antennis subtus apicem versus ferruginescentibus; alis hyalinis, costa anguste nigra; cellula 2? cubitali trigonali. Longit 0.017.—Variat secundo segmento flavo-limbato. Zethus piriformis Spin. Ann. Soc. Ent. Fr. X, 1841, 135.—Sauss. Vespides,
Tedd, 2: Zeihus binodis Sauss. (per errorem) Vespides, I, pl. viii, fig. 8.
Hab. Cayenne.
This species is remarkable for its body appearing smooth, although punctured, having the punctures apparently effaced. I cannot say with certainty if this is really the species described by Spinola. The 2d segment of the abdomen is swelled suddenly, and globular, a.character which distinguishes this Zethus from Z. Sraternus.
9. Z. fratermus Savss.—Niger, punctatus; punctis 2 frontalibus fiavis. Pronotum paulum cristato-marginatum. Seutellum convexum, suleo partitum. Metanotum minus punctatum, sericeum, elunibus 2 convexis, sulco profundo sejunctis et utrinque carina verticali spatium striatum marginante instructis (non sunt ille carine laterales metanoti, sed faciei postice). Petiolus ovatus, sat brevis, punetatus, margine flavo; abdominis secundum segmentum distincte petiolatum, ovato-dila- tatum. Ale infuscate, costa nigra, apice et postice parum obscure.
©. Clypeus in dimidia parte inferiore flavus margine infero recto, dentibus 2 distaniibus nigris; antenne subtus, apicem versus flave. Longit 0.016.
Zethus fraternus Sauss. Vespides, I, 16, 14, 1852; Revue Zool. X, 1858, 163.
Hab. Brazil (lower provinces). Typus in museo Saussuriano.
The swelling of the petiole is a little flattened, and wider than in Z. piriformis; the second segment is more briefly pediculate, more gradually swelled and less globular. The body is more strongly punctured.
ZETUUS. 1) |
0. Z Westwoodi Savss.—Niger, capite et thorace grosse foraminato- cribratis, metanoto argenteo-sericeo; abdomine valde aureo-sericeo; petioli ampliatione ovata, elongata, haud clavata; secundo segmento petiolato; pronoti margine, macula subalari, scutellis, et abd. segmen- torum 1-2 margine, flavis; alis infuscatis; 9 clypeo integro utrinque margine flavo; % clypeo flavo, antennis subtus et cochlea fulvis. Zethus Westwoodi Sauss. Vespides, 1, 1852, 16, 15; ILI, pl. vi, fig. 2, 9.
Total length, 18 mm.; wing, 13 mm.
2. Clypeus polygonal, entire, covered with coarse punctures ; its inferior border a little truneated and rétroussé. Head and thorax covered with coarse cribriform punctures; on the forehead a feeble transverse depression, and above the insertion of each of the antenne a vertical medial depression extending to the clypeus. Prothorax angulate; its anterior border edged by a crest in form of a vertical lamina. Post-scutel unarmed. Metathorax rounded, smooth, hairy, with little or no punctuation, and covered with a silky down, in color strongly silvery or a little golden; its exca- vation has its upper edges moderately distinct; the lateral edges of the metathorax prominent. Petiole smooth, shining, golden, like the abdomen: the linear part almost naked, the expansion much lengthened, oval, occupying most of its length, a little swelled above. The remainder of the abdomen shining, distinctly golden, garnished with a silky pile, having cupreus reflections. Second segment ovate-globular, pediculate, the pedicle occupying a fifth of the length of the segment; the part swelled (or the bell), wider than long, but less wide than the length of segment; the second leaf of its border very prominent.
Insect black; on each side of the elypeus an oval spot, two dots above the insertion of the antenne, margin of the prothorax, a spot under the wing and scutels, yellow or orange. A border of this color occupies the margin of the two first segments; that of the first extending along the sides of the petiole (these mark- ings. are liable to be wanting, particularly on the head and the prothorax). The remainder of the abdomen and the second margin of the second segment, ferruginous. Antenne and legs black. Wings smoky, the anterior borders brown with a violet reflection. Wing scales yellow or brown.
The % as large as 2; clypeus yellow, slightly bidentate (a third hardly perceptible tooth between the two laterals). Fla- gellum of the antennz yellow beneath, especially under the
22 HYMENOPTERA OF AMERICA. [PART I.
terminal bend, which is sometimes entirely tawny. The yellow or tawny border of the prothorax is interrupted by some black points in both sexes.
Var. Size small, 13 mill. Prothorax black.
Ress. a. diff—Approaching to Z aztecus, but very distinet by the pedicle of the second segment being sensibly longer; by the petiole, of which the inflation is more lengthened, which does not form any prominence above and which is not strongly punc- tured.
Hab. The hot regions of the gulf side of Mexico. Tampico.
N. B.—The type from which I first described this species, J. L., has the “etiquette” Pefion de los Baiios, a locality of the valley of Mexico (cold region). This should be an error of the “etiquette,” for I have myself taken this species in the region approaching the hotter zone of Mexico.
Li. Z. Jurimei Savuss.—Gracilis, niger, nitidus ; capite et thorace tenni- ter punctatis (punctis quasi obliteratis) ; hoc nitido, metanoto brevi, albi- -dosericeo, planato. Petiolus ovatus, valde dilatatus et maxime depressus, nitidus, vix punctatus ; secundum abdom. segmentum basi petiolatum, dein globoso-dilatatum, ut petiolus nitidissimum; segmenta reliqua punctata. Pronoti margo, macula subalaris et tegularum limbus posti- cus, puncta 2 in scutello, macule 2 rotundate in metanoti parte imma, flava; abd. segmentorum limbus tenuissime albidus vel flavus. Ale infuscate.. Longit, 0.015 mm.
*,. Clypeus flavus, sericeus, superne niger, et margine tenuissime nigro, subbidentato; antenne subtus apicem versus fulve.
Q. Clypeus integer subtruncatus, niger, sublevis.
Zethus Jurinei Sauss. Vespides, I, 1852, 15,13; III, 118; Revue Zool. X, 1858, 162.
Hab. Antilles? South America. Caracas. (Typus in museo Genevensi et Saussuriano. )
12. Z. migricornis n. sp.—Nigerrimus, nitidus, punctulatus; meta- thorace et abdomine cinereo-sericeis ; abdominis petioli margine et linea submarginali angusta 2' segmenti, sulfureis; alis infumatis, costa nigra ; ? antennis et clypeo planato nigris, % clypeo albido, margine tenuiter nigro; antennarum flagello subtus albido-annulato; tibiis intermediis linea albidaornatis.
@ %. Total length 15 mill.; wing 10 mm.
The same form and sculpture as Z aztecus. Jet black, im- maculate, having only the yellow border of the petiole and a very
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ZETHUS. 23
fine submarginal sulphur-yellow line on the 2d segment. The antenne quite black.
%. Clypeus flattened, only delicately punctate-strigate, a little trilobed in the middle of its inferior margin; metathorax not so much hollowed posteriorly ; a little strigate on sides; the exca- vation not margined at top; the lateral carine very sharp and prolonged nearly down to the end, not obsolete beyond the angle ; the lateral faces polished. The swelling of the petiole not so oval, but more attenuated posteriorly; the second segment more pediculate, so that it might be almost classed in the Division Didymogasira.
The body is not clothed with golden silky hair, but only with a little grayish pubescence on the metathorax and abdomen; the face or clypeus not silvery as in Z. azlecus.
%. Antenne black; all the joints of the flagellum annulated beneath at their base with pale-yellow; the first joint having its macula near the end; the scape black. Clypeus broad, quad- rangular, transverse, whitish-yellow, not silvery; its inferior edge black, widely emarginate, with 2 distant teeth. ‘The intermediate tibiz ornamented before with a white line, running over tlie first joint of the tarsi.
Hab. Mexico, the eastern Cordillera. Orizaba (Mr. Sumi- chrast).
This species has the appearance of Z Jurinez, because of its oval petiole being posteriorly attenuated; and its black shining color, but it is smaller; its petiole is not impunctate, polished, ete.
b. Swelling of the petiole cylindrical.
* Metathorax not excavated.
1s. Z. Meydeni n. sp.—Niger, punctatus, tomento aureo ubique ves- titus ; pronoto cristato-marginato, sed angulis haud spinosis; petioli tumore cylindrico, subdepresso; corpore maxime fiavo-variegato; abdominis segmentis omnibus tenuiter flavo-limbatis ; pedibus flavis, femoribus nigro-variis ; alis pellucidis, venis ferrugineis.
*,. Mandibulis et clypeo flavis ; hoc in medio margine producto-truncato ; antennis fulvis sub seapo fascia flava, apice cochleatis.
Total length, 16 mm. ; wing, 11 mm.
2. Insect slender. Head wider than high, densely cribrose. Thorax densely cribrose; prothorax strongly flanged, but the
24 HYMENOPTERA OF AMERICA. [PART I.
angles not spiny; post-scutel feebly bilobate; metathorax con- vex, slightly divided by a simple furrow, strongly wrinkled—its lateral edges sharply carinate. Petiole of moderate length, its enlargement not being oval but in form of a tube slightly flat- tened, a little compressed behind, punctured; the remainder of the abdomen pear-shaped, the 2d segment bell-shaped, a little pediculate, slightly funnel-shaped, offering a second distinct border, not turned up at edge.
The whole insect of a shining black, everywhere garnished with a pile of tawny hair; a transverse spot on the forehead, sinus of the eyes, a spot behind each eye, a large border on the prothorax, a spot under the wing, wing scales, two spots on the scutellum, a band on the post-scutel, and two large spots on the posterior face of the metathorax, vellow. Segments of the abdomen all narrowly bordered with yellow; legs yellow, thighs varied with black. Wings transparent, nervures ferruginous.
%. Clypeus yellow, convex, terminated by a truncate projec- tion; mandibles yellow; antenne entirely orange or ferruginous, only a little dull above; the scape marked with a yellow line; the 3 last articles forming a rolled spiral.
Ress. a. diff.—This species is distinguished by the color of its antenne, and especially by the form of its petiole. This form resembles a little that of Z miniatus, but that has the angles of the prothorax dentiform and the petiole more cylindrie and coarsely cribrose.
The Z Heydent is much less coarsely cribrose than the Z. Aztecus, Westwoodi, or chrysopterus, which it slightly resembles ; and the exceptional form of the clypeus, %, also distinguishes it clearly: for with these species the clypeus is large, quadrate, the same as with the Z Jurinez, which is less punctured and has the wings obscure. The enlargement of the petiole is also very much more globular than among all these species.
Finally, this Zethus might be confounded with some one of | those species described by Smith, and which we cite at the end of the genus; but the author having omitted to indicate divisions into which these species enter, or the characters which permit one to classify them with precision, it is not possible to recognize them with certainty. The 7 curinatus presents much the same appearance, but it is very much smaller.
Hab. Brazil. (Museum of Senkenberg.)
ZETHUS. 25
This charming insect was communicated to me by Mr. de Heyden.
%* Metathorax excavated ; the excavation margined with sLarp caring.
| Thorax short, quadrate or rounded,
14. Z. Olmecus n. sp.—Niger, thorace crasse, metanoto crassissime foveolato-punctato; metanoto valde excavato, acutissime carinato ; petioli tumore cylindrico, rugosissimo, carinato; mandibulis, clypeo, punctis 2 frontalibus, 2 scutelli et 2 post-scutelli, margineque segmen- torum 1', 2‘, flavis; pronoto rufo-maculato; femoribus posticis subde- formibus.
Total length, 11 mill.; wing, 8 mm.
2. Smaller than most of the preceding. Head moderate, covered with scattered moderate punctures. Mandibles widened to beyond the middle; the cutting border oblique, having an acute point, a rounded tooth, and an obtuse lobe. No transverse carina above the antenne. The vertex having a little arcuate depression behind the ocelli. Thorax short; prothorax attenuated anteriorly ; its anterior border crested, the crest forming on each side a little acute but not marginal angle, the anterior margin being much narrower than the rest of the thorax; the lateral parts of. pronotum not margined. Scutel rather salient; post- scutel destitute of tubercles, quite truncate, having a posterior face, punctate along its superior arcuated margin. Metathorax quite angular in shape, as in some Odynerus ; its whole posterior face occupied by a large and deep sericeous excavation margined by very sharp and prominent carine, starting from the angles of the post-scutel; the top of the carine separated from the post- scutel by a fissure; the inferior extremity of the posterior carine meeting the lateral sharp carine, and forming with them a sharp angle; the upper side of metathorax divided into two triangles included between the carinew. The thorax covered with very large but not deep punctures; still larger on the metanotum, where they are nearly little grooves. Petiole having its swelling cylindrical, extremely coarsely punctured, the punctures very large and con- fluent; the middle somewhat carinated by the rough sculpture, the extremity a little contracted and with a large groove; on each side in the middle an obsolete sort of a tooth; the anterior extremity of the swelling truncate, polished. Second segment subsessile, convex beneath at base, but not tuberculous; tenuously
26 HYMENOPTERA OF AMERICA. [PART I.
punctured, but not more on its margin than elsewhere; the third segment densely punctate; the following impunctured ; the first margin of the 2d a little arcuate and depressed in the middle ; the second lamellar margin of 2d and 3d segment growing a little wider on the sides; that of the 3d rather transversely cut out in the middle third. Posterior tibiz arcuated, a little deformed.
Black, with a very dull silky reflection, rather fulvous. Mouth, mandibles, and clypeus, yellow, a little orange, or reddish at top of clypeus. Scape and the end of flagellum beneath, yellowish or tawny. ‘Two spots over the antenne, two lines on the vertex starting from the eyes, and two lines behind the eyes, not marginal, tawny. Both margins of prothorax and two spots on the lateral margins of scutellum, yeliowish-tawny ; two spots on the edges of post-scutel, the margin of petiole and a narrow yellow sub- marginal line on the second segment, yellow; anterior feet more or less ferruginous or yellow-tawny beneath. Wings subhyaline ; veins brown; 2d cubital cell lengthened at base (on the side looking to the base of the wing).
@. Clypeus rounded, densely and strongly punctured; a little velutinous ; its inferior margin arcuate, not truncate nor emargi- nate; its summit a little carinate. The head beneath and around the mouth, post-sternum and anterior coxe, sulphur-yellow.
%. Clypeus a little wider, having the same shape and color as in the 9. The oblique cutting border of mandibles with but 2 little notches. Antenne tawny beneath; the last two joints obtuse, forming nearly a hook. Anterior tibix, tarsi, and thighs beneath ferruginous; intermediate tibiz beneath and Ist, 2d, and 3d joints of the tarsi beneath yellow; the 3d segment slightly margined with yellow.
Var. Prothorax black, with its angles and two marks, tawny.
Hab. Mexico. The Oriental Cordillera. Orizaba (Mr. Sumi- chrast).
Ress. a. diff.—This is a very distinct species in the remarka- ble form of its metathorax and the rugosities of its petiole; quite different from all other Mexican Zethus, except from clypeatus. It differs by its more excavated metathorax, the excavation being polished and more carinated, and by its prothorax, more rounded anteriorly, not square shaped nor crested on the sides; by its rougher petiole, carinated in the middle, ete. It has such an extraordinary resemblance to Z. miniatus that it might be .
ZETHUS. 27
considered a Mexican variety of this; but it has the mandibles a little less indented, the petiole a little thicker and shorter; the lamella of 3d segment less cut out; and a less high coloration. It approaches in the same way toward Z. lobulatus. It differs from Z. toltecusby its short thorax, the carine of metathorax which converge on each side to a sharp angle, ete. Its appearance is that of a true Zethus. Hlab. Mexico. ‘The Oriental Cordillera, Orizaba (Mr. Sumi- chrast).
45. Z. minmiatus! Savss.—Parvulus, niger, caput et thorax mediocriter profunde punctata; pronotum cristato-marginatum, angulis spiniformi- bus ; mesonoti discus sulcis 2 profundis brevibus e scutello emergenti- bus notatus; post-scutellum angulatum, margine postico subconcavo, et in lateribus cristulis 2 (ut dentibus e seutelli angulis emissis) in- structum; metanotum ferrugineum mazime exrcavatum, utringue crista verticali e post-scutelli angulis emissa instructum ; petiolus cylindricus rugosissime cribratus; secundo segmento globoso-dilatato, subsessile. Caput fulvo sericeum, aurantiacum, fronte nigro; mandibulis et anten- nis aurantiacis; pronotum, macule subalares et scutellares, aurantiaca; abd. segmenta tenuissime flavo-limbata; ale secundum costam infus- cate ; pedes antici et intermedii aurantii. Longit, 0.011 mm.
Clypeus 9 discoidalis, 4 subtruncatus; in utroque sexu aurantiacus. Antenne % apice vix cochleate.
Zethus miniatus Sauss. Revue Zool. X, 1858, 64.
Hab. Para. (Typus in museo Saussuriano. )
16. Z. Lobulatus Savss. Zethus lobulatus Sauss. Vespides, II, 116, 2, pl. vi, fig. 4, 9, 1854.
Hab. Brazil. Amazon.
tt Thorax elongate, attenwated anteriorly, elliptical.
1%. Z. Voltecus n. sp.—Niger, cinereo-sericeus, punctulatus; thorace elongato, depresso, antice attenuato; metanoto crassissime foveolato- punctato, 4-carinato, foveold quadrata inter carinas instructo; petiolo cylindrico, rugosissimo ; 2° segmento subtus basi tubereulato; clypeo transverso, rotundato; antennis subtus, mandibulis, capite subtus, linea
1 Perhaps a variety of the following, with the second eubital cell less . retracted. In this the excavation of the border of the second segment was probably due to an accident of nature.
28 HYMENOPTERA OF AMERICA. [ PARY I.
post-oculari, punctis 2 pronoti et scutelli, margine abdominis segmen- torum 1°, 2°, coxis pedibusque anticis, flavis. 9.
Total length, 12 mm.; wing, 8} mm.
Head moderate, moderately punctured; the trenchant margin of mandibles very obsoletely lobed. Thorax elongate and depressed, polished, covered with delicate punctures, having a tendency to strie, but the pleur covered with stronger scattered punctures, much attenuated anteriorly and posteriorly ; its ante- rior margin short, margined; the disk of the mesothorax flattened, with two sulcose places at base; scutellum flattened, not divided by a Sulcose basin, post-scutellum very small; metathorax elongate, oblique, triangular, very coarsely punctured (or rather reticulate- rugose); its lateral caring very sharp, the sides under the carine polished, but a little reticulated near the carinz, posterior face having two strong carine, starting from the angles of the post- scutel, the extremities of which do not meet the lateral carine ; the space between the middle carinz forming a square excavation, rather widened posteriorly, polished, furnished with gray seri- ceous hair, as also the terminal acute angles of metathorax, behind the end of the middle carine.
Petiole (as in Olmecus) cylindrical, truncate and polished in front, extremely coarsely punctured, very rugose, a little carinated at base, the extremity marked with a semicircular groove, and also constricted on each side. Second segment of abdomen rather elongate, a little depressed, with quite delicate oblique punctures ; the punctures beneath stronger, on the base swelled tuberculously ; the first margin above slightly angular in the middle, the subjacent lamina very salient on the sides but very little in the middle; margin of the 38d segment arcuate, the lamellar edge strongly and broadly cut out in the middle.
Black, furnished with silvery hairs (except on the head, where they are yellowish); a line of them behind the eyes (but not marginal) and a line or the scape, yellow; the flagellum of 2 be- neath yellowish-ferruginous; two dots on the prothorax, two on the scutel, margin of petiole and a filiform line on the upper margin of the 2d segment, yellow; prosternum, anterior coxe, and legs, yellow; intermediate knees and tibiz annulated with yellowish- brown. Wings washed with brownish, with a golden reflection.
2. Clypeus in a rounded lozenge-shape, truncate at the top and ©
ZETHUS. 29
extremity, but without angles, delicately punctured-strigate. Clypeus, mandibles, and the under part of the head, yellow.
Ress. a. diff.—This species has just the same form of head and clypeus and just the same system of coloration as Z. olmecus ; the petiole is also the same, but the thorax, lengthened, flattened, very delicately punctured, the metathorax less excavated, with not so salient earine, make it easy to distinguish. ‘The middle earine of metathorax stop before reaching the lateral carine. The appearance of the insect is quite different, and it looks more like a Discelius (D. zonalis) than like a 4ethus; and this appearance, due to the elongate thorax, distinguishes it also from 4. niniatus and lobulatus.
Hab. Mexico. Oriental Cordillera (Mr. Sumichrast).
B. Antenne of the males terminated by a hook.
a. Species having the appearance of the true Zethus. Head wider than high; thorax short, not being one and a half times longer than wide; dilata- tion of the petiole elliptical or cylindrical, a little contracted behind ; the second segment of the abdomen in form of a globular bell.
18. Z. spimipes Say.—Medius, niger, nitidus, densissime et grosse cribrato-punctatus; punctis 2 frontalibus flavis; clypeo lato, 9 nigro, subbidentato, rugose cribrato; % punctato, albido, surpra nigro; antennis © atris, % linea in scapo albido; abdominis secundo segmento minus conspicue punctato, subpedunculato; petiolo inflato, campanulato, grosse punctato, apice flavo-marginato.—Variat 9 % pronoto, lateribus, scu- tellis, albido variegatis et abdominis secundo segmento margine albido.
Zethus spinipes Say, Bost. Journ. I, 1837, 387, 9.—Sauss. Vespides, III,
er iee| 10.
Humenes substricta Haup.! Proc. Acad. Phila. II, 1844, 54.—Sauss. Ves- pides, III, 152, 42.
Zethus variegatus' Sauss. Vespides, I, 13, 9, 09,1852; Revue Zool. X, 1858, 66.
Eumenes pensylvanica Hany. Proe. Acad. Phila. 1853, 365, 4%.
Zethus bicolor Sauss. Vespides, I, 17, 16, 4.
2. Insect of medium size; ocelli disposed in a wide triangle. Clypeus having the form of a transverse lozenge, twice as wide as long; having the lateral extremities very sharp, and its ante-
' The collection, with bad locality marks, of M. de Rom&nd, has led me into very many errors.
30 HYMENOPTERA OF AMERICA. [ PART I.
rior border armed with two little distant teeth. Head extremely dilated at the vertex, strongly excavated behind, wider than the thorax. Thorax very short, not being one and a half times longer than wide. Prothorax slightly retracted before, its ante- rior margin bordered by a sharp projection, which forms on each side an indistinct angle. Mesothorax carrying on its posterior part four longitudinal furrows, and upon its anterior part one middle groove. Scutellum divided by a sinus. Metathorax offering a feeble concavity, wrinkled and striate. Petiole moder- ately short, its expansion globular, having almost the same form as in the Z. cwruleipennis, but less contracted behind and trun- cate; the second segment globular-ovate, but depressed.
Insect black, polished and shining. The metathorax garnished with a grayish pile. Clypeus, head, thorax, and petiole densely cribrose with great punctures: this last carrying near its terminal border a large sunken place. Abdomen sown with finer punctures, sometimes very fine. ‘There is often a slight depression toward the middle of the border of the second segment. A frontal dot at the insertion of each of the antenne, the border of the prothorax or only two spots upon the shoulders, often a spot below the wing, a band or two spots upon the scutellum and the anterior border of the post-scutel, and also two spots at bottom of the metathorax, of a pale yellow. Margin of the petiole, and a narrow border along the margin of the second segment, of the same color. Feet black. Wings brown, with violet reflections.
%. Smaller. Clypeus wide, moderately rounded, not having a lozenge shape, its inferior border straight, hardly bituberculate. This part either wholly or only in its inferior moiety, whitish. The seape of the antenna before, is ornamented with a whitish mark; the terminal hook black; on the face is often a little yellow dot at the side of the insertion of each of the antenne. The third abdominal segment is often adorned with a whitish border. This is the Z. substricta Hald. The female presents the same variations.
Var. a. Scutels, prothorax, and two great spots on the meta- thorax yellow (Z. variegatus, bicolor).
b. Often the scutels have hardly any spots, and the second segment is scarcely edged with pale yellow (Z substrictus). Markings sometimes ferruginous. '
c. Certain specimens are entirely black, with a little yellow
ZETHUS. 31
about the end of the petiole. These are the Z. spinipes Say ( ), and the Humenes pensylvanica Hald. (% ).
d. Quite black; the clypeus margined with yellow (% ) (Mis- souri; Edw. Norton).
The punctures vary quite notably among this species. The head and the thorax are very coarsely cribrose; with the ?, the clypeus is strongly rugose; the vertex often becomes shining from use. Among the 9, the clypeus is less strongly cribrose. The second segment is sometimes hardly at all, sometimes quite strongly punctured. A specimen from Florida has the swelling of the petiole very coarsely cribrose.
Ress. a. diff.—Wasily recognizable by its size, which is superior to that of all the following species, and by its violet wings.
Hab. United States. Conn., Pa., Ill., Tenn., Ind., Fla. (14 &, 6%).
Nota.—As J have already said (loc. cit.), the description given by Say is very defective, and calls for an interpretation. When this author says: ‘‘Peduncle rather slender,” it is without com- parison with the other species, the most of which he did not know. The “piceous dentate band of the margin of the peduncle” is but the subjacent double margins, which do not make it dentate except in the color. The “posterior margin abruptly and smoothly impressed of the 2d segment,” alludes to the subjacent lamina on the border of the segment which are salient in almost all the insects of this genus, and which appear like a more dis- tinct border than the veritable margin of the segment, which has the yellow band. By “ tibiz spinous behind,” the author means without doubt the posterior extremity (which offers a very short border) armed with stylets common to all the Vespides. (From this the name spinipes.) Finally, the author says that the second segment “has a distinct neck at base,” which signifies a very short neck, for if it had been long, the word distinct was out of place. This species is not then a Didymogastra, but really a true Zethus (or Zethusculus), which makes us think, that it really is, without any doubt, the present species
19. Z. spimosus Sauss. (Fig. 2, 2a.)—Parvulus, niger; capite, tho- race et petiolo grosse percribratis ; clypeo integro, 2 nigro-sericeo, § flavo; fronte carina transversa et linea flava; pronoti margine crista- tissimo postscutelloque spinoso fascia flava; petiolo cylindrico, rugoso,
32 HYMENOPTERA OF AMERICA. [PART I.
flavo-marginato; segmentis tenuiter flavo-limbatis ; secundo sericeo, nitido, punctato; alis subhyalinis. Zethus spinosus Sauss. Revue Zool. IX, 1857, 270.
Total length, 13 mm.; wing, 9 mm.
2. Small, excessively rugose. Head large, dilated and con- vex, densely cribrose with great pits; face carrying a transverse ridge, which covers the insertion of the antenne. Clypeus almost transverse, convex, punctured, but much less rugose than the head; covered with a pile of dull gray silky hair; its inferior border entire; the middle of this border a little arched.. Thorax all cribrose with large sunken pits resembling a sieve. Its ante- rior border carrying a transverse rim in the form of a quite pro- minent lamina, which prolongs itself a little at the sides, descend- ing along the margin of the prothorax. Post-scutel armed in the middle with a spiniform sharp and raised tooth, or rather, with a spine. The concavity on the posterior truncated face of the metathorax is divided by a furrow. The metathorax is very angulate; its lateral ridges very sharp; its posterior concavity very distinct, striate, bordered by two parallel longitudinal ridges, beyond which the metathorax is again quite rugose. Petiole as rugose as the thorax; its base alone smooth; its expansion lengthened, cylindrical, but little contracted behind, and cribrose with very large confluent punctures. Seeond seg- ment globular-ovate, a little pediculate, its pediele hardly equal- ling a sixth the length of the segment. This segment is polished, shining and sericeous, although punctured, and appearing as wide as long when examined from above.
Insect black, with a transverse line on the face, a little dot behind each eye, margin of prothorax, post-scutel, two pyriform lines on the metathorax and a line on the border of segments 1, 2, 3, yellow. Sometimes also all the segments are bordered by a yellow or ferruginous band, and the last segments now and then ferruginous. Legs black; tarsi and tibie garnished with silky ferruginous hair; anterior knees spotted with yellow; interme- diate tibiz with a yellow line; the femora with a spot at end. Wing scales black, terminated behind by a yellow point by the side of which is a little yellow process. Wings sub-smoky, with brown nervures; the 2d cubital cell triangular, quite contracted anteriorly. |
ZETHUS. 33
%. Clypeus transverse quadrate, either wholly pale-yellow, or only its lower part; inferior margin entire and arcuate; the last two articles of the antenne tawny beneath.
Var. a. Two yellow spots on the scutellum.
b. The yellow mark of the frontal ridge and that on the post- scutel, interrupted; the face presenting but two yellow points. The border of the prothorax is sometimes sprinkled with black dots.
ce. The yellow markings hardly visible. Prothorax black. Legs black; wings a little smoky, with some ferruginous tints and the nervures brown.
d. The spine of post scutel yellow or black.
e. In small specimens, principally %, the spine is obliterated, or replaced by a little longitudinal carina.
jf. The peduncle of the 2d segment rather longer; the spine of post-scutel obliterate.
g. The extreme edge of the clypeus % black, or partly black, ‘which causes very fallacious appearances.
Ress. a. diff.—This species is very distinct, by its ridges, prominences, and rugosities, by the very large punctures of its petiole, and especially by the long spine of its post-scutel.
Hab. The gulf side of Mexico, in the warm parts. Tamaulipas, Huasteca, ete. Verycommonin Tampico. I have taken a score of specimens in view of the town of Pueblo-Viejo, against posts exposed to the sun. Various specimens also from Orizaba.
Fig. 2. The insect seen in profile, enlarged. 2, 6. Its natural size. Fig. 2, a. The abdomen more enlarged.
20. Z. imitator n. sp.—Niger, crasse, dense punctatus: metanoto Le) ? 1 minus erasse punctato; petiolo ovato-cylindrico, crassissime cribrato ; punctis 2 clypei; 2 frontis, pronoti margine, macula subalari, tegularum limbo, scutelli fascia interrupta, post-seutelli fascia, maculis 2 metanoti, , pta, p ,
abdominis segmentorum 10-39 limbo anguste, tibiisque intermediis basi extus, flavis. 9.
Total length, 12} mm.; wing, 9 mm.
2. Form and sculpture about the same as in spinosus. Head small. Clypeus much rougher, very coarsely and confluently punctured, not broad, but rounded, more prolonged and truneate. A earina between the antenne, prolonged on the elypeus. The rest of the punctuations about the same, very rough. Prothorax
3
34 HYMENOPTERA OF AMERICA. [PART I.
a little more elongate; its angles very prominent; the post- scutellum quite destitute of a spine. Metathorax triangular, not earinated and not so rough. Petiole a little less eylindrical,-a little more swollen, coarsely cribrate; the beginning of the swelling punctate like the rest, not polished (as if smelted) as in spinosus ; 2d segment less globular, more pyriform, only punctate along its margin.
The ornaments more numerous than in spinosus, having a spot on each side of the clypeus, two on the face, the scape beneath, the border of prothorax, a macula under the wing, edges of the tegule, an interrupted fascia on the scutel and on the post-scutel, two macule on the metathorax, margin of petiole and a submar- ginal line on the edge of the 2d and 3d segments, yellow. The rest of the abdomen brownish; an abbreviated yellow fascia on the intermediate tibiz. Wings hyaline, a little brownish along the anterior margin; the 2d cubital cell not anteriorly contracted, having a distinct radial border.
Ress. a. diff.—This species slightly resembles Montezume but is very distinct by the rest of its coloration, by its swollen, not depressed, and more coarsely cribrose petiole; and by the second, more globular, less elongate segment of the abdomen.
It differs from aztecus and Westwoodi by its more sessile 2d segment, its more coarsely cribrose and more cylindrical petiole, its maculated metathorax, without excavation, only parted by a suleosity ; smaller head, rough clypeus, ete.
It is nevertheless an embarrassing species, intermediate between spinosus and Montezume.
Hab. Mexico; the Oriental Cordillera (Mr. Sumichrast).
21. Z. clypearis n. sp.—Niger, crassissime dense cribrato-punctatus ; pronoto acute angulato; metanoto 4-carinato, post-seutelli angulis dentiformibus; petiolo ovato tumido; punctis 2 frontalibus, pronoti margine, punctis 2 scutelli et 2 post-scntelli margineque petioli, flavis ; margine 2' et 3" segmenti sinuato, — premarginali flava; alis fumosis. 4%.
.
Total length, 13 mm.; wing, 9 mm.
Form and punctures as in Z spinosus. The head very little wider than the thorax; the thorax short, crested in front, very square anteriorly ; its angles sharp, a sort of crest bordering the sides of pronotum up to the wing-scale. Scutel rather salient;
ZETHUS. oD
post-scutel truncate, somewhat emarginate ; its angles seen from before, elevated as two triangular tecth: Head and thorax quite densely cribrose with very coarse confluent punctures; the scutel divided by a flat line. Metathorax coarsely but not so deeply cribrose, short; its lateral edges very sharp; the posterior face having two strong vertical carine, starting from the angles of the post-scutel, but not going down to the extremity ; the channel between them punctate; the sides of thorax as cribrose as the dorsum, those of the metathorax not quite so rough. Petiole quite coarsely cribrose, rather bidentate, with the anterior side polished, impunctate (as if smelted) as in azlecus, but the swelling not cylindrical (as in aztecus) but oval, thick, and truncate as in olomitus. The 2d segment subsessile (its form being a half sphere), and punctured; its second lamellar edge wide, getting wider on the sides. The first border of the 3d segment advanced in the middle; the 2d lamellar border sinuate, advanced in the middle, and emarginate on each side; getting wider outside of the emargination. The other segments very delicately punctate.
Black; the pilosity brown; that of the abdomen long and ful- vous on the 2d and 8d segment. A line on the anterior margin of the mandibles, two spots over the antenne, anterior border of prothorax ; two dots on the angles of scutel, two on the post- scutel, posterior border of petiole, and submarginal border of 2d and 3d segments, yellow. The posterior margin of prothorax and the margin of the tegule, brown; the second border of 2d and ad segment piceous. Knees and tarsi brownish; a yellow macula at end of the Ist femora; a yellow line on the Ist and 2d tibize outside; this sometimes tawny. Wings clouded with brown, with yellowish reflection.
%. Clypeus rather rounded, black, very coarsely cribrose, its inferior margin with three indentations in the middle, two little earine terminating in the external teeth; its surface very convex, having a very prominent transverse swelling, somewhat like a very obtuse carina; a yellow triangle with the angle turned downwards extends from that swelling to the end, and terminates in the middle indentation of the inferior margin. Antenne rather thickened, terminated by a short biarticulate ferruginous obtuse hook.
Ress. a. dif/.—This very remarkable species comes quite near to Z. spinosus, from which it differs by its bidentate, not spined
36 HYMENOPTERA OF AMERICA. [PART I.
post-scutel and by its square, angled, not contracted prothorax ;
by its metathorax and petiole, ete. The very coarse punetation
and very particular details of form of all the parts of the body
distinguish this species from all the other Mexican Zethus, except
from Olmecus with which it must be compared. | Hab. Mexico. The Oriental Cordillera, Orizaba.
22. Z. Aztecus Sauss. (Fig. 1, 1e.)—Niger, rugose punctatus; pronoto antice valde cristato; fronte transversim in lineam elevato, flavo- bipunctato; petiolo ovato-inflato, crasse punctato; secundo secmento subpetiolato, fulvo-sericeo; pronoti margine, macula subalari, scutelli maculis 2, post-scutelli fascia abdominisque segmentorum 1-3 limbo, flavis; alis subhyalinis.
Zethus aztecus Sauss. Revue Zool. IX, 1857, 270.
Total length, 15 mm.; wing, 10 mm.
2. Head, thorax and petiole cribrose with coarse crowded punctures, but less rough than with Z. cristatus and Z. spinosus. Clypeus polished, cribrose with more distant oblique punctures, and hardly notched on its inferior border; the emargination divided by a little middle tooth; a little wavy transverse carina on the vertex, forming a sort of extension upon the insertion of the antennz. Clypeus and orbicles rather silvery. Prothorax bordered by a vertical Jamina in form of a crest, but which does not prolong itself upon the sides. Metathorax furrowed, with the coneavity bordered above and furnished with a pile of gray hairs, having a slight tawny reflection. Post-scutel unarmed. Swelling of the petiole neither cylindrical nor globular, but oval, and, as seen in profile, dilated above. Second segment ovate-globular, not enlarging itself as suddenly as in the Z cristatus; but it has no more length of pedicle, and the same silky, golden reflection.
Insect black; two dots on the forehead, border of prothorax, a spot under the wing, two on the scutel, the post-scutel, and the border of segments 1, 2, 3 orange-yellow. Wing-secales often touched with yellow. These colors offer the same variation as in the species cited; the crest of the vertex being often adorned with a yellow line, while the metathorax has no spots of this color.?
1 At least in my specimens. It will not do, however, to accept this as a constant character.
ZETHUS. BE
Feet black; tarsi rather ferruginous. Wings transparent, clouded, yellowish-brown, with the nervures brown—their reflection golden-gray.
%. Anterior border of the clypeus notched as in the female ; the angles of the indenture in the form of teeth, the middle tooth smaller than the lateral. All the clypeus covered with a silvery downs; its lower moiety of a yellow color, as well as a line upon the scape of the antenne. Mandibles yellow in front, the end of the antenne black, the hook elongate, edged, and sharp; the terminal joints sometimes a little rolled up.
Ress. a. diff.—It is a little smaller than Z. Westwoodi, and is distinguished from it by its more swelled and more coarsely punc- tured petiole, by its more indented, more strongly punctured elypeus, ete. It has the form of Z. spinosus, but it has no post- scutellar spine, ete.; and although rather coarsely punctured, that is really less so than this species.
Hab. Mexico, on the gulf side. Tampico.
Fig. 1. The male enlarged. Fig. 1, a. The head of the male seen from before. |
Observation.—The figure 1 is not entirely satisfactory: the head not sufficiently thick, and the second abdominal segment with the pedicle a little too long.
23. Z Otomitus n. sp.—Niger, dense punctatus; capite et thorace cinereo-, abdomine fulvo-hirto; antennis nigris, scapo linea flava; punctis 2 frontalibus, pronoti margine, fascia post-scutelli, abdominisque segmentorum 1-3 linea marginali, flavis; petiolo ovato-tumido nitido, punctato, apice truncato, superne impressione transversali; genibus et tarsis fuscescentibus; alis fusco-aureo nebulosis.—% elypeo trapezino, fascia submarginali flava.
Total length, 14 mm.; wing, 10 mm.
%. Quite the same form and punctuation as Z. aztecus. But the clypeus not square, more triangular, wide inferiorly, narrowed at the summit, or rather in the form of a half cirele, a little con- vex, densely punctured; the inferior margin wide and transverse; with a wide transverse emargination and two little teeth. A pale yellow band oceupies the inferior part, but the extreme margin is black. The flagellum of the antenne quite black; only the hook is sometimes brown beneath. The lateral carinwe of the metathorax a little more pronounced ; the petiole not so coarsely punctate, a little wider behind, more truneate, somewhat as in
38 HYMENOPTERA OF AMERICA. [PART i,
spinipes; the 2d segment without any impression before its border; scutel black; no macula under the wing. The interme- diate femora have no yellow fasciz. The wings are washed with brown, with a golden reflection; the 2d cubital cell generally triangular; its radial side wanting or quite short.
Clypeus and head gray-silky; abdomen golden-silky as in Z. aztecus. °
Hab. Mexico; the Oriental Cordillera. Orizaba. (6 % sent by Mr. Sumichrast.)
It is not without hesitation that I separate this species from Z. aztecus; but the clypeus is decidedly of a different form, and the coloration is quite the same in my six specimens, seeming to in- dicate a decided species.- The end of the antenne is quite black as in Az/ecus.
24. Z chrysopterus Savss.-—Niger, ferrugineo-hirtus, stature Z. Westwoodi; capite latiore quam longiore, dense—punctato. Thorax valde punctatus, reticulato-rugosus ; pronoti margine cristato, angulis prominentibus ; scutello sulco partito; metanoto levi, hirsuto, postice foveola distincta, carinis longitudinalibus 2 marginata instructo. Petio- lus ovato-cylindricus, inflatus, parte lineari basali brevissima ; secun- dui segmentum globoso-dilatatum, vix pedunculatum, fulvo-velutinum. Puncta 2 frontis et pronoti angulorum abdominisque segmentorum . limbus anguste flava; tarsi ferruginei; ale subferruginee, tegulis piceis vel flavo-marginatis. Longit. 0.017.
*. Clypeo punctato, dimidio inferiore aurantiaco, margine tenuiter nigro, bidentato.
Zethus chrysopterus Sauss. Vespides, I, 13, 8, pl. viii, fig. 7, 4%, 1852; Revue Zool. X, 1858, 66. Hab. Probably from South America. (Typus in auctoris museo. )
25. Z. ferrugimeus Satss. Zethus ferrugineus Sauss. Vespides, I, 14, 10, 1852.
Hab. South America. Para.
26. Z. cimerescems Savss. 9.—Niger, cinereo-sericenus; eclypeo plano, punctato-striato, bideutato; capite dense punctato; thorace eri- brato, striato-rugoso, antice cristato, angulato; post-scutello truncato; metanoto postice producto, rugoso, lateraliter cristato-carinato; in medio foveolato sed haud bicarinato; petiolo brevi, globoso-clavato, haud cribrato; abdom. secundo segmento subsessili, sed piriforme-dilatato (haud globoso), sericeo.—Puncta 2 frontis, pronoti margo, post-scutellum
ZETHUS. 39
et petioli limbus frequenter flava; tarsi fusci; ale infuscat#, secundum costam nigre, tegulis ferrugineo-marginatis. Lougitudo, 0.015.
Zethus cinerascens Saugs. Vespides, III, 117, 3, 1554.
Hab. Brazil. (2 2 in museo auctoris; typus in museo Tau- riueuse. )
Z. fraterno affinis, at differt pronoto cristato et angulato, thorace rugose, petiolo minus punctato et globosiore.
The male is not known; some doubt still exists about the place this species must occupy.
23. Z. Dighwumnis SPin.
Zethus biglumis Srixoua, Ann. Soc. Ent. Fr. X, 1841, 135, 83.—Saoss. Vespides, I, 19, 20.
Hab. Cayenne.
28. Z. discoelioides Savss.—Niger, capite et thorace valde cri- brato-punctatis, punctis confluentibus rugosis; clypeo rugoso, cri- brato, subbidentato; pronoto cristato-marginato, biangulato; scutello sulco partito ; metanoto supra foveola striata instructo, cujus margines laterales fere cariniformes sunt; abdominis primo segmento brevi, ovato- campanulato, inflato, truncato, valde punctato; secundo segmento piri-— formi, sericeo.—Tegule ferruginee; frons et post-scutellum fiavo-bipune- tata; petiolus flavo limbatus; pedes fuscescentes ; ale paulum infuscate, aureo-nitentes. 9.—Longit. 0.013.
Zethus discelioides Sauss. Vespides, I, 17,! 17, 1852.
Hab. South America. Para.
Species moderately stout—viewing its short form and strongly inflated petiole—and resembling to some extent Z. cinerascens, though its 2d abdominal segment is less pyriform and the elypeus more strongly punctured and not distinctly striate.
This species, in view of its petiole, campanulate and truncate rather than contracted behind, might almost be placed in section 8. (This form shows itself also among the Z. spinipes.)
B. Species which have more the appearance of Eumenes or Discelius. Head less inflaled, less hollowed out at the occiput; thorax of moderate length;
petiole more as in the EHumenes (f Division a.
' Last line of this page (of Vespides), instead of Zethus, read Disewlius.
40 HYMENOPTERA OF AMERICA. [PART I.
29. Z. Montezuma Sauss. (Fig. 3, 3a.)—Parvulus, rugosus, niger et pilosus; abdomine ovato ut in genere Humene; petiolo elongato perrugoso; religua parte abdoiminis piriformi, depressa; pronoti, post- scutelli et abdominis segmentorum 1, 2, margine, flavo vel ferrugineo ; scapo, macula subalari et seutelli, margineque clypei, flavis.
Zethus Montezuma Sauss. Revue Zool. IX, 1857, 270. Z. Guatemolzin Sauss. ibid. (var. Q ).
@. Total length, 13 mm.; wing, 10 mm. *%. Total length, 10 mm.; wing, 8 mm.
©. Insect small, slender; head but little inflated. Ocelli ina regular or even lengthened triangle. All the head rugose, crib- rose with coarse punctures; clypeus entire, also cribrose, convex and rugose. Thorax lengthened, one and a half times longer than wide, cribrose with large punctures, rugose; on the disk of the mesothorax two arcuate grooves leave the scutellum, and extend to the anterior suture. Angles of the prothorax spinose; its margin relatively little prominent. Metathorax attenuated, con- vex, rugose, but with a lateral, very distinct truncation. Petiole quite lengthened, its anterior third, at least, linear; the remainder enlarged, pyriform, much lengthened and truncate, rugose, cribrose with very large punctures (larger than those of the thorax) ; its en- largement but little raised, hardly contracted behind, its marginal depressions forming a transverse groove. ‘lhe remainder of the abdomen depressed, regularly pyriform, lengthened as in the Eumenes, at the base sub-pediculate, gradually swelling; the second segment shining, polished, silky-gray, delicately punctured, more coarsely along its border.
Insect black, very hairy, even its abdomen being covered with a pile of erect hair in fresh specimens; hair of the head and thorax obscure; that of the metathorax and of the abdomen gray. Inferior and lateral border of the clypeus often ferruginous ; a line under the scape of the antenne, two dots at their insertion, inargin of the prothorax, a point under each wing, two at the scutellum, two on post-scutel, and the border of the first two abdominal segments yellow or ferruginous. ‘These markings are variable, the scutellum being often black and the post-scutel yel- low; or the markings are entirely wanting. Wing-scales brown or ferruginous. Wings hyaline, nervures brown, and often a brown cloud in the radial cell.
%. Smaller. Clypeus transverse, black, covered with silky-
ZETHUS. 4]
gray hair; its inferior margin carrying in the middle a very small notch, above which is a little yellow. Antenne a little tawny at the extremity, terminated by a hook and by a slight rolling up. Metathorax spotted with yellow; anterior border of prothorax often black.
Var. a. Clypeus and scutel black; no spot under the wing.
b. At bottom of metathorax two yellow spots.
c. A yellow line in front of the mandibles.
Ress. a. diff.—This species is recognizable by the particular form of its abdomen. The lengthened petiole, longitudinally linear, becomes suddenly campanular; the second segment gradu- ally swelled, so that the abdomen is pyriform rather than globular- ovate. The lengthening of the thorax and the head a little en- larged, recall the forms of the Humenes.'. The metathorax, also, presents no concavity; the position of the furrow is, however, indicated, and it is ragose and striate, but is convex in place of being excavated.
This insect appears to be allied to Z. discelioides.
Hab. The temperate regions of Mexico: Ihave taken it in the valleys of Cordova, of Orizaba, and of Mextitlan (four females, five males).
I possess one specimen, a §, as small as the %, and which is ¢ little more strongly punctured, which has the petiole shorter in the linear part, and is sensibly more coarsely punctured in its enlarged part. The scutellum and post-scutel each have two yellow spots. Length, 0.010; wings, 0.008.
Is this a variety of Z Montezuma, or a species? I have taken it on the banks of the Rio Panuco, in the Huasteca.
Fig. 3. Zethus Montezuma, 9, enlarged. Fig. 3, a. The head 9 seen from before.
30. Z. parvullus Savss.— 9. Parvulus, gracilis, niger; clypeo con- vexo, apice truncato, late subemarginato; pronoto cristato-marginato, utringue angulato; post-scutello carina arcuata antrorsum convexa in- structo, metanoto anguloso, supra carinulis 2 sinuatis e post-scutelli angulis emergescentibus et postice convergescentibus, instructo ; petiolo gracili, in medio campanulato, punctato; secundo segmento paulum in- fundibuliformi.—Caput et thorax dense punctata, argenteo-sericea ; an- tennarum articulis 1-3 subtus, genibus, tibiis et tarsis, ferrugineis ;
1 And slightly also those of the genus £limus.
42, HYMENOPTERA OF AMERICA. [PART i
petioli margo flavo-notatus; ale secundum venas infuscate. Longit, 0.011.
Zethus parvulus Sauss. Vespides, III, 119, 5, pl. ii, fig. 1, 9,1 1854.
flab. Brazil. South of the Province of Goyaz. (Collected by the savant botanist Auguste de St. Hilaire.)
This species approaches to the form of Z. Montezuma; but it is much less coarsely punctured, smaller, and very clearly recog- nizable by the arcuate ridge of the post-scutel, which in com- tinuation of the carinz of the metathorax, forms a prominent horseshoe.
y- Petiole quite linear, filiform, depressed, very much elongate, as in Eumenes of Division. The appearance of a Calligaster.
3. Z. strigosus n. sp.—lNiger, fulvo-sericeus, parum flavo-ornatum; pro- et mesonoto valde oblique strigatis ; metanoto rugoso; petiolo lineari ; 20 segmento basi breviter pedunculato; pedibus nigris, flavescenti- pilosis; alis subhyalinis.
Q. Total length, 14 mm.; wing, 11 mm. %- Total length, 12 mm.; wing, 8} mm.
?. Slender. Head strigate-punctured. Prothorax sharply margined, angular on each side, but not spined, obliquely strigose. The whole disk of mesothorax strongly obliquely strigose and wrinkled; the strise converging against the middle carina. Scutellum shining punctate, a little sulcate in middle, as the post- scutellum. Metathorax rugose, velutinous, wrinkled on each side, at base parted by a channel; the lateral cauthi carinated on the sides. Petiole very long and slender, not globulously swollen, but quite linear (as in Humenes of Division Zeta) flat- tened, shining, and parted by an impressed line, punctate on the sides. Collar of the 2d segment distinct; the hinder margin of this segment very slightly reflexed.
Black, furnished with a yellowish-silky, or rather golden pubescence; the metathorax and pleura with cinereous pubescence. A line on the base of the inner margin of mandible, a line on the scape, two dots on the front, a very narrow line on both margins of prothorax, the post-tegula, angles of post-scutellum, and two
1 The male of this species is not known. It is possible that it should be placed in section d.
ZETILUS. 43
fascise on metathorax yellow. Scales margined with brown; a narrow yellow submarginal line bordering all the segments of the abdomen; the 6th segment yellow. Feet black, knees a little fulvous; tibia furnished with silky-golden hairs. Intermediate tibize with a yellow line. Wings subhyaline, with brown veins. On each side of the clypeus is a very dull, obsolete, yellow macula.
?. Clypeus rounded, a little truncate at tip, punctured, rugose, black.
%. Clypeus broad-quadrate, strongly punctured, slightly truncate in the middle of its inferior margin, with two hardly sensible edges; black; the lateral yellow spots often distinct. Antenne rather thick; the whole terminal hook and the last three joints of the flagellum beneath, yellowish.
Var. &.—a. Clypeus yellow, with the top part and extreme margin black; sometimes also with two black dots on the yellow.
b. Clypeus more or less margined with yellow.
Var. & .—a. The spots of the forehead wanting.
b. The posterior margin of the prothorax not margined with yellow.
c. The anterior margin having only the angles yellow, or also a little line in the middle.
d. Prothorax black.
Hab. The Gulf side of Mexico. Orizaba. (Sumichrast. )
This species, although very variable in its coloring, is very distinct by its filiform pedicule and by the strong strigze of its dorsum. It has the facies of an Llimus.
C. Species which I do not know, and of which the antenne 3, have not been described.!
32. Z. albopictus Smirn.— 9.. Niger, sat tenuiter punctatus; cinereo Sericeus; antennis subtus apice ferruginescentibus ; clypeo utringue flavo-notato; pronoti margine, macula subalari, punetis 2 in tegulis, scutelli margine interrupto, punctis 2 post-scutelli tibiisque extus, albidis; abd. segmentorum 1-3 limbo et lineola (utrinque?) in basi
secundi, albidis; alis pellucidis, secundum costam fuscis. Longit, 43 lin,
' As the form of the abdomen has not been described, I presume that it offers nothing remarkable, and that in consequence all these species per- tain to the division Zithusculus,
44 HYMENOPTERA OF AMER‘ICA. [ PART iF Zethus albopictus Smrru, Cat. Brit. Mus. Vespide, 1857, 15, 32.
Hab. St. Domingo.
So. Z. gracilis Smira.—Niger, capite et thorace grosse punctatis; fronte sulco transverso inter antennas et carina verticali ad medium clypeum producta instructo; metanoto in lateribus striato; petiolo Sparse punctato ; abdomine sericeo ; punctis 2 frontalibus abdominisque segmentorum limbo anguste, flavis. 4% antennarum scapo antice flavo. Longit, 43 lin.—Affinis videtur, Z. Wontezume.
Zethus gracilis Smitu, Cat. Brit. Mus. Vespide, 1857, 17, 43.
Hab. Mexico. Small species, of the size of Z Montezume.
o4. Z. laevimodus Smiru.—. Niger, capite grosse, vertice sparse, punctato; clypeo rugose striato, apice subemarginato; thorace polito, punctis distantibus aliquot; pronoti margine acute marginato, acute angulato; mesonoto antive carina abbreviata, et sulcis 2 e scutelli angulis emergentibus ad pronotum ductis; metanoto velutino, bi- convexo. Thorax maculis 2 in pronoti angulis, macula-subalari, post- scutellique fascia interrupta, flavis; abdomine polito; alis fusco-cyaueis. Longit, 9 lin. \
Zethus levinodus Smita, Cat. Brit. Mus. Vespide, 1857, 17, 44. Hab. Mexico. By the fuscous wings this species comes near to Z spinipes,
but is separated from it by its distinctly polished mesothorax, and by its remarkably large size.
oo. Z. pallidus Smiru, Cat. Brit. Mus. Vespide, 1857, 11, 10. Hab. Brazil. (Num Zethusculus?)
36. Z. scuipturalis Smiru, ibid. 11,11, %. Hab. Brazil.
Ze Ze aubius SMITH, ibid. 13, 19; °) % . Hab. Brazil.
38. Z. carimatus Smirz, ibid. 13, 20, 4. Hab. Brazil.
ZETUUS. 45
Division DIDYMOGASTRA Perry. (Sauss. Vespides, I, 18; ILI, 120.)
Second segment ef the abdomen lengthened pediculate ; its pedicular part forming at least a fourth of the length of the seg- ment. The other characters as in Zehusculus.
These insects have very slender forms on account of the extra- ordinary length of their abdomen, by the double articulation of which, they enjoy the singular faculty of folding the abdomen beneath the thorax, and of placing the terminal pear against the face of the head.
The Didymogastra inhabit the hot regions of America.
One cannot establish any line of demarcation between the Zethusculus and the Didymogastra; these last form the continua- tion of the same genera and only represent the more lengthened modification of the type. The two series, based on the form of the antenne of the males, continue themselves in the Didymo- gastra. So this division is wholly empirical, and should not be preserved except to facilitate the determination of species.
A. Antenne of the males terminated by a rolled spiral.
29. Z Poeyi Sauss. (Fig. 4, 4a.)-—Niger, rugose punctatus, metanoto vix striato, velutino; petiolo polito, tenuiter punctato, gibboso ; secundo abd. segmento levi, nitido, pedunculo mediocriter elongato; mandibulis, frontis fascia, orbitis bis interruptis, pronotoantice, maculis 2 subalaribus, tegulis, scutello et post-scutello antice, maculis 2 metanoti, petioli apice pedibusque, aurantiacis; his rufo vel nigro variis ; abdomine ultra peti- olum rufo; alis flavescentibus, apice grisescentibus.
*%,. Fronte earinato; clypeo aurantiaco, emarginato, bidentato; mandibulis flavis; antennarnm articulis 1-2 rufis, fascia flava; flagello subtus flavo- annulato, apice cochleato, flavo.
Zethus Pocyi Sauss. Revue et Mag. de Zool. 1857, 270.
Total length, 14 mm.; wing, 10 mm.
b
Head and thorax quite densely cribrose (moderate and a little irregular often, in form of an oblique prick of pin). Ocelli pro- minent, arranged in a rather large triangle. Vertex $ forming a ridge in form of a T, of which the vertical limb touches the clypeus. The posterior part of the vertex a little more elevated than the ocelli. Thorax contracted before, its margin little
46 HYMENOPTERA OF AMERICA. [PART I.
salient. Scutellum punctured with coarse points, ane divided by a groove. Metathorax punctured on each side of its summit, neither punctured nor striate on its posterior face, but velvety. Enlargement of the petiole convex; its swelling, seen in profile, is more salient near its base, and is depressed and contracted behind; on its extremity is an excavation. This enlargement, seemingly smooth and polished, is quite finely punctured. Second segment very shining and polished, its pedicle equalling a third of its length and widening posteriorly; the globular bell, as long as wide, enlarging gradualiy. Seen in profile, it is much more swelled above than beneath.
Insect black, with orange markings, which are in general arranged as follows: sinus of the eyes, the transverse bar of the frontal T, a point on the summit of each eye and the orbit behind the eyes; the prothorax, wholly or in part, a spot under the Wing, wing-scale, the anterior portion of the scutellum and of the post-scutel, two spots on the metathorax and the extremity of the petiole, orange. These markings are more or less developed; they may be more extended, or in part wanting. The remainder of the abdomen is of a beautiful red or ferruginous, with the base of the pedicle black. Scape of the antennz ferruginous. Feet yellow, varied with ferruginous. Wings ferruginous, with the end lightly gray, carrying a little reflection of violet.
2. Clypeus rounded, black, with two oblique yellow bands at the superior margin; 2d joint of the antenne ferruginous; a whole band of yellow under the wing; the margin of the 2d abd. segment narrowly yellow.
%. End of the antenne rolled spirally. Clypeus orange, finely punctured ; its inferior border armed with two separated teeth, with an arcuate border between them, in the middle of which is a little salient tooth, often hardly visible. The first two and the last two articles of the antenne orange; the flagellum annulate with this color beneath; the terminal spiral orange; the last article obscure.
Var. The specimens of other localities possess, without doubt, more of black on the abdomen and antenne. ,
Ress. a. diff.—Vhis Didymogastra is easily distinguished from Z. Chicotencail, by the rugose aspect of its head and thorax, by its much less striate metathorax, by its petiole more swelled
ZETHUS. 47
above, distinctly punctured; by its second segment with its less extended pedicle, and by the yellow markings of all the body.
It differs from 7. Matzicatzin, in its smaller size, in its much more lengthened thorax, having a mesothoracic disk longer than wide; in its metathorax, devoid of middle carine and of smooth spaces at the superior angles; in its scutellum, simple, depressed, angular (not emarginate) posteriorly; in its less enlarged and more punctured petiole, and in its head smaller, without swelling of the vertex.
The % differs in its celypeus, quadrate, large, convex and notched as in the Z Poeyt, not flattened and advanced in the middle as with the Matzicatzin; by the antenne terminating in a spiral, by the ocelli placed upon a scarcely oblique plane, etc.
Hab. The island of Cuba. This beautiful insect was given me yee roel. Ioey. |
Observation.—In the figure, the thorax is too large and the form of the abdomen is not perfectly natural.
40. Z% Romamdimus Savss.—Niger, cinereo-sericeus, capite lato, dense punctato; thorace grosse cribrato, antice cristato-marginato ; scutello convexo, sulco, bipartito; metanoto convexo, haud foveolato, velutino, tenuiter punctato, supra utrinque spati» nitido levi; petiolo dense punctato, nitido, postice paulum attenuato, flavo-marginato, secundo segmento sat breviter pedunculato tanqnam in Didymogasira, piriformiter dilatato, marginem versus tenuiter punctato, tenuissime flavo seu ferrugineo-limbato ; reliquis punctatis, piceo-limbatis; tegulis ferrugineo marginatis, pedibus, fuscescentibus; tibiis intermediis flavo- variis; alis diaphanis, subfuscescentibus.
?. Clypeo transversim quadrato, flavo, tenuiter bidentato; antennis sub- tus apicem versus flavo-annulatis et apice cochlea fulva.
Longitudo, 14 mm.; ale, 10 mm.
Zethus Romandinus Sauss. Vespides I, 20, 22, pl. ix, fig. 1, 9, 1852. Revue de Zool. X, 1858, 164. °
Hab. Cayenne. (Typus in auctoris museo. )
This Zethus constructs with woody fibres and gummy materials several rounded cells, with thick walls toward the bottom and irregularly united, recalling a little those of Bombus (see Sauss. Vespides, I, pl. ix, fig. 1, ¢). The instinets of these insects appear to progress toward the habits of the Social Wasps.
|
48 HYMENOPTERA OF AMERICA. [PART I.
4i. Z. aurulentus Savss.
Zethus aurulens Sauss. Vespides, III, 121, 8, pl. vi, fig. 5, 9, 1854. Hab. Brazil.
42. Z. Matzicatzim Savuss.—Niger; capite discoidali, lato, facie cribrata, vertive supra inflato, minus cribrato; ovellis in deelivitate frontis sitis; thorace grosse cribrato, postscutello truncato, postice ex- ciso, carinato; metanoto sulco conspicuo, at foveola nulla; infra valde striato, supra levi, in medio bicarinato; petiolo polito impunctato, vaide inflato, apice puncto maximo impresso; secundo segmento longe pedun- culato, medio margine impresso, cum reliquis rufo; tertio punctato, in medio producto; punctis frontalibus et post-ocularibus 2, pronoti margine, macula subalari et maculis 2 scutelli, limboque segmentorum
4
i, 2, flavis; tibiis rufis; alis fusco-flavescentibus. *%,. Secutello plano, tenuiter punctato, infra macula levi et margine in medio subproducto; antennarum scapo subtus flavo.
Zethus Matzicatzin Sauss. Revue et Mag. de Zool. 1857, 271.
Total length, 18 mm.; wing, 11 mm.
Mandibles obliquely truncate, trenchant, without teeth, but with a single lobe. Head very large, much wider than thorax; face flattened; ocelli arranged in a broad triangle and placed, not on the summit, but on the slope of the vertex. Vertex strongly enlarged transversely behind the ocelli, but swelled upward. Face-offering between the antenne two little vertical carine. Thorax very short, quadrate, depressed; the margin of the prothorax little prominent. Disk of the mesothorax wider than long; its anterior curve describing a semicircle, not an ellipse as in all the preceding species. Scutellum divided by a channel. Post-scutel truncate, angulate; its posterior border offering a concavity and carrying an arcuated ridge interrupted in the middle (which especially distinguishes it from the preceding species, which has the post-scutel whole rounded above). Meta- thorax very angulate, haying four sharp ridges, so to speak: Ist, the two ordinary lateral ones, which here form two sharp crests ; 2d, two other very short ones, which start from the angles of the post-scutel; the middle divided by a strong channel, but, properly speaking, without any concavity. The summit of the metathorax, especially the space situated on each side between the two ridges, is smooth, shining, not punctured (or very finely striated), the remainder wrinkled. The flanks under the lateral ridges smooth
ZETHUS. 49
and shining. Petiole quite lengthened-pediculate; its elliptical enlargement is globularly swelled above, as high as wide (sub- compressed), having on its posterior extremity above, a large excavation, and on each side a large transverse groove, which compresses the end of the petiole, hut without coalescing with the middle groove. Second segment lengthened-pediculate, almost as in the Z. Chicotencati; its globular part very flat beneath, and much swelled above from its base; its first posterior border a little sinuous, preceded in the middle by a vague depression—its second border not being at all reflected. Margin of the third segment formed in the same way, but the first border more sinuous, Head coarsely punctured; the face cribrose, but the vertical inflation very much less. Thorax cribrose with sunken points, except the metathorax. Petiole and abdomen smooth and shining, while the last is very finely punctured. The third segment punctured. .
Insect black, garnished with a gray or slightly golden pile; two spots on the face, one behind each eye; margin of the prothorax, a point under the wing, two spots on the scutellum, and the borders of the Ist and 2d segments, yellow. The abdomen, except the petiole, of a brown purple or ferruginous. Feet black, varied with ferruginous. Wings washed with brown-yellowish, nervures brown; wing scales bordered with brown or yellow.
%. Clypeus very flat, punctured; its inferior margin advanced in the middle, entire ; a smooth lozenge or triangle in the middle of its inferior extremity ; this piece is black, covered with gray hair—its lozenge-shaped part smooth, often yellow. Antenne black, with front of the scape yellow and terminated by a little ferruginous hook.
Ress. a. diff.—See the affinities of Z. Chicotencatl and Poeyi.
The Z. niger offers also two metathoracic carine starting from the angles of the post-scutel; ‘but in this species the post-seutel is not crenulated, and there is between these carine a concave pit, while here the two moieties of the metathorax remain convex and are separated by a deep furrow. The thorax and the head are also smaller, ete.
Hab. The gulf side of Mexico. Tampico. I have taken but one specimen (4%).
By the very remarkable form of its clypeus and its mandibles,
4 .
50 HYMENOPTERA OF AMERICA. [PART T.
this species deserves to be noted as fit to serve as the type of one section of this genus.
B. Antenne of % terminated by a hook.
43. Z. Milariamus Savss.—Gracilis, niger; capite dense punctato, supra et pone oculos tumefacto; thorace minus dense punctato; pro- noto valde cristato-marginato, sed angulis haud acutis ; mesonoti disco carinis 2 levibus trajecto; post-scutello medio subdentato; metanoto velutino, rugoso, striato, in medio canaliculato; abdominis petioli tumefactione ovata, sat globoso-inflata punctulata; secundo segmento globoso, sericeo, basi sat longe petiolato (petiolus tertiam partem longi- tudinis efficiens); segmentis reliquis punctatis. Corpus omnino velu- tinum, argenteo-sericeum; puncta frontalia 2, macule 2 post-oculares, antennarum articuli 1-3 et apex, thorax, petioli latera et pedes, rufa; petioli apex et lineola utrinque in secundi segmenti petiolo, flava; seg- mentorum limbus tenuiter piceus vel rufus. Ale infuscateg, costa nigra. Longit, 0.016 mm.
Q. Clypeo convexo, punctato, apice late subexciso, tridentulato; maculis 2 lateralibus rufis.
%. Clypeo truncato, rufo vel flavescente macula media et basi nigris, vel nigro margine infero rufo et laterali flavo; anteunis apice ultimo minuto rufo.
Var. Color variabilis, plus minusve rufescens vel nigrescens; disco mesonoti obscuro vel nigro, carinis rufis; etc.
Zethus Hilarianus Sauss. Vespides, III, 120, 7, pl. vi, fig. 6, 9, 1854.
Varies in having the margin of pronotum and the post-scutel yellow, and in the distribution of colors, the reddish and black passing one to the other; but, nevertheless, a distinct species by its mesothoracical carine.
Hab. Brazil. Middle of the province of Goyaz. (The type is in the Paris museum.)—Venezuela, Caracas.
44. Z. gemiculatus Serv.
Didymogastra geniculata Spin. Mem. Acad. Turin, XIII, 1853, 80, 60. Zethus geniculatus Sauss. Vespides, I, 22; III, 120, 6.
Metanoto postice bicarinato; colore affinis Z. nigro.
Hab. Brazil. Para. (Typus in mus. Taurinense.)
45. Z. dicomboda Srin.—Niger, gracilis, dense punctatus, cinereo- sericeus; pronoto autice cristato-marginato, angulato; mesonoti disco bicarinato; metanoto convexo, velutino, haud rugoso, in medio striato.
ZETHUS. 51
Abdomen gracile, petiolo elongato, parum inflato, punctato, apice puncto impresso nullo; secundo segmento sat longe pedunculato, ovato-dilatato, depresso et tenuiter punctato.—Puncta 2 frontis, pronoti et tegularum 'margo, post-scutellum, fascie 2 metanoti et abd. segmentorum 1-2 margo, nee non fascia utrinque petioli secundi segmenti (vel petioli apicis) albida; femora intermedia subtus albido varia; ale# hyaline, venis ferrugineis, apice grisco-nebulose. Longit, 0.015 mm. ©. Clypeo nigro, rugoso, truncato, sub-bidentato (vel sub-tridentato). %,. Clypeo albido, supra nigro, margine infero bidentato, tenuissime nigro limbato; antennis nigris, uncinatis. Epipona dicomboda Spinoua! Gay’s Historia fisica de Chile (Fauna Chi- lena), VI, 1851, 250. Zethus discomboda Sauss. Vespides, I, 21, 25.
Hab. Chili. (Typi in museo Parisiense et in auctoris servantur. )
C. Species of which the section remains undetermined.
AG. Z@ Chicotemcatlh Savss. (Fig. 5, 5a.)—Niger, politus, fulvo hirtus, clypeo convexo, capite dense punctulato, thorace levigato, in medio disco nitido, impunctato; pronoto antice et pone angulos in lateribus cristato-marginato; metanoto haud excavato, ubique rugose striato, petiolo parum inflato, impunctato, nitidissimo, secundo segmento longe pedunculato, sericeo, secundum marginem punctato, margine sub- jacente reflexo; antennis subtus flavis; punctis 2 frontalibus, maculis 2 metanoti, et abdom. segmentorum limbo (aliquandoque pronoti), tibiisque supra, flavis; alis ferruginescentibus. Q.,
Zethus Chicotencatl Sauss. Revue et Mag. de Zool. 1857, 271.
Total length, 17 mm.; wing, 12 mm.
2. Mandibles strongly tridentate. Clypeus rounded, very convex, but finely punctured, truncate or sub-bilobed on its in- ferior border, in the middle of which is a smooth space. Head densely punctured, but not rugose. Ocelli salient, placed in a regular triangle on the vertex, the head a little contracted behind. Thorax shining and polished, not being punctured above the middle; margin of prothorax forming a salient lamina; this margin reflexes upon its angles and prolongs itself behind, along the lateral border of the prothorax over a moiety of the distance from the wing seale. Mesothorax punctured along the seutellum, without groove on its hinder part, but carrying a double longi- tudinal groove on its anterior moiety; seutellum convex and shining, feebly punctured. Metathorax a little flattened behind,
52 HYMENOPTERA OF AMERICA. [PART I.
having a very small groove, strongly striated transversely or rather channelled in all its superior and posterior surface (situated above the lateral ridges). Some striz, but less distinct, also cover entirely the lateral faces of the metathorax, beneath the angles. Enlargement of the petiole in an oval form, much lengthened, depressed, without. any globular swelling above; its linear portion short, equal to a third the length of the petiole, smooth, shining, without punctures. The posterior depression not having an excavated point, but a transverse shining channel. Second segment much lengthened, pediculate; its pedicle form- ing almost the moiety of the length of the segment, which offers a zone of fine punctures along its posterior border; the second lamina of this margin a little reflected. The whole insect is covered with a tawny pile almost woolly on the thorax, gray on the metathorax, a little golden on the abdomen, but the body is polished and shining, especially the petiole, which does not show any punctures.
Color black; antenne ferruginous beneath, obscure above. Two dots on the face, two spots on the metathorax and often the post-scutel and the margin of the prothorax, yellow or tawny. Petiole having a yellow interrupted border; the abdominal segments wholly or in part margined with a very narrow yellow line. Feet black. Tibix yellow before. Wings transparent, washed with yellowish-gray.
Ress. a. diff.—This species appears to me very near to Z. tubulifer. It may even be identical; which I dare not say posi- tively, not having the type of this last before my eyes, and being without a sufficient description.
It is very recognizable hy its back as well as its petiole, being without punctures and shining. The Z. Chicotencail is not diffi- cult to distinguish from the Z. Matzicatzin, by its metathorax, rugose even to the summit and without middle carine, by its post- scutel, which is not notched behind, by its much less enlarged petiole, by the border of its second segment, which is punctured, and by the second Jamina of its border, which is turned up; _per- haps also by its thorax, which is not cribrose, and by the ocelli, which occupy the summit of the vertex.
Hab. The gulf shore of Mexico. I have taken it at Tampico. (The Z. tubulifer comes from Orizaba in the Cordilleras.)
A, 2
Or
ZETHUS.
/
Observation.—In the figure the petiole is not quite suddenly enough enlarged, aud the profile of the pedicle of the second segment is a little too short, as also in the linear part of the petiole.
4%. Z tubulifer Savuss. Vespides, I, 18, 19, 9.—Niger: clypeo rotundato; antennarum scapo subtus ferrugineo-notato ; pronoto angu- lato; punctis 2 frontalibus, pronoti margine, tegulis partim, maculis 2 scutelli, fascia interrupta post-scutelli, maculis 2 metanoti, margine lineolaque laterali utrinque petioli apicis, segmentorum margine punc- tisque coxarum, flavis; pedibus flavo-variis; alis fumosis. Longit, 0.017-18.
Hab. Mexico. Oriental Cordillera.
48. Z Zemdalus n. sp.—Niger, punctulatus, capite et thorace griseo-sericante; metanoto tenuissime strigato; pronoti fascia, macula subalari, maculis 2 scutelli, 2 metanoti, petioli apicis lineolis 2 laterali- bus, et lineolis 2 lateralibus 2' segmenti basis, citrinis; segmentis reli- quis late rufo-marginatis; ano rufo. 9
©. Total length, 14 mm.; wing, 10-11 mm.
Head and thorax densely and delicately punctured. A little compressed brilliant point between the antenne. Prothorax margined, but not angulated. Metathorax velutinous, very delicately strigate, divided by a channel. Petiole ovate, narrow, very delicately punctured like the abdomen, destitute of an im- pression at the end. Peduncle of the 2d segment rather long.
Black, with grayish hair; the margin of prothorax, a spot under the wing, two on the scutel, two elongate maculz on the metathorax, and a sinuous lateral line on each side of the extremity of the petiole, a line on each side of the peduncle of the 2d seg- ment, and two dots at its base, lemon-yellow; a broad fascia on the margin of segments 2d—5th, and the 6th segment, orange- yellow or rufous. The apex of the petiole has no yellow margin and no groove, but the base of the peduncle of the second seg- ments has two yellow dots, which can be easily taken by error for a yellow marking of the apex of the petiole. Feet black. Wings smoky with a golden reflection, the nerves black.
2. Clypeus rounded, densely punctate, black like the antenne and mandibles.
Ress. a. dif?.—Distinet from Matzicatzin by its moderate head, absence of impression at the end of petiole, and absence of
54 HYMENOPTERA OF AMERICA. [PART I.
carine on the middle part of the metathorax. Differs from Chi- cotencall by its prothorax not crested on the sides, its petiole narrower, etc. It comes very near to Romandinus, but the thorax is shorter anteriorly, more narrowed posteriorly; the petiole narrower, less inflated, ete.
Hab. Mexico. The Oriental Cordillera (Mr. Sumichrast).
49. Z%. miscogaster Savuss.—Q. Minutus, niger, dense punctatus, cinereo hirtus; clypeo integro, rugoso, piloso; fronte inter antennas transversim carinato; ocellis in summo fronte sitis. Thorax antice cristatus, carinatus, humeris haud spinosis; postscutello et metanoto haud rugosis, velutinis, hoe tenuiter. striato, nec carinato, nee distincte foveolato, sed sulco profundo diviso. Abdomen politum, sericeum ; petiolo elongato, parum inflato, supra parum gibboso; secundo segmento longe pedunculato, ovato-dilalato subdepresso. Caput immaculatum ; pronoti margo, macula subalaris, macule scutelli et 2 metanoti, lineola utringue, petioli apex, limbus secundi segmenti, lineolaque utrinque in basi pedunculi, flava. Ale subpellucide, venis fuscis.—Longit. 0.015.
Z. discombode similis at minor, et pronoto haud angulaso differt. A Z. Romandino differt statura graciliore, petiolo minus punctato et minus tume-
facto.
Zethus miscogaster Sauss. Vespides, I, 18,18, 9, 1852. Zethus microguster (per errorem) Sauss. Revue Zool. X, 1858, 163.
Hab. South America. (Typus in auctoris museo.)
&O8. Z. bimodis Fasr.—Gracilis, niger, dense punctatus. Caput Jatum, dense cribratum; clypeo rugose cribrato, integro. Thorax eribratus, cristato-marginatus, clypeo convexo, nitido, eribrato; postscutello haud cribrato, postice truncato, sed cantho acuto nullo; metanoto in medio foveolato, carinis prominentibus duabus e postscutelli angulis emergen- tibus ; spatio extra carinam sito utrinque valde striato-plicato ; usque ad canthum lateralem acutum. Abdominis petiolo polito, tenuiter pune- tato, sat ovato-tumefacto, apice utringue flavo-notato; secundo segmento globoso, longe pedunculato, ubique tenuiter punctato, sericeo seteso, in medio margine impresso; tertio, in medio margine paulum producto; 2° et 3° tenuissime flavo-marginatis; reliquis piceis vel ferrugineis. Tibie 1, 2, ferruginee. Ale subhyaline. Longit, 0.017.
Vespa binodis Far. Ent. Syst. Suppl. 1798, 264.—Coquzs. Iust. Icon. Ins. pl. xv, fig. 2.
Eumenes binodis Fasr. 8. P. 287.
Zethus binodis Sauss. Vespides, I, 20, 23.1
! Typus in museo Parisiensi.
=
ZETHUS. 55
Zethus niger Sauss.'’ Vespides, I, 1852, 21, 24, pl. viii, fig. 9.2
A Z. Romandino differt metanoto carinato, foveolato et plicato; petiolo globosiore et minus valde punctato; secundo abd. segmento globosiore, magis pedunculato, et punctatiore; segmentis 3-5 minus punctatis; tertil margine in medio producto.
Hab. Cayenne.
ol. Z didymogaster Srin. Zethus didymogaster Spin. Ann. Soc. Ent. Fr., 1841, X, 133, 9.
Hab. Cayenne.
This species differs from Z. binodis in its very wide clypeus, having a straight border, armed with two distant teeth. (Has not the author taken a male for a female? Only the males have the clypeus twice as wide as long.)
o2 BZ. fuscwus Perry.
Didymogastra fusca Pury, Delect. Anim. Artic. 145, pl. XXVIII, fig. 5, 2 , 1830. Zethus fuscus Sauss. Vespides, I, 19, 21; III, 120.
Hab. Brazil. Amazon.
5d. Z. Sumitiaii Savss. Zethus Smithii Sauss. Vespides, III, 122, 9, 9.
Metanoto striato; alis fusco-cyaneis.
Hab. South America.
SPECIES WHICH I DO NOT KNOW.
The following species of the genus Zethus, all from Brazil, have been described by Fred. Smith in the Catalogue of the Vespidx of the British museum, page 11-18.
4. pallidus Z. carinatus—albopictus
seulpturalis—dubius.
gracilis—levinodus.
! Typus in auctoris museo. 2 Errata. Fig. 8, pl. viii, Vespides, I, does not represent this species, but Z. piriformis.
56 HYMENOPTERA OF AMERICA. [PART I.
Gen. LABUS Saoss. Labus Sauss. Reise d. Oesterr. Fregat. Novara. Hym., p. 3.
Mandibles short, obliquely truncate, with 3-4 terminal teeth. Maxille elongate; their palpi elongate, 6-jointed. Labiwm elongate, quadrifid, its palpi 4-jointed. Head rounded, swelled at the occiput; clypeus rounded or truncate.
Thorax elongate; its anterior angles sharp.
Abdomen very slender; its petiole elongate, linear. Wings somewhat as in Humenes and Zethus.
As the forms of the insects of this type are becoming various, one could well think that the genus Zabus might be fused into G. Elimus, which only differs from this by another form of thorax and petiole. Such differences occur under the species of the genus Zethus.
A. Petiole filiform at base, a little widened posteriorly; its extremity margined by a transverse rounded cordon pre- ceded by a transverse channel (as in Eumenes of Division Omicron). Second segment sessile, elongate. Metathorax attenuated. Head inflated. Second cubital cell much pro- longed at the basilar extremity; the second recurrent vein inserted after the middle of its posterior border. (Asiatic type.) i. Spiniger Sauss., L. Humbertianus Sauss.
B. Petiole linear, slender, prismatic; 2d segment subpedicu- late. Thorax elungate; metathorax short; prothorax crested anteriorly. Second cubital cell equally dilated at both extremities; second recurrent vein inserted in the middle of its posterior border. (American type.)'
=
1 The genus Elimus would make a third type :—
C. Petiole linear, rather thick (very elongate, somewhat pyriform), biden- tate; its extremity marked with an impressed point; head moderate ; thorax oval, not acute angled anteriorly; metathorax rounded; the 2d segment elongate, rather attenuate posteriorly ; 2d cubital cell in a regular truncate triangle; second recurrent nerve inserted in the middle, or a little before the middle, of its posterior border.
LABUS. 5Y
1. UL. Sicheliamwus n. sp. (Fig. 20, 14a.)—Niger, gracilis, thorace elongatiusculo, antice eristato-marginato, superne crassiuscule punctato; petiolo lineari-prismatico; 20 segmento basi subpedunculato; capitis maculis, pronoti margine antico, maculis 2 scutelli et 2 metanoti ab- dominisque segmentorum marginibus, flavis.
Total length, 11 mm.; wing, 8 mm.
©. Antenne rather clubbed. Head quite orbicular, rather swelled and rounded at the occiput, densely punctured; a little carina between the antennz. Mandibles short truncate, armed with three terminal teeth, tricarinate at end. Clypeus ovate, as wide as long, a little truncate at tip, covered with coarse punctures, substrigate. Ocelli disposed in an equilateral triangle. Thorax a little depressed, flattened above, rather ovate (that is, elongate), rounded posteriorly, a little contracted anteriorly, truncate and margined with a crest; the angles of prothorax salient. The thorax above strongly punctured, not so strongly on the sides; the metathorax a little shagreened; the lateral faces of this not punctured. Metathorax having its posterior face vertical, somewhat truncate, triangular, but quite arcuate at the summit, and margined by a little arcuate ridge, rough and obso- lete; the hind face parted by a depression and a little strigate in the groove. Disk of mesothorax elongate, having two arcuate furrows. Petiole elongate, quite linear; only its base filiform ; the rest depressed and compressed, making it prismatic, with a dorsal, two lateral faces and an inferior face; the faces having scattered punctures; the superior one not parted by a furrow, but with a round impression before the border; the inferior one earinated; the lateral faces having the margin a little salient because of their compression; the compression being more sensible behind the middle of petiole, so that the anterior part of the swelled portion is a little wider than tlte rest and a little ovate. The rest of the abdomen nearly impunctate; the second segment globular, but its base a little funnel-shaped and articu- late by a very short neck as in the Zethusculus. Anterior tibiz very short.
Black, with short gray pile. Antenne a little ferruginous at the extremity beneath; a spot in the middle of the mandibles, a line on the scape, a spot on each side of elypeus, two dots over the insertion of the antenne, and one in the sinus of each eye,
58 HYMENOPTERA OF AMERICA. [PART I.
yellow. The anterior margin of prothorax, two marginal spots on each wing scale, post-tegule, two spots on post-scutel, two longitudinal fasciz on the metathorax, the end of petiole and the margin of the abdominal segment, yellow; the lamellar margin of these also yellow or ferruginous, as well. as the margin of the anus. A spot at the end of the femora and a line on the tibie of the first two pair, yellow. Wings subhyaline with brown veins; the 2d cubital cell subtriangular ; its radial tip very little trun- cate; the second recurrent nerve inserted in the middle of the posterior margin.
Less. a. diff.—This remarkable type has a certain resemblance to the Humenes of Division Zeta, because of its elongate linear flattened petiole; but this is not so much flattened, nor parted by a furrow, but prismatic, and the head with its short mandibles is quite that of a Zethus.
It has a very near relationship to the Asiatic Zabus but differs essentially by its prismatic petiole, a form which I have not yet met with in the Wasp.
Hab. Chili. (This insect was given to me by the celebrated oculist and remarkable entomologist, Dr. Sichel, to whom it is dedicated. )
Gen. DISCGELIUS Latr.
Lip moderate. Labial palpi composed of four articles. Maz- illary palpi composed of six articles. JJandzbles short, obliquely truncate. Head often enlarged and a little emarginate behind. Thoraz lengthened, often angulate before. Abdomen pediculate;
the first segment transformed into a campanular or linear petiole.
This genus differs from Zethus by its labial palpi composed of four articles, and from Humenes by the mandibles which are not prolonged in the form of a beak.
This genus connects itself to Zethus by its mandibles, and to Eumenes and to Odynerus by its complete palpi; the forms of its representatives are also intermediate, in some degree, to Zethus and to Humenes, and somewhat to Nortonia and Zethus by the subpediculate abdomen. The form of the thorax, often bordered and angulated before, especially assimilates it to that which one sees in the Zethus.
EUMENES. 59
i. D. merula Corris. Discelius merula Curtis, Trans. Linn. Soc. XVI, 325, 1834.—Saovss. Vespides III, 124. Epipona chilensis Spin., Gay’s Mist. fisica de chile, Zool. VI, 248, 1851. Discalius chilensis Sauss. Vespides, I, 25, 1, 1852. Discalius Spinola,! Sauss. Vespides, I, 25, 2, 1852, III, 124.
Hab, Chili.
2. D. pulchelius Savss.—9Q. Parvulus, punctulatus; elypeo piri- formi; apice truncato; pronoto antice biangulato, metanoto rotundato ; petiolo brevissimo, campanulato grosse punctato; apice puncto impresso ; abdominis secundo segmento nitido, supra inflato.—Insectum nigrum,
» mandibulis puncto basali, clypei apice macula nigra, fascia frontali, puncto post-scutellari, scapi fascia antica, flavis; antennarum flagello subtus ferrugineo; pronoto antice, tegulis, scutellis et metanoto, flavis, (sed puncto in tegulis et matanoti sulconigris;) abdominis segmentorum li 2' limbo et secundi maculis 2 lateralibus, flavis; pedibus flavis, fusco-variis; alis hyalinis, stigmate et areola radiali fuscis, costa fus- cescente.
*%. Mandibulis et clypeo flavis; hoc apice subbidentato, antennarum uncino minuto ferrugineo.
Discelius pulchellus Sauss. Vespides, III, 127, 15.
Hab. Mexico; Jamaica.
Legion il. The Odynerites.
Mandibles more or less lengthened, terminating in a point, forming generally by their union a long sharp beak, or when crossed, an X. Their teeth placed on their inner border ( Vide Saussure, Vespides, I, p. 27, 11).
Gen. EUMENES Fasr.
Organs buccate, very long. Tongue long, a little plumose. Galeas (or appendices) of the jaw very long. Palpi lengthened; labial composed of four articles; the maxillary of six. Mandibles very long, sharp pointed, having a triturating lateral border and forming by their union a lengthened beak. (In exceptions the
mandibles are sometimes shorter.)
a - - eet
1 A variety of Chilensis.
60 HYMENOPTERA OF AMERICA. [PART I.
Head much compressed transversely, that is, wide, but not thick, nor enlarged; the eyes very convex and entirely covering the cheeks. Clypeus always longer than wide, with a variable termination (bidentate, indented, truncate, or rounded).
Thorax variable, globular, or long quadrate, rarely compressed, but always without spiniform angles.
Abdomen lengthened pediculate. The first segment forming a linear or subcampanulate petiole, about as long as the thorax;
the remainder of the abdomen pyriform.
This genus is very abundant in species, and is found over all the surface of our globe. It is broken up into peculiar types, of which one (Division Alpha) is represented everywhere, and the others solely on one part of our planet. These types are con- nected by natural transitions which embarrass one in assigning them very fixed limits.
The Lwmenes are well represented on the new continent. Of six divisions' into which I have divided the genus, four are found on the Western Continent, but the divisions Pachymenes, Omicron, and Zeta, are only represented in the tropical parts of America. The insects, peculiar to the Division Omicron, inhabit all the equinoctial parts of the continent; and those which belong in the Division Alpha, extend themselves over the two American continents within their most extended limits.
Division PACHYMENES. (Sauss. Vespides I, 73, III, 153.)
Abdomen much depressed, never compressed, petiole widened or campanular, parted by a groove; its hinder margin having usually a transverse groove; clypeus generally bidentate ; body smooth, silky, and chatoyant or velvety; wings large. (American type.) |
These insects have the appearance of Polybia, as the Monte- zumia have that of Syneca. It is especially by this appearance that one recognizes them and the semblance holds good in the depressed form of the petiole and in the pyriform abdomen as well as the silky appearance of the body.
! IT do not count the Division Pareumenes, which is worthy to form a genus (Etudes sur la Famille des Vespides, III, 133).
EUMENES. 61
Among certain species, the thorax becomes narrow, lengthened, compressed, and the metathorax is sometimes lengthened, so that the resemblance to the Polybia increases. Although the Pachy- menes present a series of forms corresponding to those which one sees among the Polybia; yet one can easily distinguish them from these social insects by their truncate or bidentate clypeus, which is not angularly terminated by a sort of tooth.’
This group is not as yet well studied; most. of its species, which appear to be rather numerous, are only known by rare specimens scattered about in collections which have much simi- larity among themselves, all having a silky body and colors pale or variable, so that one can easily confound them.
Unfortunately it is impossible for me here to establish good differential characters between these insects, from only knowing some of them by unique specimens and not having under my eyes the types of all species heretofore described.
I established the genus Pachymenes in the monography of solitary wasps to receive those Humenes of which the clypeus is bidentate, the abdomen depressed, and of which the smooth and satin-like body recalls the appearance of Polybia. But I have now renounced this section, so difficult to define, although includ- ing insects of a very peculiar appearance; for since that time I have found many American Humenes having the clypeus biden- tate at the end, while certain Pachymenes have a bidentate petiole, which destroys one of the differences on which the genus Pachymenes was founded. I have, therefore, undertaken to reduce the consideration of this generic group to that of a sim- ple division of genera, and this division itself goes over into the division Omicron so that it is impossible to fix a refined limit between them. (Hx. &#. Santa-Anna goes over to division Omi- cron and is quite close to LH. levis.)
1. Form rather lengthened ; thorax longer than wide; abdomen hardly depressed, the 2d segment not campanular.
A. Petiole campanular, enlarged above beyond the middle,
' In my Monographie des Guepes Solitaires, I have confounded certain species of Polybia described by Fabricius with the Pachymenes. See Vespides, III, p. 158. (On the line before the last of that page, for chry- sothorax, read pallipes.)
62 HYMENOPTERA OF AMERICA. [ PART I.
humped, the boss divided by a groove ; its extremity bordered by a salient band.
a. Thorax rather compressed, lengthened.
4. E. sericeus Sauss.—Gracilis, fusco-niger; thorace compresso; pedibus, petiolo et thorace supra ferrugineo-fulvis ; hoc valde fulvo- . velutino; alis subhyalinis, costa fusca. Q.
Pachymenes sericea Sauss. Vespides, I, 74, 1 (Syn. excl.) ; pl. xii, fig. 5; Til, 153. /
Total length, 19 mill.; wing, 15 mill.
2. Slender; thorax compressed, rather narrow anteriorly. Head black; clypeus bicarinate at the extremity, bidentate or notched; the inner orbits and a line behind the eyes rather yel- lowish. Antenne at tip a little ferruginous beneath. Thorax blackish, but having its upper parts ferruginous or ornamented with yellowish, and all covered, as well as the sides, with velvety fulvous hair, rather woolly, which makes it quite fulvous. Petiole slender, ferruginous velvety; its base brown, its extremity a little obscure with a more yellowish border; the rest of the abdomen of a brown-olivaceous color. Feet ferruginous, more or less brownish or yellowish.
Ress. a. diff—Very much resembles auratus, from which it differs principally by its quite woolly, velvety hairy thorax and ~ by its less bidentate clypeus.
Hab. Brazil. Bahia. (Paris museum.)
2. E. auratus n. sp.—Fulvo-olivaceus ; capite fusco; clypeo biden- tato, apice testaceo-marginato; thorace aureo-sericeo, compresso, meta- noto valde angusto, sed pronoto antice haud coarctato, petiolo campa- nulato, gibboso, suleo subpartito, apice puncto impresso, basi nigro; mandibulis, orbitis, prunoti marginibus, mesonoti et metanoti fasciis 2, scutellis, tegulis et macula subalari, frequenter testaceis ; alis paulum ferrugineis. ©,
Total length, 17 mill.; wing, 13 mill.
2. Insect slender, of an olive-brown, rather velutinous. Head blackish, with the orbits somewhat bordered with testaceous; clypeus flattened, a little bicarinate, toward the end strongly bidentate ; its teeth spiniform, separated by a triangular notch; its extremity and its inferior border yellow-testaceous, as weil as the mandibles. Antenne ferruginous beneath, especially toward
EUMENES. 63
the end. Thorax convex, strongly compressed, strongly con- tracted toward metathorax, but not on the prothorax, which is squarely truncate. All the corselet covered with a silky golden- yellow pile; the posterior border of the prothorax and its anterior margin about the angles, two bands on the mesothorax, two on the metathorax, scutels, wing scales, and a spot under the wing testaceous. Abdomen olive-brown, silky, having an olivaceous reflection; petiole campanulate in the middle; its dilated part carrying a boss terminated by a groove, its border limited by a rim or rounded band. Its linear part black at the base and a little testaceous, second segment oval, lengthened, depressed. Legs varied with testaceous; wings transparent, ferruginous, with the extremity griseous.
fess. a. dif/,—This species resembles the ZH. olivaceus in the form of its head and of its abdomen, but its thorax is more com- pressed, more narrow and lengthened in proportion; the meta- thorax is much compressed and is not bicarinate.
It may be that this is a variety of the ZH. sericeus of which the woolly hair of the thorax has been rubbed off?
flab. Brazil. Bahia.
&. KH. chrysothorax Savss. Pachymenes chrysothorax Sauss. Vespides, III, 153, 43.
Hab. Brazil. (Typus in museo Parisiensi. )
This species, of which I cannot again examine the type, is most likely a var. of 7. sericeus. It is proper to notice that the forms should be those of LZ. pallipes.
b. Thorax not compressed, moderately wide.
4. BH. pallipes Savss.—Fusco-olivaceus ; capite nigro; antennis apice subtus ferrugineis; clypeo bicarinato, apice bispinoso, testaceo; orbitis partim, mesonoti fasciis 2, scutellis, metanoto superne pleurisque, flavo- testaceis ; pedibus ferrugineis; alis ferrugineis, apice fusco-nebulosis ; petiolo sat dilatato, superne tumido, ante marginem canaliculato. 9°. Longit. 17 mm.
Pachymenes pallipes Sauss. Vespides, I, 75, 3 (Syn. excl.) ; III, 153.
This species is not so slender as the preceding ; the petiole is wider. he insect is probably sericeous when living.
Var. Prothorax bordered with testaceous
The colors are certainly very variable.
Hab. South America. (Paris museum.)
64 HYMENOPTERA OF AMERICA. [PART I.
5. E. olivaceus n. sp.—Olivaceo-fuscus, clypeo valde bidentato, apice flavo-testaceo; thorace aureo-sericeo, antice quadrato, metanoto superne bicarinato ; petiolo tumido sulco partito; ‘antennis subtus, tegulis et tarsis, ferrugineis ; orbitarum maculis fascia interrupta post-scutelli tibiisque extus testaceis; alis diaphanis, ferrugineis. 9.
Total length, 20 mill. ; wing, 15 mill.
Brown-chocolate or olive. Head and antenne blackish. Head and thorax very delicately punctured, sericeous; prothorax broad and square; metathorax narrower, short, having in its superior part two carine which start nearly from the angles of the post- scutel. The whole thorax with a golden reflection, velutinous principally on the metathorax. fPetiole pyriform-campanular, swelled above, parted by a delicate groove, bordered by a cordon preceded by a transverse groove. The rest of the abdomen depressed—pear-shaped ; the 2d segment rather elongate.
Antenne ferruginous beneath, principally at the extremity ; wing scales and tarsi ferruginous. Mandibles, a line behind each eye, and often the inner orbits testaceous. ‘Tibiw, knees, and cox varied with pale yellow; an interrupted line of this color margining the post-scutel. Borders of prothorax often ferrugi- nous owwith golden reflections. Wings transparent, ferruginous.
?. Clypeus oval, black, scarcely punctate, ending with two carine in two long teeth, separated by a triangular notch; its extremity and inferior margins yellow-testaceous.
Ress. a. diff—This species much resembles #. obscurus and ater, but differs by its metathoracic carine. It differs from £. brunneus by its scrolled, swelled, and bordered petiole.
Hab. Surinam. This species has been communicated to me by Capt. Von Heyden from the Senkeaberg Museum at Frank- furt (Germany).
6. E. obscurus Smirx.—Validus, niger, sericeus; clypeo apice biden- tato; mandibulis, flagello, pedibus anticis subtus, pronoti margine postico tegulisque, ferrugineis; alis hyalino-ferrugineis. 9.
Pachymenes obscura Smitu, Cat. Brit. Mus. Vespid., 34, 7 (1857). Total length, 22 mill.; wing, 18 mm. 2. Black. Clypeus pyriform, having a triangular notch at its
extremity, and bidentate; often two little carine terminating in the apical teeth. Mandibles long, slender, a little arcuated at
EUMENES. 65
tip. Thorax rather square shaped anteriorly, not margined. Petiole campanulate, rather short; its dilatation broad, swollen superiorly; the longitudinal channel quite obsolete, only distinct on the anterior part of the dilatation. The rest of the abdomen depressed.
The whole body very smooth; head and thorax very finely punctured, covered with a fine fulvous silky pubescence. Man- dibles, flagellum of the antenne, fore legs beneath, posterior margin of the prothorax and wing scales, ferruginous; the borders of the abdominal segments often brownish or ferruginous. Wings transparent-ferruginous with brown nervures; their apical part griseous. |
Var. a. Legs, knees, etec., rather ferruginous.
b. Abdomen quite black.
c. A little ferruginous spot under the wing; two dots on base of antenne.
d. An interrupted ferruginous line on the post-scutel and two obsolete lines on the mesothorax.
e. Metathorax and scutels marked with ferruginous (obscura Smith),
Jj. The general color brownish.
g. The emargination of the clypeus more or less pronounced ; the eclypeus not bidentate, only a little emarginate at tip.
h. A yellow mark on each side of the clypeus.
Ress. a. diff.—This species much resembles LZ. ater, but the thorax seems to be shorter and thicker. It differs from Aztecus by its shorter petiole, of which the dilation is more triangular, less elongate, and by its clypeus destitute of spines. Compare Ef. ater.
Ilab. The temperate parts of Mexico. Orizaba. 6 9.
“%. KE. ater Savuss.—Niger, obscure-sericans ; clypeo bidentato, sul fureo- marginato; orbitis partim, post-scutelli fascia interrupta et petioli margine, sulfureis vel ferrugineis.—% tibiis flavo-variis.
Pachymenes atra Sauss. Vespides, I, 75, 2; III, 153.
Total length, 20 mill. ; wing, 15 mill.
Form nearly as in 2. obscurus ; clypeus bidentate in the same way; the same punctuation, but a little smaller in size. The metathorax clothed with gray pile. The petiole not quite so
5
66 HYMENOPTERA OF AMERICA. [PART I.
much dilated posteriorly, having on its hinder part a very obso- lete wide channel. The thorax shorter, more convex; the ante- rior margin a little bordered.
Black, with a fine sericeous reflection; flagellum of ile antenne beneath, principally at tip, Pra cine an interrupted line. on the post-scutel and on the hind margin of the petiole, yellow. The end of the femora and the tibie a little tinged with yellow. Wings ferruginous.
2. The emargination and the lateral borders of the clypeus, a line along the orbits inside and at top outside, sulphur-yellow ; mandibles in part and the tarsi, ferruginous.
Var. The mesopleure marked with ferruginous; the end of the clypeus not yellow. Margin of segments brownish.
%. Antenne terminated by a little brown hook. The yellow ornaments of clypeus more extended. Mandibles black; tibiz with a yellow band.
Var. No yellow border at the petiole.
Ress. a. diff.—This species differs from Olivaceus by its metathorax, which is not carinated.
Hab: Brazil. Bio Janeiro. 2,2, 2 %.
B. Petiole pyriform, depressed, less inflated above, not divided by a@ groove.
S. E. Samta-Anna. (Fig. 6, 6a.)—Niger, politus, vel punctulatus, argenteo-sericeus;clypeo bidentato; metanoto brevi, convexo, abdomine depresso ; puncto frontali, pronoti margine postico, et antice fascia inter- rupta, scutelli margine, post-scutello, maculis subalaribus, et segmen- torum abdominis 1, 2 limbo tibiarumyue fascia, luteis; alis fusco- venosis.—Valde variabilis species.
Eumenes Santa-Anna Sauss. Revue. et Mag. de Zoolog., IX, 1857, 272. Total length, 16 mill.; wing, 11 mm.
Of medium size. Body polished, nearly impunctate. Ocelli arranged on. an arcuate line. Clypeus bidentate; its teeth spiniform. Thorax wide and quadrate before; very slightly bordered anteriorly; its angles a little rounded. Metathorax short, convex, as among the true Humenes, polished and punctate. Abdomen much depressed. Petiole nearly of the length of the thorax, campanulate, smooth, and shining, its posterior moiety very wide and strongly depressed, its posterior border thickened
EU MENES. 67
in a marginal cordon, which is preceded by a transverse groove ; the convexity not divided by a longitudinal furrow. Second segment short above, nearly wider than long; its posterior border not turned up. The metathorax has its lateral faces plane and obliquely cut.
Insect black, little or not at all punctured, but smooth, shining, and garnished with a silky pile of gray hair, which gives it a satin-like or silvery appearance. A line on the scape, a little dot on the face, a line behind each eye, posterior border of prothorax along the curve of mesothorax, an interrupted border on the anterior margin of prothorax, two spots under the wings and a point on each side of the summit of the metathorax, anterior border of the scutellum, post-scutel, and border of segments 1, 2, of a sulphur-whitish color, generally a lateral yellow spot smelted with the border of the petiole. Antenne black, ferruginous beneath. Legs black, the tibis marked with a yellow line. Wings transparent, with the nervures, the costa, and the radial cell brown. Wing scales red or brown; their appendicular scale yellow at the extremity.
2. Clypeus margined with yellow on each side.
Var. Clypeus black; the scape only tawny beneath.
%. Hook of the antenne long and ferruginous. Clypeus black, argenteous.
Var. a. No spots on the metathorax. The spots of the thorax more or Jess complete. This part of the body often passing into brown. ‘The flagellum ferruginous beneath.
Hab. The gulf side of Mexico. Tampico. Orizaba, Cordova.
SUS ee
2. Thorax short, globular. Petiole somewhat funnel-shaped, much lengthened; 2d segment almost the shape of a globular bell. Body velvety, bristling with hair.
9. E. vemtricosus Savss.
Pachymenes ventricosa Sauss. Vespides, I, 77, 5, pl. xii, fig. 7.
Var. a. Second ‘abdominal segment not margined with yellow. b. Wings very dark with brown reflections. Hab. South America. Sante Fé de Bogota (not Carolina, as
a false ‘étiquette” made in print). Venezuela,
68 HYMENOPTERA OF AMERICA, [PART 1.
Division OMICRON. (Sauss. Vespides, I, 71; IL, 133, 148.)
Body sericeus. Clypeus @ bidentate, often bicarinate. Thorax very short, cubical before, globular behind. Petiole very elongate —pear-shaped, not campanulate in the middle, swollen into a polished boss at the extremity; its margin bordered by a polished cordon, preceded by a transverse channel or constriction, but without impressed point at the extremity; the marginal cordon forming a simple yellow (or black) line, without indentations as in Division a. ‘The rest of the abdomen more or less depressed, never compressed, often polished. Second abd. segment having its colored border followed by a second lamellar margin; second cubital cell short. Antenne of males with a very small terminal hook, or even quite destitute of hook, as in the females.
Ornaments.—The colored border of the posterior margin of prothorax more pronounced than the anterior one; fasciz gene- rally not wide. The petiole often ferruginous in the middle and on the sides, its hind margin with a yellow band, and often also ornamented on each side by an oblique yellow line fused with the yellow border.
This section only contains species of small size. The head and the thorax are very large compared with the abdomen; they are sometimes cribrose with great punctures and covered with a silvery pile, in place of being hairy, sub-woolly as most species of the Division Alpha. The clypeus is more or less bidentate, never distinctly truncate, and the ocelli have a tendency to arrangement in a straight or arcuate transverse line. The emargination of the eyes is situated very low, almost in the middle of their height, and these organs entirely cover the sides of the head, which is short. The antenne are inserted very low, sometimes below the middle of the head.