rb t .HoS^H'Ll "Bn T MANUAL OF ^ORTH American Diptera BY SAMUEL W. WILLISTON Third Edition JUuBtrat^h NEW HAVKN JAMES T. HATHAWAY 297 CROWN ST. NEAR YALE COLLEGE 1908 1'^1 / #• Copyright, 1908, BY SamukIv W. W11.1.1STON. fC.^ t t c-V • • J » • » 1 - « ••• » ,'f »*• .-c ,- » ♦" PREFACE. Twenty-four years ago the writer began the publica- tion, in the Bulletin of the Brooklyn Entomological Society, of a series of synoptic papers on the families and genera of North American Diptera, Previous to that time but seven of the sixty odd families had thus been rendered accessible to the American student in the works of Loew and Osten Sacken. In 1888 these synopses were revised and published, with others, in a pamphlet of 88 pages entitled ' Synopsis of the Families and Genera of North American Diptera, exclusive of the Nematocera and Muscidse.' It contained tabular defini- tions of about three hundred and fifty genera, all at that time known from the United States in the families treated. In the succeeding eight years the writer's acquaintance, especially with the southern forms, had been so widened that he attempted a similar review of all the North and Middle American genera, aided by Professor Aldrich in the Dolichopodidse and Mr. Snow in the Ortalidse. Re- gretfully the very large and almost chaotic families Dexiidse and Tachinidae were not included. Eight hun- dred and twenty-six genera were defined in this 'second edition' more or less accurately, very nearly all of which, save those of the Dolichopodidae, had been studied by the writer in its preparation. The continued use of this work, both in America and abroad, has been very grati- fying to the author, a use that has made him the more desirous that a better and more complete edition should be prepared, one that would be of greater service to the amateur, whose interests have been paramount. For such an edition the present time seemed opportune, since the recently published catalogue of the Diptera of North 4 NORTH AMKRICAN DIPTERA. America, by Professor Aldrich, a very meritorious work, has lessened materially the labor of its preparation, and must add to its usefulness. It was with some misgivings, however, that the author undertook the no inconsiderable task, since his studies for some years past have been almost wholly in a widely different field from that of entomology — vertebrate paleontology, a subject which, indeed, has absorbed the larger share of his attention for the past thirty years. But, he would not have undertaken the task, save upon the kind assurance of assistance and contributions by several of the leading students of diptera in the United States. The chief progress during the last twelve years has been in comparatively few families, the most of which had been but indifferently well studied at the time of the publication of the second edition; a progress in large part due to the work of the present contributors. Professor C. F. Adams has kindly aided in a large part of the work, especially the Cyclorrhapha, though the writer assumes all responsibility for changes and ad- ditions not directly accredited to the several contributors. Professor Adams has also furnished the tables for the very difficult families Dexiidse and Tachinidse, omitted in the previous edition. As in the former edition, the characters and table of the Dolichopodidae are wholly the work of Professor Aldrich; he has also generously assisted in other wa3^s, and it need not be said that, with- out the aid of his Catalogue, the labor of revision would have been greater, and the results less satisfactory. Mr. C. T. Brues, who has given so much critical attention to the singular family Phoridse, has furnished the char- acters and table of that family; one needs to compare his table with that of the former edition to see how much has been done in that group. Professor James Hine has re- vised the characters and table of the Tabanidae. Professor PREFACE. 5 O. A. Johannsen has furnished a new table of the Chiro- nomidse. Professor V. L. Kellogg has done the same for the Blepharoceridse, and has revised the family charac- ters. Professor A. L. Melander has treated the Kmpididse anew; and Professor C. H. T. Townsend has generously criticised the figures of the Dexiidse and Tachinidse, and has furnished important notes on many of the genera. To all these gentlemen the author tenders his sincerest thanks, not only on his own part, but also on the part of those who will have occasion to use the work. At the outset it was not contemplated to give many illustrations, chiefly such as would be explanatory of the more important characters. In the end more than six hundred genera have been defined more or less fully and decisively by nearly one thousand figures. Of these figures all those of the Dolichopodidse and the first plate of those of the Tachinidse were furnished by Professor Aldrich. Mr. Brues has furnished the figures of the Phori- dae. Professor Hine those of the Tabanidae, and Professor Melander most of those illustrating the Empididae. Pro- fessor Washburn kindly gave permission to use electro- types of twenty-three figures prepared for his or the late Professor Lugger's reports on Minnesota Diptera. To Professor Kellogg and Henry Holt & Co. the writer is indebted for eight electrotypes of figures in Professor Kellogg's American Insects; and to Professor J. B. Smith his thanks are due for six figures of the Culicidse, orig- inally prepared for his Report on the Mosquitoes of New Jersey. A few other figures have been copied from relia- ble sources, where specimens were not easily accessible, and are likewise credited in each case to its author. All the remainder, whether drawings or photographs, more than eight hundred in number, have been made by the writer from specimens — a task which has involved many months of labor, but which could not, in most cases, have been safely entrusted to a professional draftsman. 5 NORTH AMERICAN DIPTERA. To the authorities of the National Museum and Mr. D. W. Coquillett, the writer is indebted for the communica- tion of specimens of fourteen genera for purposes of illus- tration. Finally he has to express his hearty thanks to his friend and former colleague, Dr. F. H. Snow of the Uni- versity of Kansas, for the free permission to make use of whatever specimens were needed in the rich collections of that University — collections which include nearly all the types of diptera from the United States described by Townsend, Snow, Adams and the writer. Since the preparation of the present edition w^as begun has occurred the death of one whose name will ever be honorably associated with American Dipterology, Dr. C. R. Osten Sacken. The author can not forbear placing on record here an earnest tribute of friendship and ad- miration for the man, and unqualified appreciation of his work as an entomologist. His constant encourage- ment and kindly criticism during a correspondence of more than twenty 3^ears have made this book, whatever be its merits, possible; and the author only hopes that it may be found not unworthy of association with his work. It is with pain, also, that the author here records the death, in early years, of his friend and student the late Mr. W. A. Snow, who assisted in the preparation of the Ortalidae of the former edition. About twelve hundred genera are defined in the pres- ent edition, with the exception of a few doubtful forms, all those known from North and Central America and the West Indies. That the definitions are wholly with- out error is inconceivable. Whatever revision the book may receive in the future must be left to others, and, in taking final leave of it after these twenty-four years, the writer will be pardoned in repeating the words of a master, one whose works have served as models for this, Rudolph Schiner: 'Unci so uebergebe ich denii diese nieine Arbeit der OeffentHchkeit mil dem Wunsche, dass sie billigen Anfordernngen entsprechen inoege und mil dem Beifuegen, dass ich dem Urtheile unparteiischen L/eser mit voller Beniliigung entgegensehe, da ich bewusst bin, bei lyoesung meiner Aufgabe mit allem Eniste nnd der groessten Gewissenhaftig- keit vogegangen zii sein.' SAMUEL W. WIIylvISTON. University of Chicago, June, 1908. CONTENTS. Introduction .... Structure and habits of flies Morphology Head . Mouth-parts Antennae Thorax Legs . Abdomen . Wings ! Vestiture . Chsetotaxy Internal anatomy Classification of diptera Collection and preservation of flies Group characters and synoptic table or the eamiues of DIPTERA Famii^y characters and synoptic tabIvES of genera I Tipulidae II Psychodidse III Dixidae . IV Culicidse V Chironomidae VI Cecidomyidae VII Mycetophilidae VIII Bibionidse IX Simuliidae X Blepharoceridae XI Orphnephilidae XII Rhyphidae XIII Leptidae . XIV Stratiomyidae XV Acanthomeridae XVI Tabanidae XVII Cyrtidae . XVIII Neniestrinidae XIX Apioceridae 9 i6 20 20 24 27 31 34 36 37 43 45 49 51 62 65 81 92 94 96 no 117 131 140 144 148 153 155 157 164 173 176 182 186 188 8 NORTH AMERICAN DIPTKRA. XX XXI XXII XXIII XXIV XXV XXVI XXVII XXVIII XXIX XXX XXXI XXXII XXXIII XXXIX XXXV XXXVI XXXVII XXXVIII XXXIX XIv XLI XLII XLIII XlylV XI.V XL VI XIvVII XLVIII XLIX L hi LII IvIII LIV LV LVI LVII LVIII LIX LX LXI Appendix Index Mydaidae Asilidse . Therevidse Sceiiopinidae Bombyliidse Empididae Dolicliopodidae Phoridse . lyonchopteridse Platypezidse Pipunculidse Syrphidae Conopidae Tanypezidae Micropezidae Psilidae . Sepsidae . Ortalididae Rhopalorneridae Tr3'petidae Saproniyzidae Agromyzidae Geomyzidae Drosophilidae Ephydridae Oscinidse Diopsidae Borboridae Phycodroniidse Heteroiieuridae Scioiiiyzidae Heloniyzidae . Cord3duridae . Aiithoiiiyidae . Muscidae CEstridae Sarcophagidae Dexiidae . Tachinidae Hippoboscidae Streolidie Nvcteribiidae 190 192 205 208 2IO 218 228 240 241 244 246 261 264 264 267 269 271 280 282 288 291 297 299 303 310 314 315 317 318 321 324 327 331 337 344 348 352 358 382 384 386 387 391 NOETH AMERICA!^ DiPTERA. INTRODUCTION. The order of two-winged insects known as flies or Dip- tera includes more than forty thousand known species from different regions of the world. Since many of the species are small, or even minute, and inconspicuous, and since the order as a whole has not received the at- tention from collectors and students of entomology that other and more attractive groups have, it is very certain that many more await discovery. A very reasonable es- timate would place the entire number of species of flies at present in existence at more than eighty thousand. From North America the recent catalogue of Aldrich gives a list of about eight thousand species, distributed in more than a thousand genera. The subject is a wide one and replete with interest. To the student beginning the study of this interesting order of insects a few words of advice or caution Vlislj not be superfluous. The present work can make no preten- sions to completeness in the characterization of genera, at least in the majority of cases; that would require a work many times larger than is the present one, and is practically' impossible at the present time. One must not, therefore, depend entirely upon tables and figures in the absence of other information and other assistance, especially when he knows but few forms. If he does not immediately succeed in securely locating his specimens lO NORTH AMERICAN DIPTERA. he should nolf too hastily conclude that they are 'new'. Until he has acquired a considerable acquaintance with different families, the work of classification may at times be tedious, but by perseverance he can not fail to over- come whatever obstacles families and genera may pre- sent. He will be very much aided at the beginning by having a tolerabl}^ large collection at his command with which to make comparisons. Difficulties to the inexpe- rienced will often disappear with positive evidence before him, when negative characters would be doubtful. With each genus in a family positively determined, the diffi- culties and uncertainties of others will gradually disap- pear. Better still if he has numerous species reliably named with which to begin his studies. The present writer in his entomological career had few if any species or genera determined for him by others, and he well ap- preciates how wasteful of energies was such a method, at the time unavoidable. For full generic descriptions of many, perhaps the larger part, of the North American genera, the student will find a most valuable aid in Schiner's Fauna Austriaca, a work of which too much can not be said in praise. The descriptions are remarkable for their fullness, accuracy and simplicity, and, although the work is forty years old, it has lost but little of its value. To determine his species the student will need access to a large number of books and papers, lists of wdiich to the present time will be found in Aldrich's admirable and indispensable Catalogue of North American Diptera, published by the Smithsonian Institution. One must not, however, let the formidable lists frighten him. He will not need them all to begin with, nor even the larger part of them, and the earnest student can alwa3^s be as- sured of the sympathy and assistance of his fellow work- ers. His earlier determinations, and those of the student who is concerned chiefly in obtaining a broad general INTRODUCTION. n knowledge of the taxonomy of the dipteraj^may be con- fined, for the most part, to those groups which have been monographed, with full descriptions of genera and spe- cies, and, if possible with numerous illustrations. Refer- ences to the more important papers of each family will be found in Aldrich's catalogue. Long before the student has feached the dignity of 'independent research', he will have learned Vv^ho the masters of dipterology are ; who have shown the greatest acumen in the discernment and use of classificatory char- acters. It will not be invidious to distinguish above all others Schiner, lyoew and Osten Sacken as writers who can not be too faithfully studied, too closel}^ followed. Not that they are infallible ; none are. Indeed an error of a master is often more instructive than the masterpiece cf a dullard. One must learn the values of characters in classification before he can be successful in instructing others, or in making his discoveries known. And this knowledge can only be acquired by long and faithful study of living things and due reflection thereon. The narrow systematic specialist is looked upon som^ewhat askance by modern biologists, and rightfully too, but I have no hesitation in saying, and it is the experience of many years of study in different branches of natural his- tory, that the right kind of systematic work calls for the highest scientific powers of the student. I am aware that some narrow specialists in other departments of science will take exception to this statement, but I believe it and say it for the encouragement of those who may be dis- suaded from the earnest study of such creatures by the flippant remark of the shallow minded. But a mere col- lector of specimens, one who finds enjoyment in getting the largest number and arranging them in serial form in his cabinet is not necessarily a scientific student, though he may have a very pleasant and useful pastime; his la- J 2 NORTH AMERICAN DIPTERA. bors are scarcely more important than those of the micro- tomist who cuts up frogs' eggs and makes pictures of them. There are no principles too deep, no speculations too lofty to find application in such creatures as flies, the too often proletarians of the professional entomologist even. Most emphatically I would impress upon all students of dipterology who undertake the subject seriously, that the greatest need of modern entomology is monographic work. Nearly ever}^ family awaits the conscientious monographer, and such work is that which lasts longest and acquires most renown. The problems of distribution, of relationship, of origin, of the effects of environments, or the meaning and value of characters, can be satisfacto- rily solved by critical monographic studies only. The description of 'new species' as mere membra disjecta of faunas, is scarcely worth the energies of the earnest and careful student, certainly not as a life vocation, and none else has an}^ business to write at all. It too easily degen- erates into a mere roll-calling, a catalogue of the permu- tations of a few characters, increasing the difficulties for real students who come afterward. The name that an insect is known by is of trivial importance, and no one cares who described it, unless he did it poorly. It will be a fortunate thing when the search for 'new species' and the interminably haphazard making of 'new genera' is done. Even a cursory glance at some of the tables further on will convince the intelligent student that the real mean- ing of man}^ of the classificatory characters is yet imper- fectly comprehended. But little attention has been paid to homoplasy or 'convergent evolution', and as all true classification must depend upon the proper use of genetic characters, it is apparent that future revisions may ma- terialh' modify our present conceptions of relationships INTRODUCTION. 13 in many cases. I can offer no better example of this dis- regard for phylogenetic and convergent evolution than is shown in the proposed scheme of classification of the Cecidomyidse on later pages. The structure and use of the organs of orientation, — the antennae and palpi especial- ly, the further comparative study of the ocelli and eyes, the reasons for the evolution of the wing venation in ap- parently different systems, the causes of the variations in the patterns of coloration, the meaning more fully of the different kinds of vestiture, etc., etc., all need much more attention than has been given them by the systematist, and it is he who is best qualified to solve such problems. One of the first questions that a novice in classification asks is: What is a species, genus, family? The taxono- mist's answer to the first of these queries is easy: A spe- cies is a form of life with all its fertile variants. A mas- tiff and a grayhound are not distinct species of dogs, because there exist all possible variations between the two types, though both have bred true to themselves for more than three thousand years. But a dog and a fox are distinct species because there exist no varieties con- necting the two. If no two specim.ens in a given form of fly have precisely the same relative lengths of the anten- nal joints, then the relative lengths of these organs is not a specific character in that form. If, however, all the specimens occurring in Massachusetts have a definite relative length for each joint while these in Kansas have another, the finst impression is that they belong to dis- tinct species. If further discovery proves that, in cross- ing the country between Massachusetts and Kansas, the lengths gradually vary from one to the other, then we must consider the eastern and western specimens as mere- ly racial varieties of a single species. The systematist is never troubled as to what a species is, if he has all the material he wants. 14 NORTH AMERICAN DIPTERA. The answer to the second query, What is a genus? is, however, a very different matter. Ordinarily we might appl}^ the same criterion, that groups of species gradu- all}^ blending together should not be separated into two or more genera. But this will not suffice, since, because of the actual presence of the connecting links, the ex- tremes may vary enormously, far more than in many cases where the connecting links have disappeared, leaving the extremes isolated into easil}^ distinguishable genera. Both convenience and the demands of relationships re- quire here that such groups be broken up, though it may and often does entail the result that such genera may be ultimately distinguishable in their most allied species by only trivial characters. But the temptation offered here, especiall}^ to the narrow, perspectiveless specialist, is to use those same boundary characters, or their equivalents, as generic characters through the whole family, and the result is an almost innumerable number of proposed di- visions. As nearly every species of flies has some plastic or structural distinguishing character, it is very evident that we might ultimately reach the absurd result of mak- ing species and genera ^ coterminous. Between this ex- treme and the other, the grouping of large numbers of species into genera, all of which can be distinguished by decisive, if not important, structural characteristics, there must be a happy mean. This mean, however, must de- pend more or less upon the opinions of those best quali- fied to interpret them. In other words I am tempted to define a genus as being merely the personal opinion of its propose?'. By an excessive 'splitting' of genera, broader relationships are lost sight of, and the tendency is inevit- able to restore these evidences by the invention of new group terms to express them. Perhaps no better exam- ples of these tendencies are observable than in the more recently proposed classification of the mosquitoes. For INTRODUCTION. l^ many decades systematists were satisfied to distribute tlie known mosquitoes in a relatively small number of genera, genera which could be defined by characters equivalent to those used in the allied families of diptera. With the great impetus given to the study of these insects by the discov- er}^ of their agency in the spread of disease, the genera have been broken up into many new divisions, until sev- enty or eighty are now recognized by some students of the family. In the dearth of striking characters, those of extreme minuteness have been resorted to, such as the relative lengths and vv^idths of the scales and their distri- bution on the body; and even colorational characters have been called in aid. The obliteration of relationships thus brought about has rendered the erection of numer- ous subfamilies necessary, and it is even seriously pro- posed to elevate the previously accepted subfamilies to family rank, and the family Culicidse to a superfamily ! And I doubt not that some zealous confrere ma}'' yet se- riously propose to consider the old family Culicidae as a suborder! Possibly also, it may be necessary some time in the future to have a quantitative chemical analysis of a mosquito before deciding to which genus it may belong. Now it is very apparent that the importance of the mos- quitoes in man's economy can have no value in classifica- tion; that, if the happiness and welfare of every living being were dependent upon the mosquitoes it could not affect the classification of the family one whit ; but some- thing of the sort seems to have resulted. I will admiit that excessive 'splitting' of genera often brings to light and tests many differential characters which otherwise might long remain obscure. Neverthe- less, convenience is an important end of classification, as well as the expression of relationships. In days gone by the profuse maker of genera was ridiculed and the results of his labors were largely ignored; but I fear even Des- J 5 NORTH AMERICAN DIPTBRA. void3^'s shade would turn pale with envy in the contem- plation 'of some of the proposed genera of the modern culicidologists. STRUCTURE OF FLIES. The word diptera, b3^ which the two-winged flies are known, signifies two wings, the chief characteristic of the adult insects. All diptera, if they have any wings, have but a single pair. The hind pair of other insects is really represented by a small organ on either side, back of the true wings, consisting of a short, slender stem, terminating in a knob. The precise function of these 'halteres' or 'balancers', as they are called, if they have any, is not known ; that they have a secondarily acquired use is probable, since they are always in vibration during flight; an orienting or balancing function has been ascribed to them. The halteres are very character- istic of the order, always present in the winged forms, and usually present even in those in which the true wings are aborted or functionless, though rarely they are en- tirel}^ absent. Not all flies are winged, as has been al- ready intimated; rarely, among both the more general- ized and the more specialized groups they are imperfectly developed or wholl}^ wanting. Their absence is not of very great classificatory importance, never more than generic, and sometimes doubtfully that. Sometimes the male has wings and the female is wingless ; but the num- ber of wingless forms of any kind is very small. In size as well as in shape, flies vary not a little. As compared with the lepidoptera, orthoptera, neuroptera, and even the hemiptera, flies are relatively small insects. The largest specimen of a fly of which I have knowledge is that figured herewith natural size, pertaining to an indeterminable species of Mydas from South America. The length of this specimen from the tip of the antennae Fig. I. My das, species indet. lyife size. (Brazil. Fig. 2. Acanthomera, species indet. L/ife size. (Venezuela.) INTRODUCTION. 17 to the extremity of the abdomen, is sixty-seven millime- ters, or, omitting the antennae, fifty-two millimeters; the expanse of wings one hundred and seventeen millimeters, or a little more than four and one-half inches. The smallest dipteron that I have ever observed in the examination of many thousand specimens and five or six thousand species, is that of a cecidomyid measur- ing a trifle less than one half millimeter, also omitting the antennae. In other w^ords, the Mydas is more than one million times the size of the cecidomyid. Possibly there are still greater discrepancies between the largest and smallest specimens of the order, but in all prob- ability not much. The largest insect known is one allied to the dragon flies, an extinct Devonian species which measured about fifteen inches in length. As- suming that the bodily proportions of the largest and smallest hexapods are not unlike, the extremes of size or weight are more than four hundred millions apart. In no single family of diptera are the differences in size anywhere nearly so great as those between the niydaid and cecidomyid. Seldom do the differences in linear meas- urements in any one family exceed ten fold. Among other families of diptera the tipulids, asilids, and especial- ly the pantophthalmids, often furnish examples of large size, while the tabanids, syrphids and cyrtids have not a few forms of considerable size. The largest of all the Cyclorrhapha will be found among the Calypterae, while the Acalypterse are rarely much above the average in size, and many are small, or very small. Giantism in any group of animal life is a specialization, and is, in general, an indication of approaching decadence; enduringly small races are never the descendants of giants, for decrease in size means lessened vitality and incipient extinction. No strong or dominant group of flies, like the Tachinidse, Dolichopodidae, Syrphidse, or 3 i8 NORTH AMERICAN DIPTKRA. Bombyliidse, has ever had in the past a larger average bodily size than is found among their living representa- tives. On the other hand, those families composed to- day chiefly of large forms are ones already past their prime. These conclusions seem established for the larger forms of life, and I believe that they are in the main also applicable to insects. Many curious resemblances of external form are ob- servable among diptera belonging to widely different fami- lies and of remote relationships. Some of these, perhaps many, have a protective value, in flies of like habits; or they may have been the results of like environmental conditions. Ceria. Ceriomydas. Conops. Fig. 3. Examples of mimetic resemblances in flies. Ceria (Syrphidse); Ceriomydas (Mydaidse); Conops (Conopidse) . Slightly reduced. In figure 3 are given photographs of three wasp-like flies of very different families and of considerable size, all of them associated in the same fauna, and curious^'- HABITS. 19 resembling each other; several others equally striking might have been associated in the same group. The habits of flies are very diverse. Many are prop- erly spoken of as flower flies — that is, insects whose sub- sistence, for the most part or entirely, is obtained from the honey or pollen of flowers, and the sweetened sap of plants. Among these are many which are swift in flight, spending most of their time during sunny hours upon the wing or resting lightly upon leaves and flowers ; they all love the warmest sunshine. Some mature flies feed upon ordure or decaying material of whatever nature it may be. Many others, including whole families like the Asilidse, Dolichopodidse and Empididse, find their subsistence in the juices of other insects, and are often predaceous in the highest degree. Others, like the female mosquitoes, blackflies and horseflies, are bloodsucking in habit, though not exclusively so, and are often very annoying to man and other warm-blooded animals. The whole group of Pupipara, with the exception of the Brau- lidse, are of this kind, living parasitically upon and suck- ing the blood from mammals and birds. In the previous edition of this work I expressed the opinion that, upon the whole, the order of diptera is beneficial to man's econ- omy, since so many of its members, whether in the larval or adult conditions, are either useful scavengers, destroy- ing that which otherwise might cause distress, or prey upon other and injurious insects. Since the publication of that edition, however, the many marvelous and import- ant discoveries of the parasitic habits of certain ver}^ small protozoans which find their intermediary hosts in certain flies, by whose instrumentality they are trans- mitted to man and some of his most valued domestic ani- mals, will require the complete reversal of that opinion. Yellow fever, malaria, and filariasis, transmitted in the saliva of mosquitoes, and the fatal 'sleeping sickness' 20 NORTH AMKRICAN DIPTERA. (trypanosomiasis), likewise resulting from the predatory bites of the tsetze ^y, are among the most virulent or widespread diseases of mankind. Perhaps we may justly say that the order, so far as man is concerned, is the most pestilential of all animal life. In the larval condition the habits of flies are even more diverse than are those of the adult insects. Brief refer- ences to the larval habits will be found in the discussion of the families. Suffice it here to say that the larvae or 'maggots' of diptera are, for the most part, vegetable feeders, but not a few feed upon living or decaying ani- mal matter; and many are parasitic within the bodies of other insects, whether larvae or adults, snails, reptiles, birds and mammals, and possibly also amphibians and fishes. MORPHOLOGY OF DIPTERA. In the following pages I endeavor to give such defini- tions and descriptions of the mature insect as will enable the student to understand and appreciate, not only the present work, but all other systematic works upon dip- tera. I have not thought it desirable to consider at length many interesting subjects connected with them, such as their internal anatomy, embryology, larval habits, etc., as being rather apart from the chief object of the work — an introduction or aid to the study of S3^stematic dipter- ology. HEAD. The head in diptera is very variable in shape, reaching its most reniarkable development in the Diopsidse and Nycteribiidse. It is frequently more or less spherical, but usually the posterior surface or occiput is flattened or concave, giving a more hemispherical appearance. The face is rarel}^ produced into an elongated rostrum or snout, and the front part ma}^ be produced into a con- ical prominence. . Its relative size is also variable, some- HEAD. 2 1 times distinctly wider than the thorax, at other times small. In the Nycteribiidae it may be folded back into a groove on the dorsum of the thorax, but with these ex- ceptions, it is always attached to the thorax by a freely movable neck. The taxonomic characters furnished by the head are second only in importance to those of the wings. Eyes. The large compound eyes a're present in all dip- tera, save some Pupipara. In the majority of males, especially of the Orthorrhapha, they are contiguous on the upper side of the head, between the insertion of the antennae and the hind margin, for a longer or shorter distance; insects having such contiguous eyes are called holoptic (Osten Sacken). In many males, however (all the Acalypterse and several families of the Orthorrhapha, as well as numerous genera of other families), and in all females, with but few exceptions (certain Cyrtidae, Orphephilidse, Blepharoceridse, Bombylidse, Platype- zidse, etc.), the eyes are separated more or less broadly by the front: such insects are called dichoptic ( Williston ) . Rarely the eyes may be contiguous below the antennae, or both above and below, as in certain cyrtids, etc. In not a few flies, especially those of the aerial, bristleless kinds, the upper facets of the e^^es are larger and more conspicuous than the lower ones, sometim.es separated by a distinct line, or even entirely divided. This peculiar- ity is rarely seen in the female or even in the dichoptic male, though the dichoptic Asilidae may have the anterior facets somewhat enlarged in both sexes. Those flies hav- ing such enlarged facets usually have the eyes in life brilliantly and beautifully colored with green and purple markings — markings often characteristic of the various species, and the general pattern even of the genera. Unfortunately such markings are obliterated by dessica- 22 NORTH AMERICAN DIPTKRA. tion, though they may be somewhat revived temporaril}^ by the aid of moisture. Most flies have the eyes bare, or pubescent only when seen under high magnification. Not rarely, however, the whole or part of the eyes is covered with erect short pile, a character which usually, perhaps always, finds its greatest development in the male sex. The pubescence or pilosity may be sparse or dense, short or long, and is usually, though not always, of generic importance. Ocelli. On the upper part of the front in the middle, between or a little back of the compound eyes, there are three simple, small eye lenses, present in most diptera, and called ocelli. They are by no means constant among all the genera of some families, or even among all the species of some genera. They are usually situated in the form of a triangle with the apex in front ; sometimes they are located in a nearly straight line transversely; or, the middle one may be rarely absent, and the other two situated, one on each side, near the compound eyes. Front. The space between the eyes in all dichoptic flies, limited by the upper margin of the head and the line drawn through the root of the antennse, is called the front. It may be wide or narrow, excavated or convex, etc. Vertex. The uppermost part of the front, near the mar- gin of the occiput, which is here called the vertical margin. Vertical triangle. The triangle at the upper part of the head, between the eyes in holoptic flies. It bears the ocelli, which may be situated on a triangle indicated by grooves or depressions or colorations, called the ocellar triangle. Frontal triangle . In holoptic flies, the triangle between the eyes and the root of the antennse, the apex of which is above. Sometimes the term is applied to a triangle indicated by color or depression in the dichoptic front. Ptilinum. In the Cyclorrhapha an inflatable organ ca- HKAD. 23 pable of being thrust out through the frontal suture just above the root of the antennae, and which is used by the imago in springing off the cap to the puparium when about to extricate itself. Frontal lunule. An oval or crescentic space just above the root of the antennae in cyclorrhaphous flies, bounded by the frontal suture. Epistoma or Peristoma. The oral margin and an indefi- nite space immediately contiguous thereto; not often now used. Antennal fovea or groove. A groove or grooves in the middle of the face, as though for the lodgment of the an- tennae, bounded on the sides by ihe facial iddges. Cheeks or ^jowls'. The space back of the face and below the eyes. Orbits. The space immediately contiguous to the eyes, sometimes indicated by structural characters, at other times indefinite. It is called facial, frontal, etc., from the position. Clypeus. A part of the mouth structure, often visible below the margin of the mouth in front as a more or less viscr-shaped piece. Fig. 4. Mouthparts of female 7rt;(^rt;;2//j. After Washburn . ?;//>, maxil- lary palpus; ni, mandible; w.r, maxilla; lb, labium. 24 NORTH AMERICAN DIPTERA. MOUTH-PARTS. The mouth-parts of diptera are wholly suctorial. The}^ differ not a little in different flies, as might be supposed from their diverse habits. In some they are adapted for piercing animal or vegetable substances, and are, in con- sequence, firmer and more slender; in others, and by far the greater number, they are short and soft, with a thick- ened extremity used for the attrition of small particles of solid substances. Grains of pollen have been observed in the digestive organs of the Syrphid^ and other flower flies, but, as a rule, fluids only serve as food. Many have the proboscis wholly retractile into the oral cavity, and furnished with one or even two hinges, by which when at rest it may be folded up. In others the proboscis is not retractile, and projects either in front, or downward or backward, beneath the body. While it is usually short, it may be much longer than the body. Finally, a few species have the mouth-parts vestigial and take no nour- ishment in the adult state. The more commonly accepted homologies of the mouth- parts are as follows: labium, maxillae, maxillary palpi, mandibles, hypopharynx, and labrum or labrum-epiphar- ynx. The labial palpi are thought to be wholly wanting,* or represented by the labella. The labium is always present, more or less fleshy and provided with muscles. It is grooved or channeled on the upper side to receive the other parts, with the exception of the maxillary palpi, which are free. This sheath is often nearly complete, the thin margins touching each other above. At its tip are the pair of joints of variable size called the 'lips' or labella. The maxilla and mandibles are sometimes *This has very recently been contested by Wesche, who asserts that either the labial or maxillary palpi may be present and functional; but no cases are known of both pairs being functionally present. I am inclined to be skeptical. MOUTH-PARTS. 25 absent, the mandibles most frequently; when present they are always slender and firm. The hypopharynx is unpaired and slender, grooved on the upper side and sometimes converted into a nearly complete tube. The labrum, also unpaired, is usually elongate and grooved on the under side, forming by apposition with the hypo- pharynx a complete tube. The mandibles are frequently absent ; in fact I do not know of their occurrence in any flies with a simple third antennal joint, and they maybe absent in the male when present in the female, as in the Tabanidse. They are always piercing organs, thin, firm, chitinous and usually slender. The two maxillae, like- wise piercing organs, find their highest development in such predaceous flies as the Asilidse. Like the mandi- bles they are chitinous and slender. In some they are more or less flattened, and may have curiously shaped projections at the tip; usually they are bristle-like. They lie with the maxillae within the sheath of the labi- um, at either side of the labrum and hypopharynx. In some cases the labrum is short, and serves only as a cov- er for the proximal part of the hypopharynx, but usually it is as long as or longer than the hypopharynx and has a simple groove on the under side. The hypopharynx is always present in flies in which the mouth-parts are functional. It is, more often, a slender, firm organ, grooved upon the upper side, which by apposition with the labrum forms a distinct tube. In some, however, it may form an almost complete tube in itself. Leaving out of account the degraded, but highly spe- cialized Pupipara, the labium is always a sheath for all the other organs except the palpi, but is separable at the will of the insect. It is not used in piercing ; it is either bent backward in the middle, as in the mosquito, or the piercing parts are thrust out at the extremity as in most of the predaceous flies. To facilitate this protrusion of 4 26 NORTH AMERICAN DIPTERA. the piercing parts, the proximal portion is more or less membranous and retractile ; or, the inner organs may be capable of elongation, being coiled up in some cases, as in Pangoyiia, within the pharyngeal cavity. The pair of organs at the extremity, the lips or labella, are very va- riable in shape, position and function. In the mosquito, for instance, they serve merely as a pair of fingers to guide the piercing parts. In many of the flower-flies with long proboscis, they are small, oval, divaricable organs, that seem to be chiefly sense organs, as they are usually provided with hairs inserted in small, semi-translucent spots on the outer sides and margins. In the greater number of flies, however, the labella are of considerable size, and are provided with radiating ridges on the inner, opposable sides. These pseudotracheae, as they are call- ed, serve as means of attrition, by which the insects rub off particles of food from firm substances. Sometimes the labella are long and slender and folded back under the labium when at rest. In the Asilidse and some others, they are rigid and horny. Perhaps the most important of all the mouth-parts, from the systematic stand point, are the maxillary palpi. They are inserted at the inferior basal part of the pro- boscis, on a thin plate which bears the maxillae, and are always extricated. Their study has been much neg- lected, and doubtless thorough comparative researches will reveal not a few characters of value in classification. They are variously described as being composed of from one to five joints.* There are never more than four articu- lated joints, the basal joint being merely a process of the plate bearing the maxillae. The tendency in diptera is toward their entire loss, and in the more highly special- ized families there is never more than one joint. They ^Theobald says some Culicidae have six joints, but his statement needs confirmation. . antenn.ie:. 27 may be reduced to the merest vestiges even in flies which are mere or less predaceous in habit and which have the mouth-parts, with the exception of the mandibles, other- wise well developed ; they may indeed be absent or pres- ent in otherwise closely related genera of flies. They are seldom much elongated, save among some of the Nemo- cera. ANTENNA. Fig. 5. Antennae, i, Tipnlidae {Polyinera, female); 2, Tipiilidse {R/npidia, male); 3, Culicidse {Aedes, male); 4, Tabanidae {Stibaso- iua)\ 5, Empididse [Drapetis); 6, Syrphidae {Volucella)\ 7, Tachinidae {(jonia). No other organs furnish so many or so important char- acters in the classification of Diptera as do the antennae, or feelers as they are sometimes called. The number, shape and arrangement of the joints or segments offer not only the best of specific characters in nearly all cases, but also not rarely generic, family and even subordinal characters. Only in very exceptional instances is the number less than three, and it is probable that, even 28 NORTH AMERICAN DIPTKRA. in those, there is only a partial atrophy of the basal joint. Some Cecidomyidse and Leptidse ( Rhachicerus ) have as many as twenty-eight distinct joints, and it has been said there are as many as thirty-nine in some Cecidomyidae (Cerodoziaf), but I can find no certain evidence support- ing such a statement. Through all the Cyclorrhapha the number three, or very rarely less, is constant. In the nematocerous Orthorrhapha the number is usually from eight to sixteen, though in rare cases there m.ay be as few as six. In such antennae the first two joints are called the scape, and they are always more or less differ- entiated from the remaining segments which compose the flagellum. When the antennae are long, or more or less filiform, the joints of the flagellum often bear whorls or verticils of hairs, especially in the males, and these hairs are sometimes of very peculiar structure, sometimes loop- ed; in such antennae, also, the joints may have a long and abundant plumosity. The scape in all flies usually bears bristles or bristle- like hairs; the joints of the flagellum seldom. Upon the structure of the antennae alone, however, it is difficult, if not impossible, to distinguish any of the larger groups of diptera, since those with long and multiarticulate antennae merge very gradually into forms with shorter antennae and fewer joints. Or, the separate joints of the flagel- lum may be fused so closely as to be distinguishable with difficulty, so that the third joint, or the basal part of the flagellum, may appear to be of a simple, undiffer- entiated structure, though upon closer examination found to be composed of distinct segments or annuli; in such cases the term complex is applied to the apparent joint. This peculiar structure will be readily understood by the examination of the antennae of a common horsefly (fig. 5, 4), where the enlarged third joint is observed to be composed of a large basal piece and a terminal portion ANTENNA. 29 of four closely united segments. By the comparison of a horsefly's antennae with that of a Bibio and that of a mos- quito it will be easily understood that the complex third joint is merely the closer fusion of the real joints of the flagellum, though I know of no instance of a complex joint having more than eight segments. Nor is the horse- fly's so-called third antennal joint homologous with that of the housefly, but rather with the joint and the 'arista' combined. Either the complex or the simple third joint may terminate in a more or less slender, and more or less freely differentiated portion called the style, or in a bris- tle-like, elongated portion, called an arista. It is ver}^ evident, however, that the st5de or arista represents merely attenuated distal joints of the flagellum, since a close examination of them will invariably, or almost in- variably, disclose from two to five segments (fig. 5, 7), though some may be very small or almost completely atrophied. The arista therefore as might be supposed, is not sharply distinguishable from a slender style; in- deed the arista always, or almost always, has its basal portion thickened more or less, in some cases so much so as to form a real though short style provided with a long bristly extremity; and the style is often provided with a short bristly end. An examination of the antennae of the Leptidae and Stratiomyidse, figured further on, will make these statements clear. The arista or style is of course not at all apparent in the Nemocera, since the antennal structure is here generalized, and it maybe entirely want- ing among the Brachycera, either because the distal flagellar joints have not become at all differentiated, as may be observed in Xylophagus of the Leptidae, or because there has been an actual atrophy of the distal part of the antennae ; but the cases are rare where some of the flag- ellar joints beyond the basal one are not observable in flies, albeit very rudimentary. Whenever the style or 30 NORTH AMERICAN DIPTKRA. arista is composed of numerous segments, the basal piece of the complex third joint has necessarily fewer segments, since both together never have more than eight. The style, as the term is usually applied, is always terminal; while the arista may be either terminal or dorsal, usually the latter, and it may even be inserted close to the base of the third joint. It is also apparent here, and this is the rule among the Cyclorrhapha, that the basal position is in reality due to the greater development of the under side of the joint, b}- which the width has greatly exceeded the length. The st3de is only rarely present in the Cy- clorrhapha ( Ceria, Conops) , and in but few known instances is the arista aborted in this suborder. Fis^. 6. Talarocera nio;ripennis, head of male from in front, much enlaro"ed. The first two antennal joints, that is the scape, are, as has been said, usually provided with hairs or bristles, THORAX. 31 but the}^ rarely take on an extraordinary development. One or the other or both maybe greatly elongated (see fig. 19, Bombyliidae), or one or the other maybe greatly swollen (see Therevidse). The third joint, however, has in some cases assumed most marvelous shapes, as among the Stratiomyidse ( Neochau7ia), or Tachinidae ( Talarocera, figs. 6, 7, Schizotachhia^ Dichocera, etc.) Fig. 7. Talarocera nigripenriis, male and female antennse, from the side, much enlarged. Often the arista has short hairs fringing the upper and lower sides, in which cases it is called pubescent (fig. 5, 5); when the hairs are longer and more feather- like (fig. 5, 6), the arista is said to h^ plumose; or, if the hairs are fewer and stronger and confined to one side, pectinated. The pubescence or plumosity is almost always more marked on the upper side of the arista; the pecti- nation is very rarely on the under side ( Ommatius^ Asi- lidae). THORAX. The thorax is composed, as in other insects, of three parts, the pro-ihora.^, the fneso-thorsi:^ and the 77ieta- thorax, but the first and the last are so aborted as to pre- sent but few anatomical characters. The prothorax is perhaps most readily distinguishable in the nematocer- ous flies, forming a rounded collar back of the neck. The 22 NORTH AMERICAN DIPTKRA. metatliorax is not seen at all from above; the scutelluin, cut off by an impressed line, usually a semi-oval body, really belongs to the mesothorax, the dorsum of which is often called the mesonotu-in . T7'ansve7'se stcfure, an impressed line usually running straight across the mesonotum and terminating a little in front of the root of the wings. It is more or less incom- plete in the middle. Humerus or humeral callus, each of the anterior superior angles of the mesothorax, usually a more or less rounded callus. Post-alar callus, a more or less distinct, rounded swell- ing, situated between the root of the wing and the scu- tellum. Pre-alar callus, a similar, but usually less prominent, projection situated before the root of the wings on the sides of the mesonotum, just back of the outer ends of the transverse suture. Scutellar bridge, a small ridge on either side of the scu- tellum, connecting it with the mesonotum. Presutural depression, a depression, usually triangular in shape, at the outer ends of the transverse suture, near the dorsopleural suture. Supra-alar groove, a groove on the mesothorax imme- diately above the root of the wings, along the inner mar- gin of which there are, usually, characteristic bristles. Fig. 8. Pleural divisions of Syrphus. Pro, propleura. Meso, mesopleura. Sterno, sternopleura. Ptero, pteropleura. Hypo, hypopleura. Meta, metapleura. THORAX. 33 Notopleuj'-al or dorsopleural suture, the suture running from the humerus to the root of the wings, separating the mesonotum from the pleura. Stemopleural suture, the suture below the dorsopleural suture, nearly parallel with it and separating the meso- pleura from the sternopleura. Mesopleural suture, the suture running from the root of the wings downward and separating the mesopleura from the pteropleura. Mesopleura, the space situated in front of the root of the wings, between the dorsopleural and stemopleural su- tures. Pte7-ople2ira, situated below the root of the wings, back of the mesopleural suture. Sternopleura, the lower part of the pleura, below the stemopleural suture and above the front coxa. i Hypopleura, the space over the middle and hind coxae, below the metapleura. Metapleura, the 'sides of the metanotum', a more or less swollen space at the outside of the metanotum and between it and the pteropleura and hypopleura. Metanotum, the oval, arched portion below or behind the scutellum. It is frequently most easily observable in flies with a long, slender abdomen, as the Tipulidae. Halteres, balancers or poisers, rudimentary posterior wings, a slender organ with a dilated head, situated be- low each metapleura. SquamcB, TegulcB or Calyptrcs, a pair of membranous scales situated above the halteres and back of the root of the wings, one above the other. The lower one or both may be rudimentary or absent; the upper one moves with the wings and is called the antitegula by Osten Sacken. Comstock, however, objects to this use of tegula, saying that the term was first used for the cup-like scale above the root of the wing in certain hymenoptera, and should 5 34 NORTH AMERICAN DIPTKRA. be reserved for that organ; he calls them ahilcE, a term generally applied to the proximal posterior lobe of the wing. Fig. 9. Legs. I, leg of Tipulid; 2, middle leg of Peckia pr creeps, male; 3, hind foot of Mallophora scopipeda, male; 4, hind leg of Tropidia quadrata; 5, last tarsal joint of Dialysis; 6, front leg of Stegana horcE, male; 7, hind leg Rhopalomera ciliata; 8, hind leg of Calotarsa, male. LEGS. The three pairs of legs are attached to the prothorax, mesothorax and metathorax, and are called, respectively^ the front, middle and hind pairs. When the front and middle pairs are spoken of together they should be call- I.EGS. 35 ed, for the sake of exactness, the anterior legs; when the middle and hind pairs are collectively meant, the poste- rior legs. The legs are composed of five parts: Coxa, the part attaching the legs proper to the thorax. Trochanter, the short, small, ring-like portion between the femur and coxa. Femur, almost invariably the longest and stoutest por- tion of the legs, often provided with tubercles, spines or projections or sometimes greatly thickened; usually slender. Tibia, the next part succeeding the femur, and like it often with various ornamentations or projections. When it terminates in one or more distinct, short, bristly spines, it is said to be spiwred. Tarsus, the distal division of the legs, composed (ex- cept in some abnormal forms) of five joints, of which the first, that next to the tibia, is called the metatarsiis. On the terminal, or fifth joint, are the Ujigues or claws, usually two, curved, movable hook- lets on the under side of the last tarsal joint, at the base of w^hich below, are a pair of Pulvilli (fig. id), two pad-like, fleshy cushions attached to the last joint of the tarsus below the claw, usually pres- ent, but often absent among the Orthorrhapha and often much larger and better de- veloped in the male than the female. They are sometimes elongate, but are more usu- ally rounded, and provided with hairs. Between them is Fig. lo. Claws and pulvilli of the domestic fly. After Kellogg. Empodium, a median appendage on the underside of and between the claws, either in the form of a pad, like the pulvilli (fig. 9-5 ), when it is called pulvilliform, or like a bristle or spine (see Asilidae, fig. 31), sometimes 36 NORTH AMERICAN DIPTERA. it is' alone present and the pulvilli are wanting (see Bibionidse, fig. 7a). Fig. II. Male genitalia, i, Tipulidse {Diotrepha)\ 2 Tipulidee [Atarba); 3, Tipulidse (indet.); 4, Culicidae {Aedes)\ 5, Dolichopodi- dae {Dolichopiis)\ 6, Asilidee [Asilus). ABDOMEN. The abdomen is composed of a variable number of seg- ments, more or less closely fused together. The normal number for insects, nine, are rarely all visible (the Tip- ulidse are examples). They are counted from the base on the upper side. In not a few cases the first two are so closely fused together, and the first one abbreviated, that the nomenclature leaves some doubt in the mind of the student. The upper part of the abdomen may be es- pecially indicated by the word dorsum, but in general, the WINGS. 37 venter or under part is alone thus contradistinguished, The male genitalia, which in many cases are of compli- cated structure, and of much value in classification, are known collectively as the hypopygium, and this term is usually restricted to the male genitalia, though some- times used also for the female organs. The ovipositor of the female abdomen very frequently projects from the abdomen, and is sometimes extremely long; its structure may be characteristic of genera or families. The more detailed description of the parts of both these organs it is unnecessary to go into here; they may be studied in the different families, where they often find useful appli- cation in the separation of species, though rarely of s:enera. ^'^1/enL >ist SQvn auxii Fig. 12. Wing of Ta banns. WINGS. To understand the veuatio?i or iiem^ation of the wings the student may select a common large horsefly (Taban- idse). Observe near the middle of the wing directed transversely, a large, oblong, five or six sided cell, sur- rounded on all sides by other cells. This is the discal cell and is present in nearly all flies. Somewhere on the vein (fourth longitudinal) ^ that bounds this cell in front, will be seen a short connecting vein, directed anteriorly. 38 NORTH AMERICAN DIPTERA. the anterior, small or middle cross-vein (b), which is very constant in flies, and affords in most cases, a key to the venation, no matter how intricate. It connects with the third longitudinal vein in front (in a few cases the sec- ond longitudinal vein); the cell behind it is the discal, in front, between the second and third longitudinal veins, ih^ first submarghial ; on the outer side X.'ho: first posterior; on the inner side the first basal. Just back of the first basal cell and separated from it by the fourth longitud- inal vein, is the second basal cell; back of the second basal and separated by the fifth longitudinal vein, is the third basal or a?ial cell. Back of the anal cell and including the free posterior proximal portion of the wing is the ax- illary cell. In the horsefly the anal cell is seen to run back obliquely to near the posterior margin of the wing, where it terminates acutely, that is, the anal cell is closed near the border of the wing ; should the two veins that close it run separately into the margin of the wing, then the cell is said to be open. Counting from the third longi- tudinal vein (posterior branch) backward along the pos- terior border of the wing, to the vein that closes the anal cell outwardly, the student will count five different cells, the first of which, as already said, borders on the first basal cell, the second and third on the discal cell, the fourth on the discal and second basal cell, and the fifth on the second basal and anal cells; these cells are called \,\i^ posterior cells, and are numbered from before back; t\i^ first is bounded by the third and fourth longitudinal and the anterior cross-vein; the second posterior by the anterior branch of the fourth vein in front, its posterior branch internally and behind, often superfluously called the anterior intercalary vein; the third posterior cell is bounded in front by the posterior branch of the fourth vein, internally hy ihe poste7^ior cross vein id), posteriorly by the anterior branch of the fifth vein; the fourth posterior WINGS. 39 cell is bounded in front and internally bythe anterior branch of the fifth vein, bordering the discal and basal cells, posteriorly by the posterior branch of the fifth, often also superfluously called the posterior intercalary vein ; this cell in other flies often borders on the discal cell alone internally; \yv^ fifth posterior cell is bounded in front by the posterior branch of the fifth vein, internally by the petiole of the fifth vein, posteriorly or internally hy t\i^ posterior basal cross-veiJi. There is much doubt as to whether this latter is really a cross-vein in the more evident meaning of the word, or whether it really repre- sents the primary branch of the fifth vein, since in many flies this is the only termination of the vein, the anterior branches being wholly wanting. The short vein which separates the discal cell from the second basal cell is often called the a?iterior basal cioss-veiii; sometimes the discal cross-vein, which would be the better term, were it not to be confused with the posterior cross-vein itself. Follow- ing the third longitudinal vein outwardly it will be found to give off an anterior branch, which runs forward to ter- minate in the anterior marginal vein of the wing, the costa; the cell included in this fork, between the branch and the vein itself is called the second submarginal cell, and this name should always be restricted to the cell so bounded, though usually the cell enclosed between the branches of the second longitudinal vein in the Culicidae, Tipulidse, etc., receives this name. The second longi- tudinal vein borders the first submarginal cell in front and terminates in the costa, as the encompassing vein of the wing is called; in a relatively few flies this vein also gives off a branch in front, dividing the ma^'girial cell just as the submarginal cell is divided in Tabanus. Be- tween the first longitudinal vein, which has a similar course to that of the second longitudinal, though shorter, and the vein in front of it, between it and the costal bor- 40 NORTH AMERICAN DIPTKRA. der, and called the auxiliary vein, is the subcostal cell; between the auxiliary vein and the costal border itself is the costal cell. Finally, near the root of the wing, a short, but very constant cross-vein connecting the auxiliary vein with the costa is the humeral cross-veiti (a). The above is the nomenclature of the wing now having almost universal vogue among descriptive entomologists, a S3^stem which, with minor modifications, has been used almost from the beginning of descriptive dipterology. It has no especial superiority over other systems to com- mend it, nor has it any striking disadvantages to con- ^Suhcostctl. Fig. 13. Wing of Pang07iia. Schiner's nomenclature. I, costal cell; 2, mediastinal cell; 3, subcostal cell; 4, 5, cubital cells; 6, 7, 8, 9, II, first-fifth posterior cells; 12, discoidal cell; 13, 14, 15, first-third basal cells; 16, axillary cell. demn it; and long usage has apparently fixed it. An- other system in vogue at the present time among a few dipterological authorities is that used by Schiner in his later writings, and, which, could it displace the older system, would have much to commend it. It will be readily understood by the comparison of the two figures given. The only confusion it makes with the older system is in the use of mediastinal cell for subcostal and subcostal for marginal, and this confusion is actually apparent in the writings of some authors, of whom Ver- rall is an example. WINGS. 41 Fig. 14. Wing of Silvius. Comstock-Needham nomenclature. A third system is that proposed by Comstock and Needham about ten 3^ears ago, but which has found practically no acceptance among dipterologists, with the exception of one or two American waiters. There is much to be said in favor of a universal system of nomen- clature among entomologists, a consummation devoutly to be wished. The present work, however, is no place for propagandism, and the common nomenclature has been everyv/here employed in the following pages. The individual writer may do as he chooses in the use of either of the three systems, though he would do well to remember that ephemeral writings or briefer communi- cations will suffer by the use of any except the standard; only thorough monographic studies with abundant illus- trations will do much toward commanding the acceptance of either of the less used nomenclatures. I give below in tabular form the synonymy of the three systems for the Tabanus wing: Auxiliary vein . First longitudinal . Second longitudinal Third longitudinal . Fourth longitudinal Fifth longitudinal . II Subcostal nil Radial i . III3 Radial 3 . 1114,5 Radial 4, 5 Vi,2 Cubital I, 2 V3 Cubital 3 . Mediastinal vSubcostal Radial Cubital Discoidal Postical 42 NORTH AMERICAN DIPTERA. It. Fig- 15. ScR. /?5+^. Rhyphus (Rhyphidae) Fig. 16. ;p Enlonchus fe (Cyrtidae) , Fig. 17. Pantarbes (Bombyliidae) Fig. 18. Con ops (Conopidae). Fig. 19. ■^.♦. Scenopinus (Scenopinidae) 4 + S Fig. 20. Rhaniphojnyta (Empididae.) /»/,+«- cholabis coinplexa; 31, Rhamphidia albitarsis; 32, Atarba pleuralis. The name of 'daddy-long-legs' is tlie one usually applied to members of this family in England, but in America this term is generally used to designate the Phalangidae or harvest spiders. The name 'crane-flies' is preferable. Commonly they are harmless, but some of the species in the larval state are very destructive, feeding upon the tender rootlets of grass and grain, and causing the plants over large surfaces to wither and die. There are about twelve hundred species known. Trijnicra pilipes; 9, Liinnophila quadrata; 10, Gnophofnyia tristis- sitna; 11. Rhypholophus riibellus; 12, Bittaconiorpha clavipes; 13, Anisoniera neglecta; 14, Rhaphidolabis tenuipes; 15, Orimarga al- pina; 16, Dicranomyia heretica; 17, Dicranotnyia longipennis; 18, Toxorhina magna; 19, Liinnophila areolata; 20, Erioptera, sp. ; 21, Helobia punctipennis; 11^ Antocha opalizans. After Osten Sacken. 86 NORTH AMERICAN DIPTKRA. In this family are placed several wingless forms, or those with the wings more or less rudimentary. One of the former is Chionea, the species of which are found on snow, often in the coldest weather. The family Tipulidae is easily divided into three sub- families, which I prefer to call the Ptychopterinse, I^im- nobiinae and Tipulinse, and which correspond precisely with the Ptychopterina, Tipulidae brevipalpi and Tipu- lidae longipalpi of Osten Sacken. The following table is chiefly based upon that of Osten Sacken in his monograph, which will be indispensable to the student. The nomenclature of the venation is that of Osten Sacken. TABI.K OF GKNERA. 1. Seventh longitudinal vein present, that is there are two longitud- inal veins between the fifth vein and the posterior margin of the wing. ........... 2 Seventh longitudinal vein absent; no distinct V-shaped suture on meson otuni. ...... Ptychopterinse. 2. Last joint of the palpi shorter or not much longer than the two pre- ceding together; the auxiliary vein usually ends in the costa and is connected with the first longitudinal vein by a distinct cross- vein; antennae six to sixteen jointed, rarely more. LimnobiinsB I^ast joint of the palpi whiplash-like, much longer than the three preceding together; antennae rarely with more than thirteen joints; the auxiliary vein ends in the first longitudinal vein by an abrupt curvatvire at the tip, not connected with the first vein by a cross- vein. Tipulinae. I^IMNOBIIN^. 1. Wingless, spider-like in appearance. . . . Chionea. Winged. ........... 2 2. A single submarginal cell present. ...... 3 Two submarginal cells present (one in Goniomyia nianca.) . 5 3. Antennae 14-jointed. Limnobiini. Antennae i6-jointed. . . 4 TIPUWD^. 87 4. Tibise with spurs at the tip; the first longitudinal vein usually ends in the second Oylindrotomini. Tibise without spurs; the first vein ends in the costa. Antochini. 5. Tibise without spurs at the tip. .... Eriopterini. Tibise with spurs at the tip. . . . . . . .6 6. The subcostal cross-vein is beyond the origin of the second longi- tudinal vein. ......... 7 The subcostal cross-vein is before the origin of the second longi- tudinal vein. Amalopini^ 7. Antennas composed of sixteen joints. . . Limnophilini. Antennae composed of from six to ten joints, often much elongated. Anisomerini. I^IMNOBIINI. 1. Proboscis longer than the head and thorax together (29). Geranomyia. Proboscis shorter than the head and thorax together. . . 2 2. Antennae pectinate or subpectinate, at least, in the male (25, p. 80. 3) Rhipidia. Antennae not pectinate. . . . . . . . • . 3 3. A supernumerary cross-vein between the sixth and seventh veins. Discobola. No cross-vein connecting the sixth and seventh veins. . . 4 4. Tip of the auxiliary vein usually opposite, or before, or only a short distance beyond the origin of the second vein; marginal cross- vein always at the tip of the first longitudinal vein; legs slender. Dicranomyia. Tip of the auxiliary vein usually far beyond the origin of the second vein; marginal cross-vein sometimes at the tip but often some distance before the tip of the first vein; legs comparatively stout. Limnobia. ANTOCHINI. 1. Rostrum at least as long as the head, sometimes very long; no mar- ginal cross-vein. ......... 2 Rostrum shorter than the head. ...... 4 2. Wings without submarginal cell (18). . . . Toxorhina. Wings with submarginal cell 3 3. Rostrum not much longer than the head (31). Rhamphidia. Rostrum the length of the body. . . . Blephantomyia. 88 NORTH AMERICAN DIPTERA. 4. Discal cell open. , • • • 5 Discal cell closed. . . . . . . . . . 7 5. Second basal cell considerably shorter than the first. . . 6 Second basal cell of about the same length as the first (23) . Elliptera. 6. Three posterior cells; the great cross-vein more proximal than the origin of the second vein (24). . . . Diotrepha. Four posterior cells; the great cross-vein more distant than the origin of the second vein, .... Orimarga. 7. No marginal cross-vein whatever (32, p. 80, 2) . . . Atarba. Marginal cross-vein present. ...... 8 8. The first longitudinal vein ends in the costa nearly opposite the inner end of the submarginal cell. ..... 9 The first vein ends in the costa far beyond the inner end of the submarginal cell. Dicranoptycha. 9. Submarginal cell as long or but little longer than the first posterior cell (30) Teucholabis. Submarginal cell much longer than the first posterior cell (22). Antocha. KRIOPTKRINI. 1. Five posterior cells; male antennae not peculiar. . Cladura. Five posterior cells; joints of the male flagellum binodose, form- ing apparently twenty-eight joints in the antennae (25 also fig. 5,1, page 27, 9) Polymera. Four posterior cells. . . . . . . .' . 2 2. The inner marginal cell has almost the shape of an equilateral tri- angle (6) Cryptolabis. Inner marginal cell of the usual shape. . . . . 3 3. Wings conspicuously hairy on the whole surface or along the veins. ........... 4 Wings not conspicuously hairy, veins bare or nearly so. . 7 4. Antennal joints subreniform and nodose; eyes nearly contiguous above and below. Sigmatomera. Species not having the foregoing characters. ... 5 5. Wings hairy on the whole surface (11). . Rhypholophus. Wings hairy along the veins only. ...... 6 6. Second submarginal cell longer than the first (20) . Erioptera, First submarginal cell longer than the second. Molophilus. TIPUUD^. 89 7. First submarginal cell short, not more than half the length of the second. .......... 8 First submarginal cell more than half the length of the second. 11 8. Marginal cross-vein present. . . . . . . • » 9 Marginal cross-vein absent (7) Goniomyia. 9. Second submarginal cell in contact with the discal cell, the ante- rior cross-vein obsolete. . . . . . . .10 Anterior cross-vein present, the first posterior cell intervening be- tween the submarginal and the discal cells. . Empeda. 10. Seventh longitudinal vein very short; no empodia (26) . Mongoma. Seventh longitudinal vein not unusually short; empodia present. Paratropesa. IT. Seventh longitudinal vein conspicuously bisinuate (21). Helobia. Seventh longitudinal vein straight. . . . . . 12 12. lycngth of the auxiliary vein beyond the cross- vein at least twice that of the posterior or great cross-vein (8) . . Triniicra. The cross-vein situated near the end of the auxiliary vein (10) . Gnophomyia. I,IMNOPHII,INI. 1. Discal cell open; antennae apparently 28-jointed in the ^ (28). Polmera. Discal cell closed. . . . . . . . . . 2 2. Marginal cross-vein wanting. .... Phyllolabis. Marginal cross-vein present. ....... 3 3. Wings pubescent, . . . . . . Ulomorpha. Wings bare. '4 4. Seventh vein very short, abruptly incurved toward the anal angle (5) Trichocera. Seventh vein not unusual. .5 5. A supernumerary cross-vein between the auxiliary vein and the costa (p. 80, 5) Epiphragma. No such supernumerary cross-vein (1, 9, 19) *. Limnophila. * A wingless form has recently been referred to this genus, with doubt, by Mr. Coquillett. go NORTH AMERICAN DIPTERA. ANISOMERINI. 1. Three posterior cells; two submarginal cells (13) . Anisomera, Four or five posterior cells; antennae of the $ sometimes much elongated. .......... 2 2. The stigma occupies nearly the whole space between the tip of the auxiliary vein and the marginal cross-vein, . Eriocera. The stigma occupies but a small portion of the space between the tip of the auxiliary vein and marginal cross-vein, Penthoptera, AMAI^OPINI. 1. Antennae composed of thirteen joints ..... 2 Antennae composed of sixteen or seventeen joints, . . 5 2. Two cross-veins between the first longitudinal vein and the anterior branch of the second vein, ..,,.., 3 Only one cross-vein between these veins. , . , , 4 3. Front with a gibbosity behind the antennae (2), . Dicranota, Front without gibbosity Polyangaeus. 4. Five posterior cells; both branches of the fourth vein furcate (14) . Rhaphidolabis . Four posterior cells; the posterior branch furcate, Plectromyia, 5. Four posterior cells; wings pubescent. .... Ula, Five posterior cells; wings bare, ...... 6 6. Anterior cross-vein nearly at right angles with the longitudinal axis of the wing. ,,.....,, 7 Anterior cross-vein at a very oblique angle with the longitudinal axis of the wing, and parallel with the posterior cross-vein (p. 80, 1) Pedicia. 7. Rostrum much longer than the head. . . . Ornithodes. Rostrum shorter than the head (4) . . . . Amalopis CYI.INDROTOMINI. 1, Five posterior cells; colors yellow and black. Cylindrotoma, Four posterior cells, ......... 2 2, Antennal joints .subcylindrical, elongated. .... 3 Antennal joints subglobular; head and thorax conspicuously punct- ulate Triogma. 3, Colors yellow and black. ...... Liogma. Colors brownish and grayish, .... Phalacrocera. TIPULID^. gi PTYCHOFTKRIN^. 1. First subniarginal cell much shorter than the second. Idioplasta. First subniarginal cell much longer than the second. . . 2 2. Three posterior cells (12) ..... Bittacomorpha. Four posterior cells. . . . . . Ptychoptera. TIPULIN^. 1. Legs long and slender, especially the tarsi; anterior branch of the second vein absent, obsolete or perpendicular, the rhomboid cell more or less square. ....... 2 Legs not unusuallj^ slender, anterior branch of second vein present and oblique. ......... 5 2. Antennae thirteen-jointed; male forceps complex. Dolichopeza. Antennae with less than thirteen joints; male forceps small, simple. 3 3. Fifth posterior cell not in contact with discal cell. Megistocera. Fifth posterior cell in contact with discal cell. ... 4 4. Head on a neck-like prolongation of the thorax; seventh vein short, running into the anal angle. . . . Brachypremna. Head more closely applied to the thorax; seventh vein terminates in the margin at some distance from the anal angle. Tanyprema 5. Antennae of $ pectinate or sub-pectinate. .... 6 Antennae not pectinate. ........ 7 6. Ovipositor of 9 long) sword-like. . . . . Xiphura. , Ovipositor of 9 lo"g but not sword-like (p. 80, 4) . Ctenophora. 7. Three posterior veins arising from the discal cell, the two anterior sometimes arising together but the petiole always short (p. 80, 7) Pachyrrhina. Two posterior veins arise from the discal cell, the anterior one fur- cate, petiole always of considerable length. ... 8 8. Antennae serrate; northern species. . . . Stygeropis. Antennae not serrate below. ....... 9 9. Marginal vein wanting, but one marginal cell; antennal joints short with minute bristles. ...... Holorusia. Two marginal cells. ......... 10 10. Abdomen slender, very long; antennae composed of twelve joints. Longuria. Abdomen less elongate; antennae with thirteen joints (27). Tipula. II. Family PSYCHODID^. Thickly haired, minute flies, in appearance moth-like. Head small; ocelli wanting. Antennae as long as the head and thorax together, bead-like; thickly haired; composed of from twelve to sixteen joints; the two basal joints shorter and short-cylindric. Proboscis usually short ; or more or less elongated ( Ph lebotomus) and rigid; palpi incurved and hairy; composed of four joints of nearly equal length. Thorax not very convex, with- out transverse suture; scutellum rounded. Abdomen cylindrical, composed of from six to eight segments; male genitalia prominent. Legs short, densely hairy; claws small. Wings large, ovate or lanceolate in shape; when at rest lying roof-like over the abdomen ; densely covered with hair or tomentum, which also forms a fringe around their margin; the costal vein continuous about the wing; veins strong, for the most part concealed be- neath the hair ; venation formed almost wholly by longi- tudinal veins; the anterior cross-vein is short and lies near the root of the wing and is often difficult of discern- ment; the second longitudinal vein arises near the origin of the first and is furcate. Fourth vein furcate; between these two furcations there are usually two longitudinal veins, the precise homologies of which are uncertain; the front one is often supposed to be an additional furcation of the second ; or it may be a furcation of the third occur- ring before the anterior cross-vein, a peculiar structure found elsewhere in diptera only among the Tipulidae i^^Ptychopterince) . The vein just before the posterior furca- tion terminates near the tip of the wing. Fifth and sixth veins terminate in the border of the wing, as does also the seventh, which is, sometimes, very short. 92 PSYCHODID^. 93 The members of this familj^ are often very minute, rarely exceeding the length of four millimeters ; they are observed in shady places, on windows, in outhouses, or running about on leaves near streams of water, and will be readily recognized by their peculiar moth-like appear- ance ; they run about nimbly, but their flight is weak. The larvae live in rotting vegetable material, in dung, or in water; they are peculiar in having both open spira- cles and tracheal gills ; the maxillae are imperfectly de- veloped, there are eye-spots on the head, and the segments behind the head are without feet, but are provided with sucking disks, in the aquatic forms at least. Fig. 26. Psychodidse. 1, Psychoda, W\v\g\ 2, Pericoma, ^Nxng (Eaton); 3, Sycorax, wing (Eaton); 4, Trichoniyia, wing (Eaton). Tx\BLE OF GENERA. 1. Two simple longitudinal veins between the forked veins. . 2 One simple longitudinal vein between the forked veins. . 4 2. The first simple vein arises from the forked vein much beyond the anterior cross-vein {Flebotonius!) . . Phlebotomus. The first simple vein arises near anterior cross-vein. . . 3 3. The second simple vein ends at or near tip of wing (1) . Psychoda The second simple vein ends distinctly beyond tip of wing (2). Pericoma. 4. The seventh longitudinal vein (the most posterior one) not much shorter than the sixth (4) Trichomyia. The seventh longitudinal vein very short (3) . . Sycorax. II III. Family DIXID^. Fig. 27. Dixa species; enlarged. After Kellogg. Rather small, slender, nearly bare species. Proboscis somewhat projecting; palpi four-jointed; antennae long, the basal joints thick, those of the flagellum hair-like, and the joints indistinctly distinguishable. Eyes round, dichoptic; no ocelli. Thorax strongly convex, without transverse suture ; scutellum transverse ; metanotum arched. Abdomen long and slender, composed of seven or eight segments, thickened posteriorly in the male, pointed in the female. Legs long and slender; coxae somewhat elongated; tibiae without terminal spurs. Wings comparatively large; auxiliary vein present, ter- minating in the costa before the middle of the wing; the second vein arises from the first near the middle of the wing and appears to be the beginning of the third vein, which continues its direction while the second arches suddenly forward at or near the anterior cross-vein and is furcate; fourth vein furcate; four posterior cells pres- 94 DIXID.^. 95 ent; the two basal cells complete; the anterior cross- vein is near the beginning of the third vein, where the second vein curves forward. The family Dixidse comprises about a score of known species belonging to the single genus Dixa. The genus has been placed among the Tipulidse and Culicidae, but is provisionally isolated into a separate family. The larvae are aquatic, living in ponds or slowly running water; they resemble those of the mosquitoes. The flies are found in bushy, moist places about forests, and have been observed by Winnertz dancing in the air in swarms. IV. Family CUIvICID^. Slender flies, for the most part characterized by the projecting, slender proboscis and the thickly plumose antennae of the males. Head small, subspherical; eyes reniform; ocelli wanting. Antennae slender, elongate, composed of fourteen or fifteen joints; first joint globose, the following elongated, nearly or quite cylindrical and beset with whorls of hair, forming, with but few excep- tions, in the male a dense plumosity, but shorter and less conspicuous in the female ; in the male the last two joints almost always more elongated and nearly bare. Thorax ovate, arched, but not projecting over the head, without transverse suture; scutellum narrow, uni- or trilobate; metanotum usually arched. Abdomen long and narrow, somewhat flattened, composed of eight or nine segments; male genitalia prominent; ovipositor short. Legs long and slender; coxse not elongate ; tarsi long; claws often denticulate, especially in the males. Fig. 28. Venation of Culex. Wings long and narrow, while at rest lying flat over the abdomen; with six fully developed longitudinal veins reaching the costal margin; the hind margin is 96 CULICID^. oy fringed with hair or scales and the costal vein encom- passes the wing ; auxiliary vein distinct, reaching to or beyond the middle of the wing; second, fourth and fifth longitudinal veins furcate; third vein simple, arising from the second angularly beyond the middle of the wing; anterior cross-vein situated near or even proximal of the origin of the third vein. Two basal cells present, elon- gate, the anal cell wide open. Veins of the wings cloth- ed with scales. The foregoing description and figure of the wing do not wholly agree with those of other writers. It is evi- dent, unless we change the nomenclature of the brachy- cerous flies, that the furcation of the second vein does not form a submarginal cell; the so-called 'first submar- ginal cell' is in reality the second marginal. Further- more, it is as clearly apparent that the so-called 'poste- rior cross-vein' is not the vein of that name among the brachycerous and cyclorrhaphous flies, but is, rather, the 'discal' or 'discoidal cross-vein', or the 'anterior basal cross-vein'; or, at least, a cross-vein which has not yet received a definite name. Since the last edition of this work was published, in 1896, the marvelous discoveries in the life histories of the Culicidae, and their agency in the transfer of disease, have given to the family an importance in man's econo- my second to that of no other group of insects. Indeed, one may say with entire truth that these little flies, or 'gnats' as the English call them, are the most baneful and pestilential of all known insects. The microscopical parasites producing malaria, yellow fever and filariasis are now known with certainty to be transferred by the agency of certain mosquitoes from one human being to another, and it is probable, though of course not certain, that if all the germ-bearing mosquitoes could be made extinct these diseases would at least cease to trouble 98 NORTH AMERICAN DIPTKRA. Fig. 29. Mochlonyx cinctipes. Female adult; enlarged. After J. B. Smith. CUIvICID^. 99 mankind. The parasitic microorganism is a small pro- tozoan which undergoes development in the red corpus- cles of the blood, destroying them, and there seems to be no way, in general at least, in which it may be transfer- red from one person to another save by the activity oi these insects. Taken into the mosquito's stomach with the blood sucked up by the insect it there undergoes sexual regeneration, of which the newly generated germs or 'blasts', penetrating the walls of the mosquito's stom- ach, reach the salivary glands, and are thence transfer- red with the poisonous saliva emitted by the insect into the wounds made by its puncturing 'bites'. ¥• Fig. 30. Ciilex- taeniorhynchus. i, female adult ; 2, front claws of female; 3, front, 4 middle, 5, hind claws of male; all much enlarged. After J. B. Smith. lOO NORTH AMERICAN DIPTERA. Not all mosquitoes are criminals in this respect. Only certain forms of Anopheles (in its wide sense) are known to carry the germs of malaria ; while but a single species, I' I Fig. 31. Anopheles pu7ictipennis. i, female adult; 2, female pal- pus; 3, genitalia; 4, part of wing vein showing scales; 5, front, 6, middle claws of male; all much enlarged. After J. B. Smith. CULICID.^. lOI the Ciilex or Stegomyia fasciata, is so far known to cause the deadly yellow fever. But these disease-bearing spe- cies are widely distributed over the earth, accounting for the wide distribution of malaria and yellow fever. Fig. 32. Aedes fusciis. 1, female adult; 2, female palpus; 3, male palpus; 4, front, 5, middle, 6, hind claws of male; all much enlarged. After J. B. Smith. I02 NORTH AMERICAN DIPTERA. Probabh^ we shall yet learn of other mosquitoes which are culprits in these respects. This gravely important bearing of the mosquitoes in man's economy has given a tremendous impulse to their study, though not always with the most happy results so far as their taxonomy is concerned. Whereas ten or twelve years ago only about one hundred and fifty spe- cies of the family were known, we now have an accred- ited list of Culicidae of nearly or quite six hundred spe- cies, and there are probably several hundred more yet awaiting discovery. It seems a fact that the mosquitoes present but few and slight structural differences among themselves ; the many closely related forms seem to indicate a late geological crudescence. Such organisms are always difficult to classify. The wing venation has acquired much fixity, whereas the many secondar}^ sexual differences in the mouth-organs would indicate a late adaptation to blood- sucking habits. The Culicinae probably have developed from the corethrine type, which is doubtless an older type, now decidedly on the wane. Until within a few years scarcely a half dozen genera of the mosquitoes had been recognized by dipterologists, and they were based chiefly on the secondary sexual mouth characters. Within these few years, however, the numerous writers on this group of insects have proposed fully one hundred gen- era, for the most part merely subdivisions of the older genera, founded on minor characters, chiefly the shape and arrangement of the scales of the body and wings. It seems to be the consensus of opinion among other dipter- ologivSts that the use of such characters has been car- ried to an undue and even absurd extreme. Of course the first requisite in classification is that distinguishing characters shall be 'natural', that is genetic, not homo- plastic or parallel characters. When such are found it CULICID^. 103 really makes little difference how far they are carried, save that their use in one group, necessitates or stimu- lates the use of like minor characters in other groups. One cannot raise a genus of Culicidse to family rank, without raising all other genera of like degree pari passu. But I am firmly of the opinion that the scale characters are in a high degree artificial, and that their use will Fig. 33. Aedes niusiciis. i, female adult; 3, claws of female front; 6, hind claws of male; enlarged. After J. B. Smith. I04 NORTH AMERICAN DIPTERA. never be accepted by dipterologists in general. And secondary sexual characters should also be tabooed so far as possible, since they represent merely evolutional instability. The formation of so many genera from these slight characters, is, however, no 'worse than the attempt to classify and name genera and species purely from the larval stage, which has been done to a degree never be- fore attempted by scientific dipterologists. Upon the whole the characters made use of in the fol- lowing table, verbally modified from Dyar and Knab, come nearest to my own views of proper classificatory characters for the family. I am not able to test the table thoroughly, and cannot vouch for it, but I believe it to be the best that has so far appeared. The student may also consult a recent table of the genera published by D. W. Coquillett.* The habits of the immature stages of the Culicidse are so familiar to all that little need be said here regarding them. The eggs are laid by the females upon the surface of stagnant or nearly stagnant water, in groups or singly, whence the young larvae, hatching, descend into the water to form those active little creatures of the rain- barrel, commonly known as 'wigglers'. The pupal stage is less active, passed in large part near the surface of the water, hanging by the respiratory tubes. The adult in- sect emerges from the pupal skin through a rent, using its discarded shell as a temporary raft until its wings are fully extricated. The following description of the larvae of the mosqui- toes is paraphrased from Dyar and Knab: * Bull. U. S. Dept. Agric. Tech. Ser. No. ii (1906). CUIvICID^. wjum',riiniiiii"iimiiiiiiim ^ Fig. 34. Psorophora ciliata. i, female adult; 2, female palpus; 3, front; 4, hind claws of male; enlarged. After J. B. Smith. 12 io6 NORTH AMERICAN DIPTERA. Head well formed, enclosed in a chitinous covering; with compound eyes, single-jointed antennse, a group of liairs before tke oral orifice, toothed mandibles, maxillae, and single-jointed palpi. Thoracic segments consolida- ted into a transversely elliptical flattened mass ; abdomen with nine slender and moniliform segments, the eighth with a dorsal, respiratory opening, often prolonged into a chitinous tube; last segment furnished with a chitin- ous plate, and usually with four delicate anal append- ages. The body has setae in tufts or singly, usually more or less conspicuously feathered. From other aquatic nematocerous larvae, the mosquitoes are distinguished by the presence of the mouth-brush, the shape of the anal segment and the absence of abdominal feet. The larvae of Dixa and the Corethrinae are practicably indis- tinguishable from those of the Culicinae, save by minor characters.* I^'ig- 35' Culicidse. i, Megarhinus^ wing; 2, Megarhiniis, head, male; 3, Aedes, wing; 4, Hcemagogus, head, female; 5, front claws of Hcsniagogtis, male; 6, Wyeoniyia, head of female; 7, Corethra, hind tarsus. TABLE OF GENERA. Proboscis short, not adapted for piercing. . . Corethrinae. Proboscis much longer than the ^ head, firm, adapted for piercing. Mosquitoes Culicinae. *I especially commend to the student interested in this family of flies the comprehensive and richly illustrated Report upon the Mosquitoes of New Jersey (1904), by Prof. J. B. Smith, CULICID^. 107 CORKTHRIN^. 1. Hind metatarsi shorter than the following joint {Corethra^ Coquil- lett) . (fig. 29) Mochlonyx. Hind metatarsi longer than the following joint. ... 2 2. Small species; ungues simple. ....'.. 3 Large species (10 mm); ungues bifid. . . . Pelorempis. 2. Antennae verticillate {Sayomyia Coq\x\\\&\X) (7). Corethra. Antennae of male thickly clothed with long hairs; of the female with a basal and an irregular median circlet of hairs on each joint Corethrella, CULICIN^. AFTER DYAR AND KNAB. 1. Metanotum without setae (Culicini) . ..... 2 Metanotum with setae (Sabethini). ..... 15 2. vScutellum evenly rounded, not lobed. ..... 3 Scutellum distinctly trilobate. .....: 4 3. Second marginal cell longer than itspetiole (fig. 31) Anopheles. Second marginal cell less than half as long as its petiole (1, 2). Megarhinus. 4. Hind tibiae near their tip with a row of seven to twelve closely set setae. .......... 5 Hind tibiae with none to five sparsely set setae. ... 14 5. Scutellum with its median lobe elongate, collar-like, not tubercu- larly prominent, ......... 6 Scutellum with its median lobe distinctly prominent and tuber- cular. ........... 7 6. Terminal antennal joints slender, long. . . Mansonia. Terminal antennal joints short, broad. . . . Aedomyia. 7. Second joint of antennae very long, 14:1. . Deinocerites. Second joint of antennae moderately long, less than 8;i. . 8 8. Second marginal cell less than half as long as its petiole. Uranotsenia. Second marginal cell at least nearly as long as its petiole. 9 * My examination of the literature leads me to quite different con- clusions than those of Coquillett regarding the types of Corethra and Mochlofiyx. There is no call for disturbing these names so long es- tablished. io8 NORTH AMERICAN DIPTERA. 9. Head with a distinct neck, the occiput broad and exposed (fig. 34) . Psorophora. Head without distinct neck, appressed to the thorax. . 10 10. Cross-veins approximated and nearly in line with the basal sec- tion of the third vein. . . . - . Culiseta. Cross-veins not approximated, separated by at least the length of the posterior. ......... 11 11. Last segment of the female abdomen not extensile, large, trun- cate; male genitalia with the harpes slender, columnar, with bent, spined tip Tseniorhynchus. Last segment of the fetiiale abdomen extensile, slender; male genitalia with harpes broad, concavely curved. . . 12 12. Clypeus bare. ......... 13 Clypeus with dense appressed scales. . . . Stegomyia. 13. Prothoracic lobes approximated (4,5). . Haemagogus. Prothoracic lobes well separated (figs. 32, 33). . Aedes. 14. Empodia large. Lutzia. Empodia small (fig. 30) Oulex. 15. Clypeus M'ithout hairs. . . . . . . . .16 Clypeus hairy on the sides. ..... Joblotia. 16. Prothoracic lobes contiguous, densely hairy. . Sabethes. Prothoracic lobes well separated. ...... 17 17. Eyes narrowly separated by the front; proboscis rather short, swollen at tip. ......... 18 Eyes contiguous at vertex. . . . . •. . . 19 18. Hind tarsi with two claws, normal (6). . . Wyeomyia. Hind tarsi with but a single claw. . . . Limatus. 19. No erect forked scales on occiput; proboscis longer than the body. Phoniomyia. With a row of erect forked scales on occiput; proboscis not longer than the body. . . . . . . . . . 20 20. Face normal, smooth. .... Lesticocampa. Face with a conical process above the clypeus. Runchomyia. The following synonymy is given by Dyar and Knab: Anopheles Meigen: Myzotnyia Blanch., Cycloleppteron Theob: Nototricha Coq., Cellia Theob., Arribalzagia Theob., Coelodiazesis D. and K. Mansonia Blanch.: Pneiimaculex Dyar. CULICID^. 109 Taeniorhynchus Lynch: Coquillettidia Dyar. Aedes Meigen: Ochlerotatus J^ynch., Hetoronycha hynch.,Ja?Uhino- sonia Lynch, Conchyliastes Coq., Grabhatnia Theob., Howardina Theob., Culiselsa Felt, Ciilicada Felt, Ecculex Felt, Prolocu/est: Felt, Pseudoculex Y)ya.r, Gyni7iornetopa Coq., Lepidoplatys Q.oq^., Feltidia Dyar, Ceratocystia D. & K. Hsemagogus Will.: Cacomyia Coq., Stegoconops 'L,\x\.z. CulexLinn.: NeoculexTiyox, Culicella Felt, Melanoconion, Theob., Ttnolestes Coq. , Micrcsdes Coq. , Isostomyia Coq. , Mochlostyrax D.&K. Sabethes R.-D. : Sabethoides Theob. Wyeomyia Theob.: Dendroniyia T\\eoh. Liraatus Theob.: Stniondella Laveran. Joblotia Blanchard: Trichoprosopon Theob. V. Famii^y CHIRONOMID^. Gnatlike flies of slender form, seldom reaching ten mil- limeters in length; the males conspicuous for their plu- mose antennae. Head small, spheroidal, more or less concealed by a projecting, hoodlike thorax. Antennae threadlike or beadlike with not less than six nor more than fifteen joints ; in the male usually with a long dense plumosity; in the female with inconspicuous hairs and sometimes with a smaller number of joints; the first joint short and thick. Byes reniform or oval; ocelli wanting or rudimentary; proboscis short; palpi three or four- jointed; the last usually elongated. Thorax ovate, very convex, usually projecting above in front more or less over the head; without transverse suture; scutellum small, hemispherical. Abdomen usually narrow and long, composed of eight segments; hypopygium project- ing forcep-like; ovipositor very short, but little devel- oped ; legs usually slender and long ; especially the front pair; coxae of moderate length. Tarsi often much elon- gated. Wings narrow and long; bare or uniformly hairy; anterior veins stronger and darker colored than the others; auxiliary vein complete, but usually very weak and slen- der; second longitudinal vein usually wanting; third vein sometimes forked close to its origin, the upper branch often rectangular and having the appearance of a super- numerary cross-vein; fourth vein often, the fifth usually, furcate ; posterior cross-vein often wanting ; the costal vein terminates near the tip of the wing at the termina- tion of the third vein. This family comprises a large number of very delicate, often minute flies, commonly known as midges, which no CHIRONOMID^. Ill have not been much studied by entomologists ; about one thousand species are known throughout the world. They will be distinguished from the mosquitoes, which they resemble very much, by the costal vein not being continuous on the posterior side of the wing. The an- tennae are usually conspicuous, especially in the males, although agreeing in this respect with male mosquitoes. The larvae are soft-skinned, worm-like, often blood-red in color and usually aquatic, as are also the active pupae, though some live in decomposing vegetable matter, or in the earth. These midges are often seen, especially in the early spring or in the autumn, in immense swarms, dancing in the air, and have doubtless in many cases given rise to exaggerated stories of mosquitoes. Over meadows in the Rocky Mountains the writer has seen them rise at nightfall in the most incredible numbers, producing noise like that of a distant waterfall, and audi- ble for a considerable distance. While at rest they usually raise their forelegs in the air and keep them con- stantly vibrating. Aquatic larvae may be frequently met with in standing water, often extremely delicate little creatures, so transparent as to be hardly distinguishable; they have been dredged from nearly one thousand feet below the surface of Lake Superior. Most of the species are inoffensive, or actually benefi- cial as scavengers. There are some, however, belonging to the genus Ceratopogon and its allies, and known gen- erally as midges, or punkies, which have the power of sucking blood and are extremely annoying. In the White Mountains, at the seashore, along mountain streams gen- erally, and in the West Indies they are especially trouble- some. The larvae live in the flowing sap of trees, in decaying vegetation, under fallen leaves, or in water. I have included in this family, and have added to Pro- fessor Johannsen's table the diagnosis of the genus 112 NORTH AMERICAN DIPTERA. Fig. 36. Chironomidse. i, Ablabesmyia, wing; 2, Chironotnus, wing; 3 Corynoneura, wing (Johannsen); 4, Culicoides, wing; 5,/c- hannseniella, wing ; 5a, Johannseniella, antenna ; 6, Orthocladius, wing; 7, Bezzia, wing; 7a Bezzia, front leg; 7b, Bezzia, palpus; 8, Diamesa, wing (Johannsen); 9, Procladius, Tanypus, wings (Jo- hannsen); 10, Johannseniella, Palpomyia wings (Johannsen) ; 11, Sienoxenus, wing (Coquillett); 12, 13, 14, Ceratopogon (empodium of 12, omitted); T3a, Ceratopogon, antenna; 13b, Ceratopogon palpus; 15, CamptocladtMS (Wulp). CHIRONOMID^. 113 Stenoxtnus Coquillett, (fig. 11) referred by its author to a new family. Mr. Coquillett's interpretation of the neuration is clearly wrong: the fourth vein is coalescent with the third and first for a considerable distance, but all three veins are distinct distally and of the usual Chi- ronomid structure. The genus was based upon a single female specimen without antennae, so that its more exact position in the family must await further study. TABLK OF GKNKRA. BY PROF. O. A. JOHANNSEJN. 1. First, third and fourth longitudinal veins coalescent for the larger part of the distance between the humeral cross-vein and the posterior branch of the fourth; third vein long, not connected with the first vein by a cross-vein; front concave (11). Stenoxenus. Fourth vein not at all coalescent with the first. ... 2 2. Wings short, strap-like, thickened, and without distinct venation. Eretmoptera. Wings normal. ......... 3 3. Posterior (i. e. the 'anterior basal') cross-vein present, the second basal cell complete. ........ 4 Posterior cross-vein absent, no second basal cell. ... 14 4. Antennae with fifteen joints in both sexes, rarely twelve or four- teen jointed in the female; long plumose in the male, penulti- mate joint elongate, apical joint very small. {Tanypus, sens. lat.) -5 Antennae of the male with nine or with fourteen joints, the female with seven or eight joints. ....... 12 5. Wings bare, . 6 Wings hairy 9 6. Fork of the fifth vein petiolate. ...... 7 Furcation of the fifth vein slightly proximad of the posterior cross-vein. .......... 8 7. First vein forked at its extremity (9) . . Procladius Skuse. First vein simple Psilotansnpus Kieffer. 8. First vein forked at its extremity. . Anatopynia Johannsen. First vein simple Protanypus Keiffer. 114 NORTH x^MERICAN DIPTKRA. 9. Fork of the fifth v^ein petiolate. ...... 10 Furcation of the fifth vein slightly proxiniad of the posterior cross-vein. .......... 11 10. First vein forked at its extremity (9) . . . . Tanypus. First vein simple. .... Trichotanypus Kieffer. 11. First vein forked at its extremity. Ablabesmyia Johannsen. Fork of the first vein and the second vein pale and indistinct; an- tennae of the female twelve jointed. . Isoplastus Skuse. 12. Fourth tarsal joint shorter than the fifth, obcordate. . . 13 Fourth tarsal joint linear. . . . Prodiamesa Kieffer. 13. Antennae of the male with fourteen plumose joints; terminal joint very long; antennae of the female with seven or eight short haired joints (8) Diamesa. Antennae of both sexes short-haired, the terminal joint oval; those of the male with nine, of the female with eight joints. (The female does not seem to differ from Diamesa.) Eutanypus. 14. Thorax with a median longitudinal fissure; small species, usually with blackish wings having white markings. Ohasmatonotus Thorax without longitudinal fissure. . . . . . 15 15. Claws cleft; first vein ending not far from the tip of wing; anten- nae seven jointed in both sexes. . . Telmatogeton. Claws not cleft, though sometimes toothed on the side. . 16 16. First vein thickened at apex, anal angle of wing obsolete; antennae of the male with ten or eleven joints, of the female with six joints; very minute flies (3) . . . . Corynoneura. Not with all the above characters. . . • , .17 17. Fourth longitudinal vein simple; antennae of male with fourteen joints, closely sessile, plumose, the terminal joint cylindrical; antennae of the female with seven joints, short haired; (second and third joints sometimes more or less coalescent) . Chirono- nms, sens. lat. ......... 18 Fourth longitudinal vein furcate; antennae of both sexes fourteen jointed, except with Tersesthes. ..... 25 18. Fourth tarsal joint obcordate, shorter than the fifth; front meta- tarsus shorter than its tibia; wing under low magnification bare. Thalassomyia. Fourth tarsal joint linear. . . . . . . . 19 CHIRONOMID^. 11^ 19. Wings bare. . . . . . , . , ... 20 Wings hairy. .......... 23 20. Front metatarsi as long or longer than tibiae (2) . Chironomus. Front metatarsi distinctly shorter than their tibiae. . . 21 21. I^egs, especially the front pair, sharply black and white annulate. Cricotopus. IvCgs not so banded. . . . . . . . . 22 22. Posterior branch of fifth vein sinuous (15). Camptocladius. Posterior branch of the fifth vein straight or gently arched (6) . Orthocladius. SUBGKNKRA OF ORTHOCI^ADIUS. a. Eyes hairy Trichocladius Kieffer. Eyes bare b. b. Pulvilli large, empodium long and filiform. Psectrocladius Kieffer. Pulvilli wanting c. c. Empodium filiform. . . . Dactylocladius Kieffer. Empodium not distinct. . . . . Orthocladius. 23. Front metatarsi longer than their tibiae; anal angle of wings but slightly developed; anterior cross- vein very short and some- times difficult to distinguish. .... Tany tarsus. Front metatarsi shorter than their tibiae. . . . .24 24. Thorax produced conically, nipple-like, in front over the head; hind tibiae dilated and hairy. . . . Eurycnemus. Thorax moderately produced, hind tibiae not dilated. Metriocnemus . 25. Antennae with thirteen joints (counting the large basal) wings with anal angle; palpi three-jointed, penultimate joint swollen. Tersesthes. Antennae with fourteen joints in both sexes, the terminal joint only moderately elongated; male antennae plumose {Ceratopo- gon, sens, lat.) ......... 26 26. I/ast tarsal joint with empodium, either distinct or developed pul- villiform; wings usually hairy; femora without spines, tarsal claws equal. . . . . . . . . .27 lyast tarsal joint without empodium; wings usually bare. . 28 27. Empodium well developed, almost as long as the claws, these with- out setae (12, 13, 14) Ceratopogon. Il6 NORTH AMERICAN DIPTERA. SUBGENERA OF CERATOPOGON. a. Wings bare Atrichopogon Kieffer. Wings hairy. . . • . . b. b. Hind metatarsus longer than the following joint, sometimes in the male only equal. .... Ceratopogon. c. Hind metatarsus shorter than the following joint, sometimes equal in the female. . . . Forcipomyia Megerle. Empodium not so distinct, less than half as long as the claws, the latter with setse at base; hind metatarsus always longer than the following joint. {Oecacta is probably a synonym) (4) . Culicoid.es Latreille. 28. A cross-vein between the first and third veins, ... 29 No cross-vein between the first and the third veins. Bezzia Kieffer. SUBGENERA OF BEZZIA. ' a. Femora without prominent spines on the underside. Probezzia Kieffer. b. Some or all femora with spines Bezzia. 29. Femora unarmed, that is without stout black spines on the imder si(i& {Ceratolophus^ie^&r.) (5) Johannseniella Williston. Some or all the femora spinose beneath 30 30. Either fore or hind femora much thickened. . . . 31 Femora not noticeably thickened (10) . Palpomyia Megerle. SUBGENERA OF PAI^POMYIA. a. Antennae of both sexes verticillate with short hairs. Alasion Rondani. Antennae of the male plumose. . . . . b. b. Last tarsal joint with two rows of coarse spines below. Sphseromyas Stephens. Last tarsal joint hairy below. . . Palpomyia Megerle. 31. Fore femora thickened. . . . , . Heteromyia. Hind femora thickened Serromyia Megerle. ADDITIONAI. GENERIC REFERENCES FOR THE CHIRONOMID^. Johannsen. Bui. 86. N. Y. State Museum 1905. (Ablabesmyia, Ana- topynia) . Kieffer. Bui. Soc. Entom. France. 1899. Ann. Soc. Sc. Brux. XXX. 1906. " Genera Insectorum. Chironomidae. 1906. Latrielle. Gen. Crust, et Ins. IV. 1809. (Culicoides.) Megerle. In Meigen's System. Beschr. Eur. Zweifl. I. 1818. (For- cipomyia, Serromyia, Palpomyia). Rondani. Prodromus. II. 1857. (Alasion). Skuse. Proc. Linn. Soc. N. S. Wales. IV, 1889. (Procladius, Iso- plastus) . Stephens. Catalogue Brit. Ins. II. 1829. (Sphaeromyas.) Williston. Journal N. Y. Ent. Soc. XV. March, 1907. VI. I^'amily CHCIDOMYID^. Fig. 37, Diplosis pifii-radiatcs, enlarged. After Kellogg. Eggs, pupa, larva, 'breast-bone' and imago. Small, slender flies with broad wings, and long anten- nae and feet. Head small; eyes round or reniform, some- times holoptic ; ocelli usually wanting; antennae long, cylindrical or bead-like, composed of a large number of joints — ten to thirty-six; in many species the joints beaded or petiolate and verticillate, especially in the Z ; proboscis short, very rarely elongated; palpi usually with four joints. Thorax ovate; more or less convex, without transverse suture ; abdomen composed of eight segments; hypopygium composed of a pair of projecting booklets ; ovipositor sometimes much elongated. Legs long and slender; coxae not very long; tibiae without terminal spurs; the first joint of tarsi sometimes very short. Wings large, usually hairy, narrowed at the root, without alula; at the most with five, usually with but three longitudinal veins; viz, the first, the third, and the fifth; the fourth and the sixth sometimes present; the humeral cross- vein indistinct, or wanting; costal vein enclosing the entire wing; veins all weak; the fifth usu- (13) 117 Ii3 NORTH AMERICAN DIPTKRA. ally furcate; anterior cross-vein very near the root of the wing, often appearing as the beginning of the third vein, the real origin of the third vein having the appearance of a short cross- vein; only one basal cell present. The family Cecidom3dd3e includes a very large number of frail, delicate, often very minute flies, but is of the greatest interest to the biologist as well as the economic entomologist. At present about 600 species are known from Europe alone. The egg of the Cecidomyidse is somewhat elongated, rounded at both ends, orange-yellow or white in color. The time required for hatching is very variable and de- pends upon the weather, sometimes requiring a very few hours, but more generally a few days or even weeks. The larval food is almost wholly vegetable. The larvae of some species have been bred from decaying wood and bulbs, others from under the bark of trees, or from fungi. But the great majority prefer living plants, attacking the soft and green parts. Most of the larvae are mono- phagous, living almost exclusively on a single kind of plant, or at least closely allied plants; but there are cer- tain exceptions, such as C. sisymbrii, which is said to form the gall in spring on the barberry, and later in the season on a nasturtium. There are certain others which are inquilinous, that is guests or parasites in galls formed by other Cecidomyids. Finally, some live parasitically in the society of plant lice. Not a few, such as the Hes- sian fly, live upon the surface of plants, or in the axils of their leaves; but-the greater number penetrate inside the plant, producing the so-called galls. Every part of the plant from the root to the flower and the fruit is lia- ble to such attacks. With a few rare exceptions, each species attacks the same part of the plant and deforms it in the same manner. The galls cause deformations and excrescences attached to the stalk, stems, or flowers, de- CECIDOMYID^. 119 Fig. 38. Cecidomyidse. i, Lasioptera; 2, Epidosis; 3, Cecidomyia,' 4, Honnojuyia; 5, Trichopteroniyia; 6, Lestreniia; 7, Miastor; 8, Spaniocera; 9, Catocha; 10, Colpodia; 11, Heteropeza; 12, Asynapta; 13, Winnertzia; 14, Diplosis [Lestodiplosis) ; 15, Winnertzia. stroying the plant-tissue. When first hatched the larvae are colorless and translucent, with thealimentary canal showing through the skin greenish. I^ater in life they assume different shades of red or yellow. They have the extraordinary number of fourteen segments, thus forming an apparent exception to the larvae of all other insects, which as a general rule, have thirteen. The supernu- merary segment is placed between the head and first thoracic segment. The larvae have nine pairs of stigmata along the sides of the body apparent as more or less nip- ple-shaped projections. The head is not differentiated; I20 NORTH AMERICAN DIPTKRA. the jaws are rudimentary and there are large two-jointed palpi or antennae. The last abdominal segment is smooth and rounded, sometimes with tubercles or a pair of horny processes which are said to be used by the larvae in leap- ing. On the under side of the body at the junction of the first thoracic with the supernumerary segment there is a horny, more or less elongated appendage whose use or homology is unknown. It varies in shape in different species, the free end sometimes terminating in two points, sometimes in one, sometimes toothed and serrated. This organ, the spathida sternalis of Mik, has been called by Osten Sacken the 'breast bone'; in England it is known as the 'anchor process'. (See figure of Diplosis pi7ii-radi- at/<2'). ... 6 XYLOPHAGIN^. 3. All four posterior veins (i. e. the veins separating the posterior cells) arise from the discal cell; head small, scutellum with two spinous protuberances {(JcenomyincE) (fiig- 52, 3, 4). Coenomyia. The last posterior vein arises from the second basal cell, the fifth posterior cell hence not at all contiguous with the discal cell; scutellum without spines. ....... 4 4. Flagellum of antennae acute at tip, eight-jointed; tibial spiirs 1:2:2. Arthropeas. Flagellum of antennae not acute at tip. ..... 5 5. Fourth posterior cell closed; flagellum of antennae much elongated, composed of numerous (twenty-thirty) distinct divisions, often pectinate; eyes emarginate near the antennae (20) [Rhdchice- rincE . . . Rhachicerus. Fourth posterior cell open; flagellum composed of eight segments, less distinctly separated and never pectinate (12, 13). Xylophagus. ARTHROCKRATIN^. 6. Fourth posterior cell open, , . . . . . . 7 Fourth posterior cell closed (17, and 7, 8 Stratiomyidce) . Xylomyia. 7. Face projecting on each side in a rounded, subconical protuberance, thickly covered with hair (16) . . . . , Glutops. Face with two, deep, diverging furrows, running from base of an- tennae to oral margin (18, 19) , . . . Arthroceras. LKPTID^. 163 8. Front tibiae without terminal spurs. ..... 10 Front tibiae with a single terminal spur; hind tibiae with two. 9 Front tibiae with two terminal spurs; hind tibiae with two. Triptotricha. 9. Antennal style slender and jointed; fourth posterior cell closed (6) . Pheneus. Terminal arista not jointed; fourth posterior cell sometimes want- ing (14, 15) Dialysis. 10. Discal cell wanting; four posterior cells only (1, 2) . Hilarimorpha. Discal cell present; five posterior cells. . . . . 11 11. Third joint of the antennae round, oval or pointed. . . 13 Third joint of the antennae kidney-shaped, with a dorsal or sub- dorsal arista 12 12. Hind tibiae with a single spur; anal cell open; first antennal joint elongate and thickened (8) . . . . Symphoromyia. Hind tibiae with two spurs; anal cell closed; first antennal joint not elongate and thickened (9, 21) .... Atherix. 13. Hind tibiae with two spurs; anal cell open (fig. 51). Leptis. Hind tibiae with a single spur; anal cell closed. ... 14 14. Third antennal joint onion-shaped or conical, with a slender, arcu- ate, terminal bristle (6, 7) Chrysopila. Third antennal joint elongate; not with a slender terminal bristle. 15 15. Third antennal joint with a short terminal style (10) . Ptiollna. Third antennal joint emarginate above, pointed, without style (11) . Spania. Bolbomyia. 'More or less related to Rupellia, and may be placed among the Xylophagidae, its somewhat aberrant venation notwith- standing. Characteristic is the shape of the antennae; the third joint consists of four or five divisions, the first of which is much larger and swollen'. L/oew. ^. /mwa. District of Columbia. Length about three millimeters. This species has not been recognized since its descrip- tion, nor the genus. Possibly it belongs to the Therevidafe. XIV. Family STRATIOMYID^. Small to moderately large, nearly bare or thinly pilose, bristleless species. Head short, hemispherical or flat- tened, as broad as the thorax. Ocelli present. Eyes contiguous or separated by the front in the male. Anten- nae porrect, approximated at the base, three-jointed, the third joint always complex, usually with a terminal style or an arista. Proboscis never elongated; palpi two-joint- ed, sometimes rudimentary. Thorax never strongly con- vex; scutellum often with tubercles, spines or projections on its margin, perhaps more exaggerated here than among any other group of flies (see fig. 65, 36). Abdomen composed of from five to seven segments, usually flat- tened, often elongated. Legs never thickly pilose; with- out bristles, the tibiae without spurs*; pulvilli and empo- dia pad-like. The costal vein does not reach beyond tip of the wing; veins often crowded anteriorly, and those posteriorly weak; discal cell present; four or five poste- rior cells, and one or two submarginal cells present, the anterior branch of the third vein short and often indistinct or wanting. The famil}^ Stratiomyidae is one of considerable size, including about a thousand known species. The flies are invariably flower insects, seldom with any marked powers of flight and never having the habit of hovering in the air. Not a few species are caught in the beating net or on the windows of dwelling houses. Man}^ of the * Xylomyia (7, 8) which Osten Sacken and Austen insist belongs in this family, has spurs on the middle and hind tibiae and the costal vein encompasses the wing. 164 i^^ft' 55- Chrysochlora. Fig. 56. Rhaphiocera. Fig. 57. Ptecticus. STRATIOMYID^. 165 Species have in life bright yellow or green markings. The eggs, such as have been observed, are laid on the ground, on plants about water, or perhaps on the surface of the water itself. The larvae are carnivorous, or feed upon decaying vegetable material. The larvae of Myio- clijysa have been found in cow-dung, and under stones; those of Geosargus in the flowing sap of elm trees; those of Hennetia in priv- ies ; those of Pachygaster and Zabrachia in decaying wood; those of B eris in moss; ihos^oiStratiomyia, Odo n to niyia , Ne 7notelus, etc., in water. The larvae of Stratiomyia have been observed in salt and alka- line water. The body is smooth and flattened, the last segment often prolonged into an elongated breathing tube and having a terminal transverse cleft. The pu- pae are inactive, develop- ing within the larval skin, the pupal skin remaining within, or partially within, the larval skin when the fly escapes through a longitudinal or trans- verse rent. Fig. 58. Cyphouiyia; female, enlarged. 17 i66 NORTH AMERICAN DIPTERA. Fig. 59. Stratioiiiyidse. (See next page. STRx^TIOMYID^. 167 Figs. 59, 60. Stratiomyidae. i, Chiroinyza, wing; 2, Beris, wing; 3, Beris, antennae; 4, Cynipimorpha, scutellum; 5, Cynipimorpha, wing; 6, Acantliina, wing; 7, Xylomyia, wing; 8, Xylomyia, antenna; 9, Hermetia, wing; 10, Hernietia, antenna; 11, Odontomyia, wing; 12, Odontoniyia, antenna; 13, Stratiomyia, antenna; 14, Geosargiis, wing; 15, Ptectiais, wing: 16, Piecticus, antenna; 17, Cyphomyia, an- tenna; 18, i\/erosar<^us, antenna; 19, Histiodroma, wing; 20, Eupa- rhyphus,^N\VL'^ji\ 21, Euparhyphus, antenna; 22, Euryneura,\\^2AivQn\ in front ; 23.' Pelagomyia, head ; 24, Nemotelus, head ; 25 Aochle- tus. antenna; 26, A nalcocenis, wing; 27, Pachygaster, head; 28, Scoliopelta (type), head; 29 Microchrysa, wing; 30, Clitellaria, head; 3T, Rhaphiocera, wing; 32, Myxosargtis, head; 33, Allognosta, wing; 34, ('hrysoc/ilora, antenna; 35, Rhingiopsis, head; 36, Dicranophora. l5S NORTH AMERICAN DIPTERA. TABIvE OF GENERA. 1. Abdomen with seven visible segments.. .... 5 Abdomen with five or six visible segments. .... 2 2. Three posterior veins, all arising from the discal cell. . . 38 P^onr posterior veins, the first and third sometimes vestigial l)ut at least represented by angulations of the discal cell. . 3 3. All the posterior veins arise from the discal cell, the fifth posterior cell hence contiguous proximally with the discal cell. . 29 The last posterior vein arises from the second basal cell. . 4 4. Antennae with an elongate terminal or dorsal arista. . . 11 Third antennal joint not with a distinctly differentiated arista, its segments homologous or nearly so. . . . . . 20 BKRIBIN^. 5. Three posterior veins, all arising from the discal cell."^ . 6 Four posterior veins, or vestiges of them, all arising from the dis- cal cell; scutellum with spines. ...... 10 6. Scutellum with spines. . . . . . . , 8 Scutellum without spines. ....... 7 7. Short, small species; third vein with an anterior branch (33). Allognosta. More elongate and larger species, especially in the female; third vein simple (1) Chiromyza. 8. Scutellum with ten spines. .... Heteracantha. Scutellum with less than ten spines. ..... 9 9. Head hemispherical (2,3). ...... Beris. Head not hemispherical; the antennae situated low down, the frontal region long and plane. .... Berismyia. 10. Hind femora thickened. ..'... Neoexaireta. Hind tibiae thickened at extremity, t .... Actina. * The third vein rarely arises from the basal cell in species of Beris. t The genus Actina, to which Beris viridis has been referred, has a dichoptic head in the male, four posterior veins arising from the dis- cal cell, thickened distal extremity of the tibiae, etc. Osten Sacken has given as the chief distinction of the genus from Beris the well- developed palpi, vestigial in Bens. In our species of Beris, how- ever, the palpi are of considerable size. Beris viridis differs from other species of the genus in having dichoptic eyes in the male; but its venation is typically that of Beris. STRATIOMYID^. l6g SARGIN^. 11. Scutellum with spines. . . . . . . . . 12 Scutellum without spines 14 12. Third vein with anterior branch (fig. 54; 31). Rhaphiocera. Third vein without anterior branch. . . . . . 13 13. Scutellum produced into a stout median process, bearing two di- varicate spines at its tip (36) . Dicr anaphora, S. A. Scutellum with marginal spines. . . . Nothomyia. 14. Second longitudinal vein coalescent with the first in a broad ex- pansion of the costa; antennae moderately long, the long arista flattened (19) Histiodroma. Wings not with an anterior distal expansion of the costa. . 1 5 15. Anterior ocellus more widely separated than the other two; males holoptic or dichoptic. . . . . . . . 16 Ocelli equidistant, more approximate 17 16. Abdomen contracted at its base, clavate or pedicillate Macrosargus*. Abdomen not clavate or pedicillate (14) {Sargus) . .Geosargus. 17. Second antennal joint prolonged on the inner side, closely over- lying the third joint (fig. 56, 15, 16) . . Ptecticus. Second antennal joint not with such a projection. . . 18 18. Third joint of antennae elongate, composed of four segments, with a long terminal arista thickened and pubescent at its base. Acrochasta. Third antennal joint short, oval or subulate, with an apical or pre- apical arista. ......... 19 19. Hind femora moderately thickened at base; non-metallic, more or less yellow species (18) Merosargus. Hind femora not more thickened at base; usually blue, green and metallic species, elongate. . . . Chrysochroraa. Hind femora slender; small, deep-colored species; the holoptic eyes of the male with an area of enlarged facets above; eyes hairy [Myiochrysa); or hare (29). . . . Microchrysa. STRATIOMYIN^. 20. Third vein with an anterior branch. ..... 21 Third vein without anterior branch; scutellum spinose. . 28 ^ The genus Macrosargiis is so feebly differentiated that I do not think it can be maintained. If not, the name must take preference over Geosargus Bezzi, substituted for Sargus, preoccupied. lyo NORTH AMERICAN DIPTKRA. 21. Sciitelliim without spines; first two joints of antennae short. Ohordonota. Scntelluni with spines, rarely absent in species of Odontornvia. 22 22. Costa thickened distally in front; antennae elongate, the flagelhim composed of six closely united segments (26) . Analcocerus. Costa not thickened distally in front. ..... 23 23. Third antennal joint composed of four, five or six closely united segments. .......... 24 Third antennal joint composed of seven or eight closely united segments. .......... 26 24. Head strongly produced forward for insertion of the antennae, the face much retreating [Proineranisa, S. A.) Head not strongly produced forward. ..... 25 25. First antennal joint three or more times the length of the second (13). Stratiomyia. First antennal joint less than three times the length of the second (11, 12) Odontomyia. 26. First antennal joint two or three times the length of the second, the third much elongated, . . . . . . 27 First antennal joint but little longer than the second, the third terminating in a bristle. .... Neorondania. 27. Thorax narrowed anteriorly; bod}- with green and yellow mark- ings Campeprosopa. Thorax not narrowed in front; body black, not with green and yellow markings; posterior orbits of female often conspicuously tumid and colored (fig. 58; 17). . . . Oyphomyia, 28. Head strongly produced anteriorly, with a porrect spine immedi- ately below the insertion of antennae {Rhin^iopsis, S. A. 35.) Head not projecting, the face produced conically downward; third joint of antennae composed of six* segments (32) . Myxosargus. CLITELLARIN^. 29. Scutellum with spines. ........ 30 Scutellum without spines. ....... 35 * The genus Myxosargus was described by Brauer as having eight segments in the third joint of the antennae, the segments distinguish- able with difficulty. The species referred by me to this genus have but six segments in the third joint, easily distinguishable. The posterior orbits of the female are thin and expanded, and the females of all the species have one or more conspicuous tubercles on the front. STRATIOMYID^. lyi 30. Antennae short, with a subterminal arista. . . Oxycera. Antennae more or less elongate . 31 31. Antennae situated near the oral margin, third joint composed of five or six segments (22) . .... Euryneura. Antennae situated near middle of head in profile. . . 32 32. Antennae much elongated; style not differentiated; eyes bare; smaller species (20, 21) . . . . . Euparhyphus. Antennae moderately elongated . 33 33. St3de of antennae not differentiated; eyes pubescent; occiput flat- tened (28) Scoliopelta. Style of antennae distinctly differentiated, .... 34 34. Eyes pubescent; antennae with a slender style (30) . Olitellaria. Eyes bare; style not slender (25) .... Aochletus. 35. Face produced conically. ....... 36 Face not produced. ........ 37 36. Males lioloptic (24). Nemotelus. Males dichoptic . Alisonia. 37. The third antennal joint terminates in a very long, densely fringed, lamelliform style; large, elongate species; eyes pubescent or bare (9,10) Hermetia. Third joint of antennae with a short, thickset, differentiated style terminating in a short bristle ; eyes pubescent ; moderate sized species (23). . . . . . . . Pelagomyia. The third antennal joint tapers into a long, thickened, or styliform arista, the basal two-thirds of which is short but densely plu- mose, the distal extremity bristly; eyes bare {Cacosis, S. A.). The third antennal joint terminates in a long slender arista, not at all pubescent or hairy at base; eyes bare, large species (fig. 55; 34). . Ohrysochlora PACHYGASTRIN^. 38. Antennae situated near or toward the oral margin; scutellum spin- ose; males holoptic; eyes pubescent. .... 39 Antennae situated near the middle of the head in profile. . 43 39. Third joint of antennae forked; scutellum quadrispinose. . 42 Third joint of antennae not forked. ..... 40 40. Third joint of antennae elongate, with a short, differentiated style; scutellum quadrispinose (6) ... . . Acanthina. Third joint of antennae shorter; ending in a l)ristle. . . 41 1^2 NORTH AMERICAN DIPTKRA. 41. Third joint antennae oblong, with its apex attenuated, the arista bare; scutellum bispinose {Spyridopa, S. A.). Third joint subglobose; scutellum bispinose [Panacris, S. A.) 42. Upper branch of antennae with a terminal arista and a lateral pro- cess. Neochauna. Upper branch with a short, slender style and no lateral process [Blastocera, S. A.). 43. The scutellum terminates in a stout median spine or process (4, 5) Oynipimor pha . Scutellum without median spine or process, simple. . . 44 44. Third vein with an anterior branch. ..... 45 Third vein without branch. , . . . . Zabrachia. 45. Third antennal joint oval, with its terminal arista briefly but densely plumose Lophoteles. Third joint rounded or oval, its terminal arista bare (27) . Pachygaster. The relationships of the genera allied to Sargus {Geosargus) — Mero- sargus, Macrosargus [Pedtcella Bigot) , Chrysochroma, Microchrysa and Myiochrysa, are all more or less doubtful. Kven Ptecticus can not be sharply limited by the structure of the second antennal joint, I suspect that Pedtcella will have to take precedence over Sargus; Macrosargus and Geosarg us,. Sind that Chrysochroma will have to be merged into Merosargus. The whole group sadly needs revision. The: genus Nothomyia, which I do not know, may perhaps find its proper place under 28. XV. Family ACANTHOMERID^, Fii^". (n. Acanthoniera ■>^., ^^ Venezuela; natural size. Very large, stout, bristleless, nearly bare flies. Eyes large, contiguous in the male. Ocelli present. Third joint of the antennae complex, composed of seven seg- ments, with a terminal, often in the male setiform style. Proboscis short, not adapted for piercing, with fleshy la- bella; palpi two-jointed. Squamae rudimentary. Tibiae without spurs; pulvilli and empodia pad-like. Wings with two submarginal and five posterior cells, the fourth posterior ceil and the anal cell closed. But two genera are known in this family, including al- together only about fifteen or sixteen species, all of which are inhabitants of Central and South America. The spe- cies of Acanthomera are found in forests, alighting on trunks of trees, according to Mr. Champion; otherwise their habits, whether of the adult or immature stages, are but little known. Brauer has figured and described the larvae of A. frauenfeldii. They are cylindrical, thick and short. The last segment is firmly chitinized above 173 iy4 NORTH AMERICAN DIPTERA. wilh two series of booklets, the two projecting backward in the middle being stout and curved; below these there is a deep, transverse cleft, on the under side of which is a rounded lip. Fig. 62. Acanthoniera, sp. wing. In both Aca?ithomera and Rhaphiorhynchus the face may be produced conically or not at all. The two genera are distinguished by the structure of the second joint of the palpi, in Acanthomera slender, in Rhaphiorhynchus stout and pointed. Both genera may have a spine on the under side of the hind femora. Osten Sacken has alread}^ commented upon the sup- posed distinctions between Acanthomera and Rhaphio- rhynchtis, making it clear that only the palpal character is of service, and even that is doubtful since it may be only sexual. I have examined five or six species of the family and am very skeptical of the validity of Rhaphio- rhynchus. There are apparently no valid nor just reasons for the retention of the generic name Acaiithomera. Wiedemann more than once, arbitrarily and without giving reasons, rejected the earlier names of genera and species for ones of his own creation, and the present seems to be one of the most flagrant examples. The description and figure ACANTHOMERID^. ly^ of Payitophthahnus tabaninus Thunberg leiave no doubt of the form to which they apply, and the description was published two years earlier than that of Acanthomera, and was quoted by Wiedemann. Possibly Wiedemann thought the name inappropriate, but, to say the least, it is no more inappropriate than his Acanthomera, in which the 'spiny femora' may be only an individual character, cer- tainly not generic. The relationships of the family are very close indeed to the Stratiomyidae, and the families might, very prop- erl}^ be united. XVI. Family TABANID^. BY PROF. J. S. HINK. Fig. 63. Taba7ius lineola\ enlarged. After Lugger. Head large, the occiput flattened or concave. Antennae porrect, the third joint composed of from four to eight segments or annuli. Byes large, pubescent or bare, con- tiguous above in the male, and often with some of the facets much larger than the others; in the living insect of either sex usually with green or purple bands or spots. Ocelli present or absent. Proboscis projecting, some- times as long as or longer than the body ; palpi two-joint- ed, that is with one movably articulated joint, which is variable in length and thickness in different genera. Thorax and abdomen clothed with fine hairs, never with bristles. Abdomen broad, never constricted at the base, composed of seven visible segments ; genitalia never prominent. Legs moderately stout, the tibiae sometimes much dilated; middle tibiae always with two spurs at tip; empodium developed pulvilliform, the pulvilli al- ways present. Wings but little variable; two submar- 176 TABANID^. 177 ginal and five posterior cells always present ; basal cells large, anal cell usually closed, but never far before the border of the wing; the marginal vein encompasses the entire wing. Squamae of considerable size. Flies of mod- erate or large size, never slender; rarely with brilliant colors. Fig. 64. Pangonia guttata; enlarged. This family includes the insects commonly called horse- flies, green-headed flies, etc., and has a wide distribution over the world. About eighteen hundred species have received names, of which not less than two hundred and seventy-five are from North America. None of the spe- cies are active on dark, cloudy days, though some are partial to shady woods, and are very annoying to stock in such places. On clear, warm days, horseflies begin flying as soon as the sun has warmed the air, and are 18 lyS NORTH AMERICAN DIPTERA. usually most active toward the latter part of the fore- noon, although they are plentiful about cattle and horses during most of the time while the sun is shining. The females only are bloodsucking in habit; the males feed upon the juices of plants, the honey-dew secreted by plant-lice and scale insects, and similar substances. The females also will feed as the males do, when nothing more to their liking is procurable. Their bites are pain- ful, but are not usually attended with that inflammation or swelling characteristic of the mosquitoes andpunkies. Most species of Tabanidse may be collected in various situations. Sweeping the grasses and weeds of marshy places, collecting from fences and trunks of trees in the early morning, or from plants much infested by plant- lice or certain scale insects throughout the day, netting specimens that fly about stock or the collector's own head, or that may be found upon various flowers, or cap- turing such as may enter the doors and alight upon the windows, all are productive of results. Collections made in these ways are pretty sure to represent well the tabanid fauna of any locality. The eggs of the Tabanidse are deposited in large masses on the stems and leaves of plants or in similar places over water or in marshy land. They are spindle-shaped, brown or black in color, and, in ordinary summer temp- erature, hatch in from seven to nine days The larvae feed upon various small creatures, and in such cases as have been observed reach maturity and change to pupae the following spring. The pupal stage is completed in three or four weeks, the whole cycle from the deposition of the eggs to imaginal maturity thus requiring about eleven months for its completion. The larvae may be sought for in rotting logs and stumps, in the soil in the vicinity of ponds, under stones about ditches, or swim- TABANID^. 179 ming free in the water; indeed one may occasionally find them in the most unexpected places. The pupae are difficult to find in nature, though they usually rest near the surface of the ground wherever the larvae come to maturity. I^arvae taken in the spring are easily reared in jars of moist earth on a diet of angle worms; but only a single specimen can be reared in each jar, for they are cannibalistic in nature. The body of the larvae is eleven- segmented, each segment usually encircled by a row of fleshy protuberances, which are most pronounced on the Fig. 65. Tabanidse. i, Tabanus, wing; 2, 3, Tabanus, antennae, 4, Dichelacera, antenna; 5, Snowielliis, head, side; 6, H csniatopota head, in front; 7, Diachlorus, head, front; 9, Lepidoselaga, front leg; \o,StibasO}na,\&%\ 11, Chrysops, head; 12, Chrysops, leg; 13, Goniops, head, front; 14, Silvius, antenna; 15, Apatolestes, head, front; 16, Pity- ocera, antenna (CTi<ichus, head; 13, Lasia, wing; 14, Lasia, head. 1 84 NORTH AMERICAN DIPTKRA. ing between forms otherwise related. In the few forms in which the larvae are known they are parasitic upon spiders or their cocoons. 'In the spring of 1887, while hunting for spiders, I found hanging in cobwebs several soft white maggots and pupae. The webs were generally old and out of repair, and a closer examination showed that no living spider was in them, but almost every one had an empty skin of a common spider Amaurobius sylves- tris, nearly full grown. The skin of the legs and thorax was not clean like a moulted skin, but dirty and opaque, as though eaten out, and the skin of the abdomen when present was torn and shriveled. From this I concluded that the maggots came out of the spiders, and from their size must have nearly filled them. The maggots varied considerably in size, the largest being a quarter of an inch long, while others w^ere not more than half as large. The hinder half of the body was thicker than the front half and nearly spherical. They hung head downward, holding to the web by their jaws and were also partly supported by threads under and around them.' The author of the foregoing, J. H. Emerton, reared from other specimens of these larvae a fly belonging to the genus Aciocera. The larvae of Astomella lindelii, according to Brauer, are so lodged in the abdomen of the spider that the posterior terminal stigmata are in relation with the lung-tubes of the spider. The eggs are said to be de- posited on dried twigs. TABLE OF GENERA. 1. Antennae without terminal arista or style. .... 2 Antennae with a terminal arista. ...... 3 2. Antennae short, third joint rounded, with terminal bristly hairs. 3 Antennae elongate. ........ 7 3. Antennae inserted below the middle of the head in profile. . 4 Antennae inserted above the middle of the head. ... 6 CYRTID.^. 185 4. Wings with a stout costal spur near the tip of first vein (7, 8) Pterodontia. Wings without such spur. ....... 5 5. Proboscis small or vestigial"^ {5,Q). . . . Oncodes. Proboscis elongate, directed backward; prothoracic lobes broadly- united above (3, 4) . Philopota. 6. Venation complete; eyes pilose (fig. 66) . . , Opsebius. Venation more or less obsolete; eyes bare (1, 2). . Acrocera. 7. Proboscis very small, vestigial. ...... 8 Proboscis elongate. ......... 10 8. Kyes bare. . ^ Appeleia. Eyes pilose or pubescent. ....... 9 9. Third joint of antennae with terminal bristly hairs. Pialeoidea. Third antennal joint not with terminal bristly hairs (9, 10). Ocnaea. 10. Ocelli wanting; large flies (13, 14) . .... Lasia. Ocelli present; moderately large flies (11,12). . Eulonchus. * Compare Nothra ainericmia Bigot. The occurrence of this genus in North America is doubtful. If, however, Bigot correctly recognized it, the species should be sought for under Oncodes. XVIII. Family NEMISTRINID^. Species of moderate size, not elongate, thinly or densely pilose. Venation complicated; the fourth and fifth veins are curved forward to terminate before the tip of the wing; the anterior cross-vein is obsolete, that is the third and fourth veins coalesce for a short distance; basal cells long. Antennae small, short; third joint simple, with a terminal, slender, jointed style. Proboscis sometimes elongate. Ovipositor of the female elongate, often slen- der. Tibiae without spurs; empodia developed pulvilli- form, but, with the pulvilli often minute. (See fig. 69.) Fig. 68. Wing of Rhynchocephalus volatiais. a, third submarginal cell; b—-t\ first — fifth posterior cells. Throughout the world about one hundred species of this family are known, the larger part of which are from South America and Australia. Only six species are known from North America and two or three from all Europe. Some of the species have the wings with nu- merous cross-veins, almost recticulate in appearance. Megistorhynchus longirostris from Africa, though only about two-thirds of an inch in length, has a proboscis nearly three inches long. The adults are flower flies, resembling in their habits the Bombyliidse. But little is known of the larvae. The females of Hii^- Tnoneura obscura have been observed laying their eggs deeply within the burrows of Afithaxia, a wood-boring 1S6 NEMISTRINID^. 187 insect, in the pine rails of fences. The eggs were found in clusters and the young larvae hatched from them differ- ed very singularly from those of a more mature growth. They were more slender, but differed chiefly in having each of the abdominal segments from the sixth to the twelfth provided with a pair of false legs bearing a single elon- gate seta at the tip, the hooks pointing backward; on the thirteenth segment there were two pairs of similar setae, the hooks of which, however, pointed forwards, thus en- abling the larva to attach itself firmly and raise itself erect. These young larvae issued in great numbers from the burrows in which they were hatched and, placing themselves erect, were blown away by the wind. Here for a time they have not been followed, but it is probable that they attach themselves by the aid of the ventral hooks to the bodies of large-sized beetles, by which they are carried into the ground when the females enter to de- posit their eggs. This is probable from the fact that hundreds of pupae and pupa skins were observed near the fence. On. searching below these the larval skins were found at a depth of about two inches, and still deeper were found the remains of the beetles, Rhizotrogus solsti- tialis, in some instances with the larvae yet within them. Females of Rhynchocephalus sackeni have been observed by Bruner apparently depositing eggs in the stems of Eriogonum alatuTn. TABIvK OF GENKRA. I. Proboscis short, protruding but little from the oral opening; eyes bare or pilose; two or three submarginal cells. Hirmoneura. Proboscis long; antennae broadly separated; eyes bare; ovipositor composed of two slender lameilse; three submarginal cells present (fig. 68). .... Rhynchocephalus. XIX. I^AMii^Y APIOCKRID^. Rather large, elongate, chsetophorous, thinly pilose flies. Antennae three-jointed, with or without a small, short style. Front not excavated, broader in the female. Ocelli present. F'ace short. Proboscis not adapted for piercing, the labella not horny. Third longitudinal vein of wings usually furcate; basal cells large; five posterior cells present. Bmpodia wanting. Male forceps enlarged. Fig; 71. Apioceridae. Apiocera hartispe.v, head; 2, Apiocera har- uspex, wing; 3, Apiocera, sp. (Australia! wing; 4, Apiocera (gen. nov. Australia) wing ; 5, Rhaphioniidas acton, head ; 6, Rhaphioniidas acton, wing. Less than a score of species of this family are known throughout the world, seven of which have been de- scribed from North America. The genera have been variously placed among the Mydaidse, Asilidse and 188 Fig. 69. Trichophthalma, species (Nemestrinidae); enlarged. Fig. 70. Apiocera, species; enlarged. (Australia.) APIOCERID^. 189 Therevidae, but seem best isolated into a distinct group, though the relationships of Rhaphiomidas with the My- daidse are evident; perhaps as close as with Apiocera. The members of the genus Apiocej'a have much the ap- pearance of large Therevidse or of Asilidse, from which they will be at once distinguished by the anterior curva- ture of the third and fourth veins of the wings. The larvae are unknown. See fig. 70. TABLE OF GENERA. I. Palpi two-jointed, large; the second vein from the discal cell ter- minates beyond the tip of the wing (1, 2) . . Apiocera. Palpi one-jointed, small; the second vein from the discal cell ter- minates before the tip of the wing; proboscis elongate {Aponii- das) {5,Q) Rhaphiomidas. 19 XX. Family MYDAID^. Rather large to very large (see fig. i, page i6), thinly clothed or bare, elongated flies. Venation complicated, the basal cells long, the fourth vein always terminating at or before the tip of the wing; posterior branch of fourth sometimes present and terminating also before the tip of the wing, as in Rhaphiomidas (Apioceridae), but not present in American species. Antennae composed of -four joints, the fourth always, the third usually elongate. Front excavated betv\^een the eyes; both sexes dichoptic; ocelli wanting. Proboscis with fleshy labella, and with- out palpi (in our species). Kmpodia very little devel- oped, not pulvilliform. Fig. 72. Mydaidse. i, Dolichogaster, wing; 2, Dolichogasier, antenna; 3, Mydas, antenna. The family Mydaidae comprises only about a hundred known species, more abundantly represented in Austra- lia, Africa, South and Central America. The family 190 MYDAID^. igj comprises the largest of known diptera. The relation- ships of the family are very close with Rhaphiomidas of the Apioceridse, through the Tricloninae. The larvae of species of Mydas live in decaying wood, and it is probable that other members of the family have similar habits. They are known to be predaceous in some cases upon the larvae of beetles. The larvae of M. fulvipes are nearly two inches in length, with swellings below the abdominal segments for locomotion; the body is depressed and somewhat widened, with the posterior extremity broader and somewhat obtuse. The pupa of M. clavatus has at its anterior end two strong, sharp, out- wardly curved hooks ; the first abdominal segment has at its anterior border above, a row of very long, erect spines, curved backward at the tip. Another series of spines is situated on the anterior border of the last seg- ment; and, on the same segment there is a pair of hooks at the tip curved downward. TABIvE OF GENERA. 1. Terminal segment of the female abdomen with a circlet of spines. 3 Terminal segment of female abdomen without circlet of spines. 2 2. Antennae but little longer than the head, the third short and the fourth expanded ; cross-vein between the second and fourth posterior cells present or not (1, 2). . Dolichogaster. Antennae much longer than the head, the third and fourth joints elongated; the latter moderately or but slightly expanded [Vhy- loniidas)^. (Fig. i, and 3.) . . . , . Mydas. 3. Hind tibiae of female with spur; a short vein ends in hind margin of the wing between the second and fourth posterior cells. Ectyphus. Hind tibiae of female without terminal spur; no such cross- vein; proboscis elongate. Leptomydas. * I have examined specimens of Phylomidas phylocerus, the type species of the genus, from Norton County, Kansas, in the University of Kansas Museum. The genus is not valid, differing from Mydas only in the more expanded fourth antennal joint. XXI. Family ASILID^. Fig. 75. Promachiis vertebratus, nsiiuraX s\7.&. After Washburn. Species cf moderate to large size, rarely small ; usu- ally more or less elongate in form, sometimes thickly hairy; always bristly, the bristles sometimes conspicu- ously strong; highly predaceous in habit. Head flatten- ed, broad and short, separated from the thorax by a freely movable neck. Front excavated between the eyes, dichoptic in both sexes, the front of the male not narrow- ed. Ocelli present, usually situated upon a rounded tubercle; front with bristles. Antennae porrect, simple, usually composed of three simple joints, the third more or less elongate, and wnth or without a terminal style or arista, the bristle exceptionally pectinate; sometimes the so-called style is thickened, forming one or two an- tennal joints. Proboscis never markedly elongate; firm and horny, adapted for piercing, directed downward, or downward and forward; labella never fleshy; palpi com- posed of one or two joints. Abdomen composed of eight 192 Fig. 73. Craspedia coriaria Life size. Fig. 74. Erax qtiadrimaculatus . Three times natural size. ASIIvID^. 193 segments, tlie hypopygium and ovipositor usually promi- nent, lyegs strong, bristly, of moderate length, rarely elongate and slender; tarsi strong; empodium bristle- like (31) or wanting, the pulvilli rarely vestigial. Squa- mae small. Wings when at rest lying parallel over the abdomen; basal cells long; two or three submarginal andfive posterior (four in Townseiidia and Leptopfero?nyia, 35) cells present; first and fourth posterior and the anal cells closed or open. (Figs. 73 and 74.) The family Asilidae, or Robber-flies is one of the larg- est and best known among diptera, including about three thousand species, distributed in more than one hundred and fifty genera. Many of the species are conspicuous for their large size, the largest measuring nearly two inches in length, while the smallest known species is over four millimeters. They are, perhaps, the most pre- daceous of all flies in their habits. The greater part of them rest upon the ground in wait for their prey, arising with a quick buzzing sound when disturbed, to alight a short distance beyond. Some of the lyaphrinae have a striking resemblance to humble bees, and are usually observed resting up- on foliage about the borders of forests. All their food, which consists wholly of other insects, is caught upon the wing; their luckless victims when once seiz- Fig. 76. DasyUis, species; j 1 ^1. • . z . natural size. After Kellogg, ^d by their strong feet are pow- erless to escape. Their prey is usually other flies and h3anenoptera, but flying beetles, especially the Cicindelae, are often caught, and they are known to capture and destroy large dragonflies. In one instance that the writer observed, a female seized a pair of her own species, and thrusting her proboscis into the 194 NORTH AMERICAN DIPTERA. 16 '^R\S>' ASILID^. 195 Fig. 76. Asilidse. i, Leptogaster, wing; 2, Leptogaster, antenna; 3, Leptogaster, end of tarsus (claw mostly cut away); 4, Datnalis occi- dejilalis, antenna.; 5, Dicraniis jaliscoerisis, claw; 6, Stenopogon {Scle- ropogon) truquii, antenna; 7, Microstyluni galactodes, wing; Psilo- ciirus, sp. antenna; 9, Laphystia^ species, antenna; 10, Ceraturgus cruciatiis, head; 11, Myelaphus nielas, head; 12, Dioctria nitida., anten- na; 13, Blepharepiumcoarctatiini, claw; 14, Der oiny ia winthefui, Yfing; 15, Deromyia, antenna; 16, Lestoniyia fraudigera, head; 17, Taracti- cns, tibial spur; 18, Taracticus, antenna; 19. Cophura, antenna; 20, Nicocles rufus, wing; 21, Pseudorus, tibial spur; 22, Atomosia puella, wing; 23. Pogonosonia dorsata, wing; 24, Dasylechia {Hyperechia) atrox, head; 25, Dasyllis, antenna; 26, Laphrta, wing; 27, Oninia- tius tibialis, antenna; 28, Eccritosia {Proctacanthus) amphinonte, wing; 29, Mallophora, claw; 30, Promachus, wing; 31, Proniachus, claws; 32, Proniachus, antenna. Fig. 77. Asilidse. 34, Psilocurus caudatus, wing; 35, Leptoptero- niy i a graci /is {type, Bra7A\); 36, Holcocephala nitida, head, from in iq6 north AMERICAN DIPTERA. thorax of the male, carried them both off together. The larvae live for the most part in rotting wood, under bark, or in soil containing decomposing vegetable matter, un- der leaves, etc., and feed upon grubs and other larvae. The larvae are cylindrical in shape, with parchment-like skin, the abdominal segments sometimes girdled with rounded tubercles, or with abdominal protuberances for locomotion. The pupae are free, with strong booklets at the anterior end, the abdomen provided with spiny girdles, mixed with hairs below and behind; the last seg- ment has two short, divaricate booklets and several smaller projections. The young larvae sometimes bore their way completely within the bodies of other larvae, remaining there till their food is wholly consumed. Often the larvae are found free in the earth, however, where their transforma- tions occur. The eggs are laid about grass stems, or in crevices of decaying logs and trees infested by the larvae of other insects. The division of the family into four subfamilies based upon the closure or non-closure of the marginal cell, and the presence or absence of a terminal bristly arista is ar- tificial in a large measure, but at the same time is very useful. I also doubt the importance of the terminal spur on the front tibiae as a true index of relationships. So far as my studies go, the structure of the palpi is a more natural character for subfamily division, the Dasypogo- ninae and lyaphrinae having two joints, the Leptogas- trinae and Asilinse one. The Leptogastrinae are, further- more, entitled to subfamily distinction because of the front; 37, Ste7iopogon [Scleropogon) truquii, head; 58, Archilestris niagnificiis, head; 39, Chrysoceria pictitarsis, head; 40, Dizonias, sp. head; 41, Pseudorus bicolor, head; 42, Atonia niikii, head; 43, Ato- tnosia niacquartii^ antenna; 44, Cerotainia^.s^^oA^?:,, antenna; 45, Lampria, species, hind leg; 46, Laphria (Ntisa) , sp., wing. ASIIylD^. 197 remarkably attenuated body and the more generalized venation. The dividing line between the Dasypogoninae and lyaphrinae will be more difficult to make, since there are forms with closed marginal cell whose natural rela- tionships are closer with the Dasypogoninse, and vice versa. It is probable that the following characters will be found the most natural, for the ordinary grouping at least : A. Palpi one-jointed; antennae with a slender terminal arista. B. Marginal cell open; very slender species. Lep togas trinse. BB. Marginal cell closed, less slender or robust species. AsilinsB. AA. Palpi two-jointed; antennae with or without a thickened terminal style; very rarely with a terminal arista, C. Marginal cell open, or rarely closed at extreme tip. Dasypogoninse. CC. Marginal cell closed. . . . . . Laphrinse. TABIvK OF GENKRA. 1. Marginal cell of wings open (14). . . . DasypogoninaB. Marginal cell closed (22, 23, etc.) . '. . . . 2 2. Antennae with a terminal bristle (32). . . . Asilinse. Antennae with or without a terminal style (24, 25). Laphrinae. DASYPOGONIN^U. Marginal cell of wings open; antennce with or without a terminal stijle or bristle. 1. Front tibiae with a terminal, claw-like spur (17). . . 32 Front tibiae not with a terminal claw-like spur. ... 2 2. Pulvilli vestigial or wanting, ...... 3 Pulvilli normal (the hind pair rarely shortened) . . . .5 3. Third joint of antennae with an arista or aristiform style; abdomen very slender; hind femora much elongated and clubbed at ex- tremity (Ivcptogastrinae) (1, 2, 3). . . Leptogaster. Antennae not with a terminal arista. ..... 4 4. Claws very long, with an elongated tooth at the base of each claw; large species (5) Dicranus. Claws normal; smaller species. .... Ablautus. igS NORTH AMERICAN DIPTERA. 5. Anteiiii£e Vi'ith a slender, terminal arista (4). . Damalis. Antennae with or without a terminal style, the latter sometimes simulating antennal joints. ...... 6 6. Only four posterior cells present; front very broad above; small species. Townsendia. Five posterior cells as usual. ....... 7 7. Head narrow, about as high as broad; face narrow above, broader and swollen below, in large part covered with hair; large, elong- ate species. ......... 7 Head very obviously broader than high. . . . . 10 8. Antennae with a terminal style. ...... 9 Third joint of antennje long, without visible style; fourth poste- rior cell closed before the border of the wing; black species, with or without red on the abdomen. . . Ospriocerus. 9. Style more than a fourth the length of the third antennal joint; a row of trichostical bristles usually present; first posterior cell usually closed (Sc/eropogon) (6, 37). . Stenopogon. Style about one-sixth the length of the third joint; trichostical bristles usually absent. ..... Stenopogon. 10. Fourth posterior cell closed in or before the margin of the wing. 11 Fourth posterior cell wide open, rarely nearly closed. . 16 11. Antennae much elongated, apparently composed of five joints. 17 Antennae less elongated; style of antennae small or vestigial, not simulating antennal joints. ...... 13 12. Face bare except on oral margin; large or ver}^ large species. 12 Face hairy or bristly. ........ 14 13. Vein posterior to the second posterior cell continuous or nearly so with the fourth vein beyond the discal cell, the last section of the fourth vein oblique, closing or much narrowing the first posterior cell (7). Micro stylum. Last section of fourth vein continuous in nearly the same direction with the penultimate section, the first posterior cell not closed or narrowed (38) Archilestris. 14. Abdomen cylindrical*, not narrowed at tip, elongate ; near the proximal margin of the second and third segments with a white_ * Compare here Sphageus; I do not know the genus and can not locate it more precisely from the description. pollinose, emarginate cross-band; wings dark; males very differ- ent in coloration from the females (40) . . . Dizonias. Abdomen less elongate, with five or six white-pollinose entire or interrupted cross-bands,* 15 15. Style of antennae vestigial ; veins at outer side of the discal and fourth posterior cells parallel or nearly so (8, 34). Psilocurus. Style distinct, though small; veins at outer side of discal and fourth posterior cells not at all parallel; marginal cell narrowly closed or open; first posterior cell open, closed or narrowed; face gently or not at all convex, more or less clothed with hair. {Triclis^) (9) . . Laphystia. 16. Antennae elongate, composed of five joints; nearly bare species of considerable size. ........ 17 Antennae less elongate or rather short, the third joint with or without a short or slender style; no spine on upper side of third joint 19 17. First joint of antennae about three times the length of the second, third elongate, fourth and fifth of nearly equal length; third and fourth at their tip with two lobes or processes reaching to about the middle of the following joint (11). Myelaphus. Third and fourth antennal joints not lobed at tip. . . 18 18. First and second joints of antennae of nearly equal length, the third elongate, fourth short, fifth elongate and densely pubes- cent (10) Ceraturg-us. First four joints of antennae as in preceding, the fifth oval, with a short lateral spine. . . ... . Ceraturg-opsis. 19. Style of antennae short, thick, obtuse, not easily distinguishable from the third joint, or, if so, forming apparent antennal joints; antennae more or less elongate. ..... 20 Terminal style of the antennae more slender than the third joint, divergent or easily distinguishable; antennae usually shorter. 22 20. Nearly bare species; face flattened, bare, save below. Small or rather small species, for the most part shining or metallic black, with narrow or cylindrical abdomen and large wings. . 21 * If thorax and abdomen yellow and black, withoiit pollinose cross- bands, the wings conspicuously orange-colored and blackish, Cacodcs- nion [Prolepsis) S. A. t The so-called species of Triclis and Laphystia are very variable, and I doubt their generic distinction, notwithstanding the open or closed first posterior cell. 200 NORTH AMERICAN DIPTERA. More pilose species, the bristles few and hair-like; antennae springing from a convexity, the facial profile thence receding to the tubercle, which is situated low down; abdomen short, head rather narrow Dicolonus. 21. All the tibiae and the hind femora with short, strong setae. Echthodopa. Hind femora, at least, without such setae (12). . Dioctria. 22. Abdomen slender; front broad anteriorly, very narrow behind, the ocelli far forward. Plesioma. Front not narrowed behind. ....'.. 23 23. Face distinctly swollen in profile, gibbous. . • . 24 Face flattened, or gently convex. . . . . . . 25 24. Rather or quite thickly pilose; the gibbosity of the face reaches to the base of the antennae; anal cell usually open. Oyrtopog'On. Thinly pilose, more pollinose species; the convexity of the face is confined to the lower part; anal cell usually closed. Lasiopogon. 25. Hind tibiae distally and the hind metatarsi much thickened. 26 Hind tibiae not or but slightly thickened distally; hind metatarsi not enlarged. ......... 27 26. Head much broader than high, transverse, goggle-like in appear- ance; abdomen short; wings large (compare MetapOi(Oii) (36) . Holcocephala. Head only moderately broader than high, not at all spectacle-like in appearance. ....... Holopogon. 27. Abdomen with thick, recumbent pile above; thickly pilose spe- cies; antennae slender. . . . . . Pycnopogon. Abdomen not with such pile above. ..... 28 28. Slender, nearly bare species; face perpendicular, straight or gently concave in profile, narrowed above, and bare, except on oral margin. .......... 29 Face gently rounded, not prominent below, in large part hairy, and but slightly or not narrowed above. ... 30 29. Thickly whitish pollinose ; abdomen flattened, usually reflected upward; third joint of antennae and the style both slender. Stichopogon. Less thickly pollinose; abdomen cylindrical, a little broader at the base; third joint of antennae short and broad, the style minute. "Habropogon". ASIIvID^. 20I 30. Large, elongate species, the style of antennae short. Callinicus. Moderately large, not markedly elongate species. . , 31 31. Abdomen broader at base, depressed; thorax often strongly con- vex above, antennae slender, the style long and slender (com- pare also species of Cyrtopogon and Metapog07i) . Heteropogon. Abdomen short, cylindrical; black, with bright golden, opaque poUinose markings on thorax and abdomen (39) . Chrysoceria. 32. Face bare, with bristles on oral margin, in profile straight or gen- tly concave, the oral margin most prominent. . • . 33 Face convex below, the oral margin not the most prominent, more or less covered with hair. ....... 35 33. Fourth posterior cell closed a considerable distance before the margin of the wing; antennae without style. ... 34 Fourth posterior cell open or closed in the margin. Saropogon. 34. Posterior pulvilli much shorter than the elongated claws; abdomen contracted toward the base (13)^. . . Blepharepium. Posterior pulvilli not much shorter than the claws; abdomen not contracted toward the base t (14,15). . . Deromyia. 35. Third joint of the antennae more or less dilated, the style very short (16). Lestomyia. Third joint of antennae slender, elongate 36 36. Head broad and flat, the face not gibbous, .... 37 Face convex, densely covered with hair; thickly hairy species. Lastaurus. 37. Third joint of the antennae with an excision on the upper border before the tip, bearing a small spine; abdomen punctulate (17, 18) {Dioctrodes Coq.) Taracticus.J Third antennal joint with a small terminal style; abdomen smooth, not punctulate. ......... 38 38. Abdomen flattened, in the male a little broader beyond the mid- dle; in the male near the tip, the last two segments conspicu- ously silvery above (20). ..... Nicocles. Abdomen of male not flattened and silvery distally (19) . Cophura. * If abdomen not contracted toward the base, the scutellum with bristles, Allopogon^ S. Amer. t If abdomen contracted toward the base, the scutellum without bristles Se no basis {Lochites), S. Amer. X T. vitripennis and T. niger^ with a large two-jointed style, and without lateral spine, must be separated generically. 20 202 NORTH AMERICAN DIPTERA. LAPHRIN^. Marginal cell closed, antenme ivit/t or ivithouf a terminal style, not with a terminal bristle. 1. Front tibiae with a terminal, claw-like Spur 2 Front tibiae not with such spur 3 2. Thorax projecting prominently in front (21, 41). Pseudorus. Thorax not projecting prominently in front* . Doryclus. 3. Veins at distal ends of the discal and fourth posterior cells paral- lel or continuous in the same straight line. ... 4 Veins at distal ends of discal and fourth posterior cells very dis- tinctly angulated and not parallel 7 4. Third joint of antennae with a terminal style, in length greater than the first two together; eyes not or but slightly emarginated on the sides of the front, the front much wider above; scutellum without bristles, or with hairs; small species (42) . Atonia. Third antennal joint without terminal style. ... 5 5. Third joint of antennae at least three times as long as the first two together; rather large species. . , . . Aphestia. Third antennal joint not more than twice the length of the first two combined; small species. ...... 6 6. First antennal joint more than twice the length of the second; front much widened above, the eyes disciform and with enlarged fa- cets in front; scutellum with weak bristles ; body punctulate (44) Cerotainia. Third joint of antennae not more than twice the length of the sec- ond; eyes on the sides of the front emarginate, the front not widened above; scutellum with bristles; first posterior cell usu- ally narrowed; body punctulate (22, 43) . . Atomosia. 7. Three submarginal cells present; first posterior cell closed or nar- rowed (23). Pogonosoma. Two submarginal cells. ........ 8 8. Antennae with a distinct terminal style. .... 9 Antennae not with a terminal style. . . . . .10 9. Rather small, nearly bare species, with pollinose spots or fasciae on the abdomen; first posterior cell open or closed (see Dasypo- goninae, 16; Laphystia.') * The distinction between these two genera seems doubtful to me. Megapoda is a distinct genus, characterized by the hind tibiae and metatarsi not being thickened; the name is not preoccupied. ASILID^. 203 Very large, robust, thickly hairy species, first posterior cell nar- row throughout; hind femora of nearly equal thickness through out [Hyper echia) 24 Dasylechia. 10. Densely pilose, large species, the abdomen short and broad, usu- ally broader beyond the middle (25) . . . . Dasyllis. More elongate, less hairy or nearly bare species, the abdomen not distinctly broader beyond the middle. . . . .11 11. Body nearly bare; hind femora usually with spinous tubercles be- low; species of rather moderate size (45) . . . Lampria. Body more or less hairy, from rather small to large size; first pos- terior cell often narrowed or closed [Nitsa] ; hind femora not with spinous tubercles below (26, 46) . . . Laphria. ASILIN^. ^!(iir]in(tl cell closed; antenna' ahraijs irith a long terminal arista. (32.) 1. Bristle of antennae pectinate below (27) . . . Ommatius. Bristle of antennae bare. ........ 2 2. The veins closing the discal and fourth posterior cell in the same straight line or parallel. • . . . . Atractia. The veins closing the discal and fourth posterior cells not parallel. 3 3. The posterior branch of the third vein curves forward to meet the costa at or before the tip of the wing; or the anterior branch of the third vein angulated near its origin, with stump, or both, 4 The posterior branch of third vein terminates be5-ond the tip of the wing; the anterior branch witliout stump. .... 6 4. Ovipositor cylindrical, with a terminal circlet of spines. . 5 Ovipositor laterally compressed, without terminal circlet of spines (fig. 74) . . • Erax. 5. Abdomen shorter than the wings (28) . . . . Eccritosia. Abdomen longer than the wings (28) . . . Proctacanthus. 6. Two submarginal cells. ....... Asilus.* Three submarginal cells. ........ 7 7. Abdomen shorter than the wings; body thickly pilose; claws obtuse (29) Mallophora, Abdomen longer than the wings; body thinly pilose; claws more pointed (30,31,32). Promachus. * In general the subdi\'isions of the old genus Asihis ixre very vague 204 NORTH AMERICAN DIPTERA. SUBGENERA OF ASII.US. a. Ovipositor laterally compressed. ..... b Ovipositor conical. ........ h b. Third antennal joint unusually hairy*. . Anarmostus. Third antennal joint not unusually hairy. . . . . c c. Face without gibbosity, narrow throughout, not at all carinate, the mystax composed of a few long hairs. Senoprosopis. Face with gibbosity, or not unusually narrow. . . • d d. Posterior border of the last ventral segment in the male more or less widened Machimus. Posterior border of the last ventral segment of the male not un- usually widened. ........ e e. I/Cgs prevailing shining yellow in color. Heligrnoneura. IvCgs prevailingly black, or light and opaque colored. . f f. Abdomen shining black above and below. Stilpnogaster. Abdomen not shining black above and below. . . . g g. Male genitalia club-like Neoitanius. Male genitalia not club-like; the sixth and seventh segments take no part in the formation of the female ovipositor. Tolmerus. h. Abdominal segments with bristles before the incisures. Philonicus.t Abdominal segments not with bristles before the incisures, i i. Bright-colored, larger species. ..... Asilus. Small, ashy gray species Rhadiurgus. and hard to define, and many of them are doubtfully entitled to recog- nition. At the most, few if any of them are based upon real generic characters, and the names are only useful as aids in the determination of the numerous forms. The groups Epitriptus, Lophonotus and Neoeristicus have also been reported from Central America by Bellardi and Bigot, but there is doubt as to their correct reference. * The only reported species of Anarmostus is from Brazil and Brit- ish Honduras. It has the abdomen deep steel blue and black, the wings deep steel blue (i6 mm.) t Ivoew. lyinn. Ent. 144; Philodiciis Loew, Dipt. f. S. Afr. p. 144. XXII. FAMII.Y THEREVID^. ^^b- .79' Thereva senex^ enlarged. After I^ugger. Rather small or moderate sized, elongate (American forms), bristly, sometimes pilose, predaceous flies. Eyes of the male contiguous or approximated; front in the female not excavated. Antennae composed of three joints, the third simple, with a terminal style, sometimes wanting. Proboscis projecting, the labella broad; palpi two-jointed. Ocelli present. Abdomen elongate, geni- talia moderately or but little prominent. Legs with bris- tles; empodia wanting; pulvilli rarely wanting. Third longitudinal vein of the wings furcate, the posterior branch terminating beyond the tip of the wing; five pos- terior cells, anal cell usually closed toward the margin of the wing. 205 2o6 NORTH AMERICAN DIPTKRA. The family comprises about two hundred known spe- cies, with but few widely distributed genera. The flies resemble the Asilidae somewhat, and have habits not dissimilar, though much less active. The proboscis has fleshy labella, instead of the horny tip of the Asilidse, and the legs are less stout — in many species they are easily broken off when captured. Their food is chiefly other diptera, for which they lie in wait upon leaves and bushes, or upon the bare ground. The larvae have a short, eyeless, nonretractile head, the antennae small and short. The body is slender and snake-like, showing ap- parently nineteen segments. Anterior spiracles situated at the end of the first segment behind the head; poste- rior spiracles on the apparently seventeenth segment. The larvae live in the earth and decomposing w^ood, or in sand, feeding upon other insects or upon vegetable matter, ordure, etc. The pupae are free; they have in front laterally projecting spinous points. The genera of this family are, for the most part, very unsatisfactorily founded. F'ew structural differences ex- ist, save in the antennae and proboscis, and these differ- ences seem usually to have specific value only. Five genera have been proposed for North American species; each contains a single species, and in all probability there never will be any additions to them. On the other hand Thereva and Psilocephala^ with numerous species, are doubtfully distinguished by the vestiture of the face! If the smaller genera are recognized, at least one or two more should be formed for those species of Thereva having a thickened first antennal joint ( T, melayiopheba lyoew, T. crassicornis Bell., T. pachyceras, n.n. for T. crassicornis Will.) The closure or non-closure of the fourth posterior cell occurs in both genera and compli- cates matters. The division of the first posterior cell in THERKVID.^. 207 Metaphragma is, I believe, purely a _ specific character, and will not be found in allied species. Fig. 80. Therevidae. i, Tabuda, head; 2, Psilocephala, wing: 3, Psilocephala, antenna. I. 2. 5- TABLE OF GENERA. First antennal joint much thickened and elongate. . . 2 First antennal joint not noticeably thickened. ... 5 Head not as broad as long; vertical diameter of the eyes equaling the horizontal diameter; eyes of male dichoptic. Nebritus. Head distinctly broader than long. ...... 3 Third antennal joint about one-third the length of the first; fourth posterior cell open. ........ 4 Third antennal joint more or less elongated. . Thereva, pt. First posterior cell divided by a cross-vein. . Metaphragma. First posterior cell not divided by a cross-vein {f Pachyrhiza, ? Baryphora) (1). . • . . . . Tabuda. Third joint of the antennae about four times the length of the first; without style; fourth posterior cell closed; front of male broadly dichoptic Henicomyia. Third joint of antennae not four times the length of the first; fourth posterior cell open or closed. ...... 6 Face bare; usually more bare and shining species (2, 3) {Ozodi- ceromyia) Psilocephala. Face distinctly pubescent or hairy; usually more pilose and polli- nose species. (Fig. 80; also fig. 15, p. 42, not Rhyphus.) Thereva. XXIII. FAMII.Y SCENOPINID^. Flies of moderate or small size; generally black in color and bare. Front not excavated; face bare, short and broad. Antennae approximated at the base, the first two joints short, the third elongated, simple, without style or arista. Proboscis concealed; palpi cylindrical, bristly at the tip. Ocelli present. Males usually holoptic. Thorax rather long, moderately convex, though appar- ently much so from the low position of the head. Scutel- lum broad and short, without spines or tubercles. Ab- domen flattened, or cylindrical, composed of seven segments. Squamae small. Bmpodia wanting. Third longitudinal vein of the wing furcate; basal cells long, the first much longer than the second; three posterior cells, the first narrowed in, or closed before the margin ; anal cell closed. Fig. 81. Scenopinidae. 1, Scenopinus,W\ng\ 2, Sce?20pin2is, head', 3, Metatrichia^ wing; 4, Metatrichia^ head; 5, Pseiidatrichia, wing. The larvae resemble closely those of the Therevidae. They are ver}^ long and slender, having apparently nine- 208 SCKNOPINIT^. 209 teen segments, due to eacb of the abdominal segments except the last being partially divided by a strong con- striction. The larvae have been found in decaying fungi and wood and under carpets or in furniture, and are sup- posed to be carnivorous. The flies are not very active in their habits, and because of the frequency with which some are observed on window-panes are usually called window-flies. TABLE OF GENERA. 1. First posterior cell open (1, 2). . ... • Scenopinus. First posterior cell closed before the margin of the wing. . 2 2. Body short, clothed with scales (3, 4). . . Metatrichia. Body elongate, without scales (5) . . • . • Pseudatrichia. ©i XXIV. FAMII.Y BOMBYLIID^. Fig. 84. Bom bylius major, enlaiTg&d. After \A'ashburn. Rather large to small flies; often with abundant, long and delicate hair, rarely with conspicuous bristles. Head as broad as, or narrower than the thorax, often spheri- cal in shape, closely applied to the thorax. Eyes large, often contiguous above in the male, and rarely also in the female. Antennae porrect, usually of moderate length or quite small; third joint simple; style usually small and indistinct, never more than two-jointed, and some- times wholly indistinguishable. Ocelli present. Probos- cis sometimes short, with broad labella; usually project- ing from the oral cavity, sometimes long and slender. Abdomen composed of from six to eight visible segments, slender in a few genera only. I^egs moderately long and weak, with short, weak bristles or spines. Pulvilli 210 Fig. 82. Oncodocera, a^. (Brazil). Fig. S3. Sysfropus, sp. (Brazil). BOMBYIvIID^. 2 1 1 sometimes rudimentary, the empodia almost always so; tarsi and claws usually small. Squamse small. Wings often with dark markings; two or more submarginal,* three or four, rarely fivef posterior cells present; discal cell present in all our genera (absent in Apolysa, Cyrtosia); anal cell closed in or near the margin, or narrowly open. The family Bombyliidse comprises about fifteen hun- dred known species. Most of them are swift-flying in- sects, often hovering motion- less in the air for a time and darting away like a flash. They seek sunny places in Fig. 85. Exop7-osopa,s^., s, often associated together, present such important structural differences, and the resem- blance of the insects composing them is so slight, that their separation seems entirely proper. Tanypezidce . Head broad, subhemispherical, the occi- put concave, the eyes very large, the posterior orbits very narrow, the cheeks also narrow; front rather narrow, with bristles on upper half only. No vibrissal bristle. Antennae more or less elongated, decumbent. Venation complete; posterior basal cells small; first posterior cell narrowed in the margin. Legs long; tarsi longer than the tibiae; tibiae without preapical bristle. A single genus Tanypeza, with a half dozen species perhaps, is all that can be definitely referred to this group. It will be readily recognized from the accompa- 264 MICROPKZID^— TANYPBZID^. 265 nying figures (9, 10). A second genus, Tet^xidiscus Bigot, may possibly belong here, though it has the first posterior cell open and the third joint of the antennae rounded. The genus, if not identical with some other already known, can not be located until specimens are studied by some competent dipterist. MicropezidcE. Head subsperical; front rather broad, not bristly on the lower part. Eyes relatively small, the orbits and cheeks moderately broad. No oral vibrissse; face retreating in profile, sometimes very much so. Tho- rax narrowed anteriorly. Antennae short or moderately elongated, porrect. Abdomen elongate; male genitalia often large and complicated. Wings elongated; auxil- iary distinct in its whole course; or so closely applied to the short first longitudinal vein as to be distinguishable with difficulty. Anal cell always present, short, or drawn out into an acute point; second basal cell sometimes con- fluent with the discal cell; first posterior cell closed or much narrowed in the margin. Legs long and slender, the tarsi shorter than the tibiae; no preapical tibial bristle. So far as the known European and North"American genera are concerned, the above diagnosis clearly defines the limits of the group. There are numerous forms in South America, however, which seem to break down the limits on the one hand from the Piophilidae, on the other from the^Ortalididae. The narrowing or closure of the first posterior cell is very distinctive of our species, but is not a group character. Nor are the slender legs a real 'family' character, since there are southern forms with thickened hind femora and shorter legs which insensibly connect the more typical CalobatcB or Micropezce, through Cardiacephala, with the Ortalididae. The group is dis- tinctively a South American one. The writer has more than a score of species in his collection from Brazil. 266 ^ORTH AMERICAN DIPTKRA. Fig. 103. Micropezidse, Tanypezidse. i, Nerius bistriatus, wing; 2, Nerius, head; 3, Telostylus, antenna; 4, Calobata mellea, wing; 5, Micropeza, wing; 6, Mic7^opeza antenna; 7, Cardiacephala, head; 8, Cardiacephala, hind leg; 9, Tanypeza claripennis, head; 10, Tajiypeza, wing. TABIvK OF GKNERA. Second basal cell confluent with the discal cell (5, 6) . Micropeza. Second basal cell complete 2 Third antennal joint truncate at the tip, with a terminal bristle (1, 2) Nerius. Third antennal joint tapering to a point, into which is inserted the apical, pubescent arista (3). . Telostylus Bigot. Arista distinctly dorsal, that is nearer the base of the third joint than its tip; wings usually with markings. • • • 3 Auxiliary vein distinct; femora simple (4). . . Calobata. Auxiliary vein indistinguishable; posterior femora with a swelling beyond the middle (7, 8) Cardiacephala. XXXV. Family PSII^ID^. Front bristly on the upper part; broad. Face perpen- dicular or somewhat retreating in profile, without vibris- sse. Antennae moderately or very long, decumbent. Abdomen rather slender; male genitalia but little prom- inent, the ovipositor usually elongate. Wings large; auxiliary vein absent or indistinct; third and fourth longitudinal veins parallel ; all three basal cells distinct. lyCgs elongate; no preapical bristle on the tibiae. The flies of this family are of moderate size and elon- gate. The larvae of those few species in which they are known live in the roots or galls of different plants. The larvae of Psila are slender, cylindrical, pale yellow, bare; the posterior stigmata are small, rounded or button-like processes of a black color. Fig. 104. I, Loxocera; 2, Loxocera, head; 3, Chyliza, wing; 4, Chyliza, head. 267 268 NORTH AMKRICAN DIPTERA. The occurrence of Megamerina Rondani in America lacks confirmation. It has the auxiliary very distinct and probably belongs more properly with the Sepsidse. TABIvB OF GKNKRA. 1. Antennae much elongated, the third joint slender (1, 2) . Loxocera. Antennae shorter than the face, the third joint oval or rounded. 2 2. F^ce nearly perpendicular in profile; anal cell noticeably shorter than the second basal cell (3, 4) . . . . Chyliza. Face retreating in profile; anal cell as long or longer than the sec- ond basal cell Psila. Fig. 105. Sepsidae. i, Sepsis, wing; 2, Sepsis, head; 3, Sepsis, front leg; 4, Prochyliza, head; 5, Piophila, wing; 6, Piophiia, head; 7 Michogaster, head (S. A.); 8, Michogaster, wing. XXXVI. FAMII.Y SEPSID^. Fig. io6. Piophila casei, enlarged. After Washburn. Head rounded; front bristly above; face perpendicular or a little retreating ; border of the mouth more or less hairy, with or without vibrissae ; proboscis short; anten- nae not porrect, usually short. Abdomen usually notice- ably narrowed at the base; hypopygium prominent. Auxiliary vein distinct or more or less coalescent with the first vein; all the basal cells distinct. Middle tibiae with spurs; tibiae usually without preapical bristle. The flies of this family are usually small, black and elongated, with the abdomen narrowed at the base, thick- ened and curved downward toward the extremity; with transparent, irridescent wing, usually hyaline, but often with a spot or spots toward the end, and are usually ob- served about decaying vegetables, excrement, cheese, ham, etc., often in swarms. The flies for the greater part, run about actively and are quick in flight. The best known are the species of Piophila, the larvae of which are 269 270 NORTH AMERICAN DIPTERA. SO well known as 'cheese-mites'. These larvse live in cheese, in ham or bacon, or in general in any fatty ma- terial, and often do much damage, being especially troublesome in pork-packing establishments. From the peculiar power of leaping possessed by the maggots they are often called 'skippers'; the act is performed by the lar- va seizing with its extended mouth-hooklets the edge of the posterior truncature of the body and then suddenly releasing it while pulling hard. The larvse are some- what conical, pointed anteriorly, truncated behind, and about five millimeters in length. They are shining and smooth; the antennae composed of two equally long joints; the mouth booklets separated, short and divergent ; the anterior spiracles whitish, the abdominal legs roughened, the anal segment with four fleshy protuberances. Pupa- rium elliptic, rugose. TABLE OF GENERA. 1. Head depressed; antennae elongate. ..... 2 Head not depressed; antennae not reaching beyond the oral mar- gin 3 2. Second joint of antennae elongate, the third oval (4) . Prochyliza, Second joint of antennae short, the third elongate. Tylomyia^ 3. Auxiliary vein distinct; palpi vestigial 4 Auxiliary vein indistinct, or wanting. ..... 6 4. Abdomen curved, narrowed at base, the second segment swollen. 5 Abdomen straight or but slightly curved, but little narrowed at base, the second segment not swollen, . . Themira, 5. Front femora of male with tubercles on under side (1, 2, 3) . Sepsis. Front femora of male not with tubercles on under side. Nemopoda. 6. Wings with blackish spot at tip; antennae reaching nearly to the oral margin Mycetaulus. Wings wholly hyaline; antennae shorter (5, 6) . . Piophila. XXXVII. Family ORTALIDID^. Fig. 107. Antineura, sp. Brazil. Knlarged. Rather small to moderately large flies. Front broad in both sexes, never with lower fronto-orbital bristles. Vi- brissse wanting. Clypeus distinct, usually well devel- oped; proboscis more or less stout; palpi broad, seldom narrow. Abdomen with five segments in the male, six in the female, the first two in both sexes more or less coalescent; male with a rolled up, long penis; female with a three-jointed, horny ovipositor. Legs usually stout and short, never very slender. Venation of wings complete ; auxiliary vein usually completely separated 271 272 NORTH AMERICAN DIPTKRA. ORTAI^IDID^. 273 Figs. 108, 109. Ortalididse. i, Pyrgota; 2, Sienopterina; 3, Camp- to neiir a ; 4, I dan a ; 5, Rivellia ; 6, Tetariops; 7, Pseudotephritis; 8; Oedopa; 9, Chcstopsis; 10, CcElotnetopia; 11, Pterocalla; 12, Melie- ria; 13, Eufneiopia; 14, Richardia; 15, Euxesta; 16, Euxesta; 17, Notograrnma; 18, Euphara; 19, Antineura; 20, G'^w. «a, wing, head, and front tibiae and tarsus of male. But two genera of this family are known from North America. Species of the genus Coelopa are observed, often in abundance, among sea-weeds thrown up by the waves along the sea-shore. Recently Mr. Coquillett has added another genus, O7nomyia, from California (Ca- nadian Entomologist, 1907, p. 76), differing from Coelopa in having the scutellum nearly one-half as long as the mesonotum, distally subtruncated, bare, and with two pairs of lateral bristles. The habits of the type species (O. hirsiita) are not given. XLIX. Family HETERONEURID^. Head broad, subhemispherical. Face short, nearly vertical; vibrissse present. Front broad, bristly to or nearly to the root of the antennae. Ocellar bristles usu- ally present ; postvertical bristles divergent. Antennae porrect; first two joints short, the third usually rounded; arista bare, pubescent or short plumose. Proboscis short; palpi rather broad. Body more or less elongate. Eegs rather long and slender; tibiae with or without a preapi- cal bristle. Venation complete ; basal cells small; first longitudinal vein short, the auxiliary narrowly sepa- rated from it; sixth vein not reaching the wing margin. The members of this small family of rather small flies are to be found throughout the summer in shady places by the sides of brooks, or in the forests about the trunks of decaying trees; in damp meadowy places among the grass; on leaves, etc. Larvae of this family have been found in decaying wood, under bark of trees, etc. They are slender, cylindrical, slightly thickened posteriorly, white in color. The mouth booklets are very small, the body segments not distinctly separated; abdominal segments with a transverse swell- ing for locomotion. The larvae have the power of leap- ing as have those of Piophila. The act is performed by fixing the mouth booklets in the two chitinous, straight or curved booklets on the upper side of the last segment and then suddenly releasing them. The puparia are yellowish, ellipsoidal and with two horns on the last segment as in the larvae. Mr. Czerny has attempted recently to break up the genus Heteroneura, using for generic characters the bris- tles of the front chiefly. I gravely doubt whether all 318 HKTKRONEURID^. 319 his genera will be found valid eventually. Heteringomyia he diagnoses as differing from Heteroneuj^a in the absence of cruciate bristles (a pair of small bristles toward the middle of the lower part of the front) and the absence of preapical bristle on the tibiae. H. flavipes, lumbalis and valida lack the cruciate bristles, but one of them, {H. lumbalis) has a distinct preapical bristle, so that this character is rendered invalid, or the cruciate bristle char- '^'""■"r,rm7r/jm7rTriil"^fninmnr||itiirir'iir«"'^^' Fig. 127. Heteroneuridae. i, Heteroncura, wing; 2, Heteroiieura^ head from in front showing arrangement of bristles (Czerny); 3, Heteringomyia, head from in front showing arrangement of bristles (Czerny) ; 4, Chcstoclusia, head; 5, Chcz'toclusia, wing; 6, Hetero- neura, head; 7, Cliisia, head (Czerny). 320 NORTH AMERICAN DIPTERA. acter; which I leave for Mr. Czerny to decide. His genus Hendelia he distinguishes from Heteroyieura by the absence of the post-vertical bristles, and the more remote insertion of the antennae from each other. Mr. Coquillett has added another, based chiefly on the absence of both postvertical and cruciate bristles. Still another from South America (fig. 6) differs in the arrangement of these bristles. Possibly such a division of the species is natural, but I am yet to be convinced that it is. I omit the preapical bristle character in the 'table, since that, at least, seems worthless, as was observed long ago by Loew. TABLE OF GENERA. 1. Cross veins approximated, the penultimate section of the fourth vein not more than one fourth the length of the ultimate sec- tion. ........... 2 Cross veins not approximated; the penultimate section of the fourth vein at least one-third the length of the ultimate section (7 and p. 8o, 16.) Clusia. 2. Postvertical, ocellar and cruciate bristles distinct {Chisiodes Coq.) (1, 2) Heteroneura. Post-vertical and ocellar bristles present, the cruciate absent (3) . Hetering-omyia. Postvertical and cruciate bristles absent, the ocellar obsolescent; distal end of first vein bristly (4, 5) . . . Chsetoclusia. For Peratochcetus ornatus, see Geomyzidae {Spilochroa.) L. Family SCIOMYZID^. Fig. 128. Tetanoccra lunbrarujN , enlarged. Head short"^, as broad or broader than the thorax; face more or less retreating ; mouth without Vxbrissae at its border, the margin angular. Abdomen composed of six segments, rather long and narrow. Wings longer than the abdomen; auxiliary vein present, distinctly separated from the first longitudinal vein; posterior basal cell and the anal cell complete. I^egs rather long; preapical tibial bristle present. * The genus Trigononietopiis will be brongbt here by the family table. It has been variously referred to the Heteroneuridae, Scioniy- zidae, Ortalididae, vSaproniyzidae by authors. It will be recognized by itsprojecting head and very retreating face. (30) 321 322 NORTH AMERICAN DIPTKRA. The members of this family are usually found in mead- ows, along the banks of small streams, etc., wherever it is moist. They are, for the most part, brown or brownish yellow in color, oftentimes with pictured wings. They are slow in their habits. The larvae are slender, cylin- drical, thin anteriorly; the last segment with six or eight conical, fleshy tubercles. They are aquatic. Fig. 129. Sciomyzidae. i, Sepedon, wing; 2, Sepedon, hind leg; 3, Sepedon^ head; 4, Tetafiocera, wing; 5, Tetanocera, head; 6, Scio- niyza, wing; 7, Sciomyza, head; S, Thecoinyia, head; 9, Trigonome- topus, head. SCIOMYZID^. , 323 TABIvK OF GKNKRA. 1. Second joint, at least, of antennae short. .... 2 Antennae elongated. ....... . . 8 2. Face excavated, the oral margin protuberant. .... 4 Face retreating in profile, but little or not at all excavated; oral margin but little or not at all prominent. .... 3 3. Head strongly projecting forward (9). . Trig-onometopus. Head not at all projecting (7). . . ... Sciomyza. 4. Cheeks broader than the long diameter of the eyes; oral border moderately protuberant; costa somewhat spinose. Actora.* Cheeks not broader than the long diameter of the eyes; oral margin very prominent; costa bare. ...... 5 5. Clypeus prominent. ......... 6 Clypeus not prominent. . . . . . . . -7 6. Scutellum with four bristles on its border. . Neiiroctena. Scutellum with six bristles (p. 80, 17, 18) . . Heterocheila. 7. Front tibiae with a preapical bristle, . . . Bischofia. Front tibiae without preapical bristle. . . . Dryomyza. 8. Hind femora long; second antennal joint much elongated, longer than the third. ......... 9 Hind femora only moderately elongated and but little thickened; second antennal joint as long or a little shorter than the third (5) Tetanocera. 9. Hind femora thickened; face not produced downward (1, 2, 3). Sepedon. Hind femora not thickened; face much produced downward (8). Thecomyia. * Of doubtful occurrence in North America. 1,1. FAMII.Y HEIvOMYZID^, Fig. 130. Leria pubescens, enlarged. After Washburn. Face nearly vertical, or retreating, with oral vibrissse; front bristly on the posterior half only; antennae short. Abdomen rather broad and long, composed of six seg- ments; male genitalia somewhat prominent. Wings com- paratively large; all the basal cells distinct; costa usu- ally bristly; first longitudinal vein bare. Tibiae with spurs and preapical bristle. The flies of this rather small family are found in grassy, shady and damp places, on windows, etc. They feed upon decaying animal or vegetable substances, fungi, excrement, etc. Many species live in caves and burrows. The larvae of Leria have been bred from bat and rabbit dung; those of Helo^nyza from truffles, decaying wood, etc. They are cylindrical, obtuse behind, more pointed in front; the antennae are situated upon long conical pro- cesses; mouth booklets large and pointed; the seven 324 HEIvOMYZID^. 325 abdominal segments on each side in front widened, below with bristly pseudopods. For Curtonotum^ a genus with pectinate costa, see Dro- sophilidae. Fig. 131. Scoliocentra he/vola, enlarged. TABLE OF GENERA. A humeral bristle present. . . . . . . .2 No humeral, no propleural bristle. .... Helomyza, No bristle above base of front coxae (propleural). Allophyla. A bristle above base of front coxse. ...... 3 Spurs of middle tibiae curved (3 and iig. 131). Scoliocentr^- Spurs of middle tibiae not curved. ...... 4 Face much retreating in profile, the anterior oral border oblit- erated; four dorsocentral bristles present (2). Anorostoma. Face not conspicuously retreating. ,...., 5 326 NORTH AMERICAN DIPTERA. Fig. 132. Helotnyzidse. i, Leria, sp, wing; 3, Anorostonia^ head; 5, Scoliocentra helvola^ middle tibia and tarsus. 5. Eyes very small; four dorsocentral bristles; arista very long. 6 Eyes not very small. .7 6. All the tibiae without bristles on outer side; hind femora of male often emarginate at base below. . Eccoptoraera Loew. Middle tibise at least with bristles on outer side. . Oecothea. 7. Four pairs of dorsocentral bristles. ...... 8 But three pairs of dorsocentral bristles; third antennal joint short; bristles of costa small Tephrochlamys. 8. Costal border of wings noticeably bristly (fig. 130). . Leria. Costal border with very small bristles. . . Heteromyza. 1,11. Family CORDYLURID^. ^^b' 133- Scatophaga furcata, enlarged; after Washburn, Squamae small, the upper one concealing the lower. Head seldom longer than high; eyes rounded or oval, bare, broadly separated by the front in both sexes; front almost always with well-developed bristles. Wings rather large; auxiliary vein always present and dis- tinct; first longitudinal vein never much shortened, where it joins the costa never with bristle; basal cells rather large, always complete; first posterior cell seldom nar- rowed in the border or closed; abdomen with more than four visible segments. Some of the flies of this group are easily confounded with those of the Anthomyidae, but an attentive exam^- ination of the squamae, the number of segments of the abdomen and costa will usually resolve doubt of their correct location. The flies are often of considerable size for Acalypterates, never very small. The family has been called the Scatomyzidae by Becker, who has thoroughly studied and monographed the Ku- 327 328 NORTH AMERICAN DIPTERA. ropean forms. But there is reason in the objection to the use of a term derived from a generic name which is clearly a synonym. The name Cordyluridae, applied by Loew, is the oldest name otherwise, and must take precedence over Scatophagidae, which some authors have used. Many of the new genera erected by Becker have been Fig. 134. Cordyluridse. Scatophaga, male; 2, Acicephala polita, head; 3, Pselaphephila shnilis, head; 4, Or thochcsta {!) gilvipes, head; 5, Spathiophora, sp. head; 6, Parallelomma varipes; 7, Hydromyza confluens, head. recognized in North America within recent years, and doubtless others will be, since the family has received comparatively little study with us. For further study of the group, the reader is advised to procure his paper. I give only such genera in the following table as have been authoritatively recognized from North America, the CORDYLURID^. 329 characters drawn chiefly from Becker's table. Many of the flies, especially those of Scatophaga, are frequently found about excrement; some feed upon other insects which they capture. Many species of Cordylura and their allies are collected in meadowlands and moist places. The larvae of some live in the stems of plants and some, it is said, have been bred from the larvae of Noctua. TABLE OF GKNERA. 1. Prothoracic and stigniatic bristles absent; thorax with five dorso- central bristles, or, if fewer, the palpi broad; at least four scu- tellar bristles present; wings usually long. ... 2 Prothoracic and stigniatic bristles present usually; when absent the thorax usually nearly bristleless; one to three sternopleural bristles present; one to five dorsocentrals, the scutellum with from one to four. ........ 3 2. Moderately large to small species; males more thickly haired than the females; face but little excavated in profile; third antennal joint rounded, with a bare or plumose arista; palpi long and slender; five dorsocentrals present (1, and fig. 133). Scatophaga. Head broad; palpi more or less dilated. ..... 9 3. Front femora on the inner side with a double row of bristles. 13 Front femora at the most with a single row of bristles. . 4 4. Palpi small, slender. ........ 5 Palpi long, flattened, leaf-like; eyes oval; antennae long, the dis- tal end angular; abdomen not noticeably short (3) . Pselaphephila. 5. Palpi with a long, terminal bristle; one sternopleural bristle; arista plumose or strongly pubescent; costa of wings hairy or pectin- ated; third vein straight or gently curved. ... 6 Palpi not with long terminal bristle — one to three sternopleural bristles present. ......... 8 6. Arista plumose; femora and tibiae with strong bristles; five dorso- pleural bristles; usually shining black species. ... 7 Antennal arista slender, scarcely thickened at its base, short or long haired; fetnora and tibiae long and slender, and but little bristly; from one to five dorsocentrals; yellow and black species. Parallelomma . 330 NORTH AMERICx^N DIPTERA. 7. Head noticeably longer than high; face much retreating (2). Acicephala. Head scarcely longer than high; face gently retreating in profile. Cordylura. 8. One sternopleural bristle; eyes but little higher than broad; anten- nae as long as the face; oral margin with but one, anteriorly di- rected principal bristle on each side; arista distinctly haired; five dorsocentrals; moderate sized, shining yellow flies. Megophthalma. Two sternopleural bristles; antennae as long as the face, third joint rounded, strongly pubescent; hind tibiae with two pairs of bris- tles on outer side; shining black, small species. Hexamitocera. Three sternopleural bristles; five dorsocentrals ; arista distinctly hairy ; four scutellar bristles ; hind tibiae with three pairs of bristles; moderate sized, thickly hairy, gray flies. Orthochaeta. 9. Eyes and head round; five dorsocentral bristles. ... 10 Eyes and head oval, higher than long; a single dorsocentral bris- tle; cheeks broad; proboscis thick and swollen; oral border vt'ith one short bristle on each side; antennae short, distally rounded; abdomen flat; hypopygium only a little prominent; rather large; bare, ashy gray flies (7). .' . . . Hydroniyza. 10. Front tibiae on the inner side with a short, rectangular spine in addition to the terminal brisiles. . . Acanthocnema. Front tibiae without such bristle; male hypopygium with long tufts of hairs; third antennal joint somewhat elongated; with a sharp, upper distal angle; oral border with many thickly stand- ing bristles. . Pogonota. Front tibiae without such bristles; male hypopygium without long tufts II 11. Third antennal joint rounded anteriorly; eyes somewhat obliquelj' oval; cheeks small; face very short; oral border with a single bristle on each side; proboscis thickened; legs but little bristly; femora somewhat thickened. . . . Microprosopa. Third antennal joint with a sharp anterior angle. . . 12 12. Acrostical bristles in more than two rows; thorax and legs thickly haired; bristles of oral border numerous; femora strong, with fine hair and weak bristles; cheeks broad (5). Spathiophora. Acrostical bristles in two rows; mesonotum and legs sparsely and not long haired; antennae small, with sharp tip; cheeks not broad; oral border with bristles on each side; small, short, gray-dnsted files {C/io'iosa, Opsiomyia). . Tricopalpus. 13. Under side of head with about ten bristles. . Plethochseta. Under side of head with about four bristles. . Pycnoglossa. LIII. Family ANTHOMYID^. I^'ig* 135- Spilogaster, species; enlarged. Small to moderately large flies, often resembling the common house-fly, usuall}'^ non-metallic in color. Anten- nal arista plumose, pubescent or bare; eyes hairy or bare; males often holoptic, sometimes broadly dichoptic, the females always dichoptic; abdomen composed of four or five segments ; the male genitalia often with subanal ap- pendages; first posterior cell of wings broadly open; bris- tles of body often weak; squamae usually of considera- ble size. 331 332 NORTH AMERICAN DIPTERA. The above definition will, in most cases, distinguish the members of this large family of inconspicuously col- ored flies. Its limits, however, are not sharp; with the true muscids it is connected by Muscina and allied forms; with the Cordyluridse by Fucellia, etc. When one has become tolerably well acquainted with the allied fami- Fig. 136, Anthoniyidae. i, Hyetodesia {Phaonia) hicorum, head, from front; 2, Schcenomyza chrysostonia, head, from in front; 3, C(r- nosia cinerea, head; 4, Lasiops spiniger, wing; 5, Lasiops spiniger; head; 6, Phyllogaster cordyluroides, head; 7, Hotnalomyia {Fajinia) scalaris head; 8, Homalomyia scalaris, wing; 9, Ophyra aenescens, head; 10, Spilogaster, species, head; 11, Spilogaster, wing; 12, Leuco- inelina, species, wing; 13, Leuconielina, antenna; 14, Lispa uHginosa, head; 15, Lispa, species, head from in front; 16, Limophora exul, head. ANTHOMYID^. 333 lies, lie will seldom be much in doubt as to the proper location of his specimens here. The contiguity of the male eyes, together with the open first posterior cell and large squamae, is always decisive. Not a few of the spe- cies are common about houses, outbuildings, etc., and some of them are among the worst enemies to garden vegetables that the agriculturist has to contend against. In the larval stage, the great majority of the species are vegetable feeders, either in living or decaying mate- rial. The larvae of species of Spilogaster, Hydrotcea^ Hy- leTTiyia and Ccenosia have been found in dung or manure; those of Hydrotcea, Ophyra, Aittho^nyia, Honialomyia^ etc., in decaying vegetable material; those of Hylemyia, An- thotnyia, Ho7nalomyia, etc., in the nests of various hymen- optera; those of MydiBa in Sper?nophila and Mirnus. Larvae of various species of Phorbia are very destructive to growing radishes, onions, cabbage, etc., feeding upon the roots. The larvae are either slender and cylindrical, or flat and oval, with four rows of thread-like processes on the segments. Both types are amphipneustic, and are always provided with two chitinous mouth-hooklets. The puparium is oval in the smooth cylindrical forms, flattened in the others. Squama and antisquama, or tegula and antitegula, are the terms proposed by Osten Sacken to indicate respectively the lower and upper scales. TABIvK OF GENKRA. REVISED BY PROF. C. F. ADAMS. 1. Front narrow in the male, not more than one-fifth of the width of the head; often holoptic or subholoptic. .... 2 Front in both sexes wide, including at least one-fourth of the width of the head in the male. . . . . • . . .27 2. Squama larger than the antisquama. " . • . . 3 Squama and antisquama of nearly equal size, neither large. . 17 31 334 NORTH AMERICAN DIPTERA. 3. Proboscis projecting, horny, the labella slender and pointed, turn- ed backward, hook -like; arista pvtbescent; eyes bare; moderate sized, blackish species. . . . . • Drymeia. Proboscis not horny and hook-like. ..... 4 4. Abdomen of male ovate or conical; second segment not longer than the third, the first segment usnally imperceptible. . . 5 Abdomen of male elongate, the second segment longer than the third; first segment usually distinctly visible. ... 12 5. Eyes pilose (1) {Phaonia) Hyetodesia. Eyes bare. 6. Arista plumose. ' . Arista bare or pubescent. 7. Abdomen ovate, not spotted Abdomen subconical, usually s Mydsea. spotted (lO, 11, fig. 135.). Spilogaster. 8. Front femora of the male with tubercles or emarginations below, or otherwise peculiarly constructed; front tibiae often with emarginations; hind femora often arcuate; middle and hind tibiae sometimes with tufts of hairs; black or blue-black flies, often pollinose Hydroteea. Front femora simple in both sexes. ..... 9 9. Abdomen shining black or metallic black (9) . . Ophyra. Abdomen not shining black or metallic, and with markings. 10 10. Vibrissse at some distance above oral margin. Brachyophyra. Vibrissae inserted at oral margin. . . . . . .11 11. Fourth vein nearly or quite straight (16).* . Limnophora. Fourth vein distinctly curved forward (12, 13) . Leucomelina. 12. Eyes pilose Trichophthicus. Eyes bare. . . . . . . . . . -13 13. Anal cell short; axillary vein roundly curved toward it (7, 8). Homalomyla. Anal vein long, often reaching the wing margin. . . 14 14. Arista plumose (28, 29). .... Hydrophoria. Arista bare or pubescent. ....... 15 15. Oral margin and under side of head thickly clothed with bristly hairs Pogonomyia. Not thickly covered. . . . . . . . . 16 * Compare Hammomyia. ANTHOMYID^. 335 Fig- 137- An thorny idse. 17, Pentacricea aldrichi, abdomen; 18, 19, Erevioviyia hii^rieralis, abdomen and head; 20, Dexiopsis lacteipen- nis, head from in front; 21,22, Hamnioniyia unilineatas, wing and head; 23, Caricea insignis, leg; 24, Phorbia brassiccs, abdomen; 25, TetrachcEta unica, head; 26, Hoplogaster nigritarsis, wing; 27, Pogo- myia bicolor, head; 28; 29, Hydrophoria divisa, wing, head; 30, Cho- ristoma pokornyi, wing; 31, Anthomyia radicum, head; 32, Hyleniyia setiventris, head. Dolichoglossa. Anthomyia. Lasiops. 18 19 20 male with- 16. Proboscis slender, nearly as long as the thorax. Proboscis not unusually long (31) 17. Kyes pilose (4, 5). Eyes bare. .... 18. Arista plumose. Arista bare or pubescent. 19. Front prominent, without white spots above antennae; out subanal appendages; female without decussating bristles in front of ocelli; body (except in vittipes) marked with shining black stripes or spots. .... Eustalomyia. Front not prominent; males usually with subanal appendages; fe- male usually with cruciate bristles in front of ocelli; body with- out shining black stripes or spots (32) . . . Hylemyia. 20. Abdomen of male subcylindrical. ...".. 21 Abdomen long, depressed. ....... 25 21. An additional macrochseta above the first posthumeral (18, 19). Eremomyia. Without such macrochaetse, or with a bristly hair instead. . 22 ;36 NORTH AMERICAN DIPTERA. 22. Sides of face and cheeks wide; front of female narrower than either eye; wings without costal spine (21, 22) Hammomyia. Either the sides of the face or the cheeks narrow; front of female often wider than eye; wings usually with costal spine. 23 23. Legs wholly or partly rufous or yellow (27). . Pegomyia. Legs wholly black. ........ 24 24. The anal vein attains the wing margin. . . Chortophila. The anal vein does not reach the wing margin. . . Azelia. 25. The eyes occupy the upper two-thirds of the sides of the head. 26 The eyes do not occupy the upper two-thirds of the sides of the head (24). Phorbia. 26. The anal vein reaches the wing margin. . . Prosalpia. The anal vein does not reach the wing margin. . Coelomyia. 27. Anterior cross- vein situated before the end of the first vein. 28 Anterior cross-vein under or beyond the end of the first vein. 30 28. Wings without costal spine 29 Wings with costal spine (30 ) . . . • • Choristoma. 29. Squamae small, equal Euryomma. Squamae large, the under longer than the upper. Charadrella. 30. Palpi unusually broad at tip (14,15) Lispa. Palpi not unusually enlarged at tip. ..... 31 31. Squamae equal (2) .* , . . . . Schoenomyza. Squamae unequal, the lower projecting beyond the upper. 32 32. Head narrow, antennae not elongate; tibiae with very long bris- tles (23) Caricea. Not having all the above characters. • • • • • 33 33. Four post sutural macrochaetae (25). . . . Tetrachseta. With less than four post sutural macrochaeta. ... 34 34. Five abdominal segments visible (17) . . . Pentacricia. Only four abdominal segments visible. • • • • 35 35. Abdomen cylindrical, incrassate posteriorly; hypopygium prom- inent (6) . {Com^a.re Hoplo^asier Q^Q). Phyllogaster. Abdomen not cylindrical or incrassate behind. ... 36 36. Head much broader than high (20). ... Dexiopsis. Head not markedly broader than high. .... 37 37. Frontal triangle large, with straight sides, the apex blunt, reach- ing the base of the antennae Limnospila. Triangle with concave sides, the apex sharp, seldom reaching the base of the antennae (3) CcBnosia. * Fucellia. The members of this genus, which has been referred to various families of acalyptrates, are found often in abundance along sea-shores, about decomposing material which has been thrown up by the waves. They are of moderate size, blackish gray in color, and will be easily recognized in the males by the hind femora having a bunch of bristles near their base, inserted on a short emargination; the face has numerous vibrissal bristles; the arista is bare, etc. w. 1,1V. FAMII.Y MUSCID^. Fig. 138. Hcematobia serrata^ male; enlarged. Rather small to moderately large, never elongate, thin- ly hairy or bare flies. Antennal arista plumose to the tip; sometimes above only, and rarely bare, in which cases the absence of bristles on the abdomen, except at the tip, together with the narrowed first posterior cell, characters distinctive of the group, will distinguish the flies belonging here from their allies. Byes of the male approximated or contiguous; front of female broad. Eyes bare or hairy. Abdomen composed of four visible segments. Genitalia not prominent. Like the Sarcophagidse, the species and individuals of this family are cominon everywhere. The common house- fly, the type of the group, has a cosmopolitan distribu- 337 338 NORTH AMERICAN DIPTERA. tion wherever man exists. Other species, which are scarcely less common and widely distributed, are the common blue-bottle and blow-flies, members of the gen- era Lucilia and Calliphora. As widely known are the stable -fly or cattle -fly, Stomoxys, and the horn -fly, Hcematobia. The larvae of the house-fly live, for the most part, in dung or manure, but will thrive in almost any kind of filth; I have reared them from the decaying material in the bottoms of spittoons filled with tobacco. The female lays about one hundred and twenty-five eggs, which hatch in one or two days, according to the weather. The larvae attain their full development in from four to seven days, and then, crawling into some secluded place, trans- form into pupae, from which they emerge in about six days as mature insects, those of the autumn broods re- maining over winter as puparia. In partially secluded spots the mature fly will sometimes survive the winter. The cluster-fly, Pollenia rudis, is yet more remarkable in this last respect. Often in early spring, or even during mild days of the winter they may be observed crawling about over the snow in numbers. The}- are stupid and slow and have received the name of cluster-flies from their habit of congregating in clusters about dwellings. They resemble a blow-fly somewhat; but will be distin- guished by the presence of short, depressed, sparse light- colored hairs on the thorax. The larvae of species of Calliphoya, especially of C. vomitoria, are better known, perhaps, than those of any other insect. They are the common blow-fly maggots of fresh and decaying meats and vegetables. The cooking of corned beef or turnips or cabbages during warm weather is sure to attract num- bers of these insects, which are quite noticeable for their loud humming and headlong flight. In the arid regions of northern Wyoming the writer has seen them in extra- MUSCID^. 33^ ordinary numbers, many miles from the nearest human habitation. Either their eggs or the newly hatched larvae are deposited upon meats, and only a day or two is suffi- cient to transform the material into a creeping mass of disgusting maggots. The larvae of species of this genus sometimes have habits similar to those of the screw- worm flies. The blue-bottle and green-bottle flies have habits identical with those of Calliphora, but they are not so common. The screw- worm fly ( Chrysomyia macellaria ) , an insect common over nearly all of North and South America, is bright shining green or golden green in color, but will be distinguished from the blue-bottles by the presence of blackish stripes on the thorax. It depos- its eggs, which hatch almost immediately, in decompos- ing matter, as do other members of the family, but it will also lay them in the ulcers of cattle, or wounds, or at the orifice of the human nose, especially when attracted thereto by a fetid breath. The larvae in these cases quickly penetrate within the nasal and frontal sinuses, sometimes to the number of a hundred or more, quickly producing fever, extended ulceration and in frequent cases, death. These cases of Myiasis, as the affection is called, are not very frequent in North America, but have been not seldom recorded from South America. Sarco- phila Wohlfa/uii, a European species, has similar habits. The group Stomoxyinae includes about thirty known species, all blood-sucking in habit, among which are the notorious stable-flies, horn-flies and tsetse flies. The horn-fly {HcEinatobia sej^'rata^) is a comparatively recent * Speiser, and, following him, Bezzi would call this genus Siphona, a name hitherto applied to a genus of proboscideous Tachinidse, claim- ing that the type was H. serrata {irritans) ; but I quite agree with Austen that the case is by no means proven, and, even if it were, I do not think it calls for such a revolutionary change in these long estab- lished names. 2^o NORTH AMERICAN DIPTERA. introduction from Europe, the first known American specimens having been noticed in eastern Pennsylvania in the spring of 1887; it has now extended over nearly all of North America. An allied species is indigenous to North America, living among the moose of the northern woods. The tsetse flies* are perhaps the most famous of the group. The diseases produced by the microparasites (trypanosomes) transferred into their victims by their elongated piercing proboscis are so dire in their results that the regions certain species inhabit are rendered al- most uninhabitable b}^ the domestic animals. The dis- eases also afflict certain wild animals, though with less fiatal results. The microparasites are, themselves, ap- parently not regenerated in the flies, as is the case with the mosquitoes, but are transferred by them shortly after biting diseased animals to healthy ones. The fatal 'sleeping sickness' (trypanosomiasis) in man is occasion- ed in the same way by the bites of Glossina palpalis. The larvae of Glossina are born when well developed and ready, or about to be ready, to become pupae, resembling those of the Hippoboscidae in this respect. The limits of the Muscidae, both from the Sarcopha- gidae and the Anthomyidae, are quite elusive and uncer- tain; indeed they seem almost impossible of definition save by the aid of artificial and trivial characters. Girschner, and some other authors following him, would unite the Calliphorinae, that is those with hypopleural bristles, with the Sarcophagidse or Tachinidae. The log- ical sequence would be to unite the Muscinae with the Anthomyidae, abandoning the family. His views, how- ever, have not been generally adopted. One genus with bare arista has been generall}^ united with the famil}^ so that the ultimate distinction from the Tachinidae would * An amateur dipterist has recently proposed in all seriousness to separate the tsetse flies into an independent family, the Glossinidae ! MUSCID^. 341 seem to be the lack of hirsuteness of the abdomen. Ou the other hand, there seems to be no real distinction from the Anthomyidse, unless the almost evanescent curvature of the fourth vein be considered as such. Fig. 139. Muscidae. i, Chrysomyia; 2, 3, Pollenia; 4, Mesembri- nella; 5, Graphovnyia; 6, Myiospila; 7, 8, Morel Ha; 9, Muscina; 10, Cliuopera. 242 NORTH AMERICAN DIPTKRA. The larvae of Muscina have been found in deca3ang vegetables, dung, fungi and the larvae of various lepi- doptera, a remarkable diversity of habits. The larvae of G^'aphomyia and Mesembrina have been found in horse and cow dung. TABLK OF GENERA. 1. Proboscis long, slender, directed forward; arista pectinate, or sometimes with a few hairs below also. .... 2 Proboscis not elongate, the labella fleshy and not adapted for piercing. ..-....•.. 3 2. Palpi nearly as long as the proboscis {Lyperosia; fig. 146) . Hsematobia. Palpi much shorter than the proboscis. . . . Stomoxys. 3. Arista bare; distal section of the fourth vein broadly curved at its end . . . Synthesiomyia. Arista pectinate Hemichlora. Arista plumose. ......... 4 4. Hypopleurse with a vertical row of bristles 5 Hypopleurse not with a row or tuft of bristles. ... 14 5. Eyes pubescent Tyreomma. Eyes bare. 6 6. Vibrissal angle at a considerable distance above the oral margin; angle of fourth vein rounded or rectangular. ... 7 Vibrissal angle near oral margin. ...... 8 7. Thorax and abdomen with depressed hairs or tomentum among the bristles, especially noticeable in the intraalar region; dark- colored, slow moving 'cluster flies' (2, 3) . Pollenia. Thorax and abdomen not with such hairs; mesonotum distinctly striped; bright metallic flies (1) . . . Chrysomyia. 8. Bend of fourth vein angular, or with the angle slightly rounded. 9 Distal section of fourth vein with a broad curve ; cheeks bare ; rather large flies, reddish or yellowish, with the distal portion of the abdomen metallic (4) . . . . Mesembrinella. 6. Dorsocentral bristles present. ...... 10 Dorsocentral bristles absent. . . . Ghloroprocta. 10. Arista .usually plumose for not more than two-thirds its length; hypopygium prominent Oynomyia. Arista plumose to tip; hypopygium not prominent. . . 11 11. Mesonotum not flattened behind the transverse suture. . 12 Mesonotum flattened behind the transverse suture. . . 13 MUSCID^. 343 12. Posterior dorsocentral and acrostical bristles well-developed and constant; cheeks hairy; third longitudinal vein spinulose at base only, Calliphora. Posterior dorsocentral and acrostical bristles constant and well- developed; cheeks bare; first section of the third vein for a part or all its length spinulose. ..... Lucilia. 13. Posterior dorsocentral and acrostical bristles inconstant and une- qually developed; cheeks hairy; first section of third vein in large part spinulose. ...... Phormia. Posterior dorsocentral well, the acrostical bristles unequally de- veloped, cheeks hairy; first section of third vein in large part spinulose. . . . • , . . Protocalliphora. 14. Middle tibiae with a prominent bristle on its inner, flexor surface beyond the middle. ........ 15 Middle tibiae without such bristle. ..... 17 15. Termination of first longitudinal vein nearly opposite the middle of the penultimate section of the fourth vein; distal section of the latter forming a broad curve. . . Mesembrina. Termination of first vein nearly opposite the anterior cross-vein. 16 16. Sternopleurae with one bristle in front and two behind; angle of fourth vein rounded. .... Pseudopyrellia. Sternopleuraae with one bristle in front and three behind; last sec- tion of fourth vein forming a broad, gentle curve. Pyrellia. 17. The last section of the fourth vein has a rounded angle; sterno- pleurae with one bristle in front and two behind; never metallic species Musca. Last section of fourth vein broadly curved near its middle, or with an anterior flection at its tip. ...... 18 18. Eyes pubescent. . . . . . . . . . 19 Eyes bare. .......... 20 19. Antennae separated at their base by a distinct carina; sternopleu- rae with two bristles behind, none in front; body gray or partly rufous with a well-defined black pattern (5). Grraphomsria. Antennae not separated at base by carina; sternopleurae with two bristles in front and two behind; body not metallic colored. Myiospila. 20. I^ast section of fourth vein with a broad curvature near its middle. the cell opening rather narrowly; grayish or metallic spotted species (7,8) Morellia. I^ast section of fourth vein curved forward, often slightly, beyond its middle or at the tip, the cell broadly open. . . 21 21. First longitudinal vein ends beyond the middle of the wing; one or more well-developed pairs of anterior acrostical bristles (9) . Muscina. The first vein ends before the middle of the wing; no anterior acrostical bristles (10) . . • . . . Clinopera. So mo my id, Cyrtoneurina and Hyadesimyia are not included in the table, because of insufficient data. I,V. FAMII.Y CESTRID^. ^^j.i.jmjba»-Bjiijs^^j5 Fig. 140. Cuterebra biiccata, enlarged; after Washburn. Flies of moderate to large size, thick-set, usually more or less pilose. Head large, the lower part more or less swollen. Antennae short, three-jointed, decumbent, and more or less sunken in the facial groove or grooves ; arista bare or plumose. Mouth opening small, the mouth-parts sometimes rudimentary, never large. Front broad in both sexes, in the male broader in front. Eyes comparatively small, bare. Ocelli present. Thorax ro- bust, with a distinct transverse suture. Abdomen short, conical or but little elongated; genitalia of the male hid- den, the ovipositor sometimes elongated. Squamge usu- ally large; sometimes small. Venation of the wings muscid-like, in most cases the first posterior cell narrow- ed or closed; anal cell small, sometimes indistinct; discal cell sometimes absent. This family, though of small size comparatively, is of the greatest fnterest by reason of the habits of the larvae, all of which that are known being parasitic upon mam- mals. The adult flies often have vestigial mouth-parts, 344 CESTRID^. 345 and devote the whole of their brief existence to the labors of procreation. Only about seventy-five species are known, and they are generally called bot-flies, though the name is frequently applied especially to the bot-fly of the horse. Parasitism occurs in three principal ways: in the stomach and digestive tubes, in tumors formed by the larvae under the skin, and in the pharyngeal and nasal cavities. With but few exceptions each species is confined to a single species of mammal, and each genus or each group of allied species is parasitic in the same way upon allied animals. Seven species of Gastrophilus are found in the stomach and intestines of the horse and ass. Thirteen species of Hypoder^na are known to live under the skin of the horse, the ox, the buffalo, the sheep, the goat, four species of antelope, and the musk-deer. Two species of CEstromyia likewise infest the skin of La- gomys and HypodcBus. CEdafnageita tarandi is parasitic in great numbers in the skin of the reindeer in both Siberia and boreal America. Four or five species of CEstrus live in the nasal sinuses of sheep, antelope, and horse {Rhin- cestrus). One species of Cephalomyia lives in the nasal cavities and throat of the camel and buffalo. Six or seven species of Cephenomyia have been found parasitic in the pharyngeal cavities of various Cervids, while va- rious species of Cuterebra, Bogeria and Rogenhofera have been bred from the skin or scrotum of rodents and opossums. Two species of Dermatobia have been obtain- ed from the skin of dogs, cattle, cats, deer, and probably apes and man. The eggs or young larvae are, it is be- lieved, in all cases taken into the mouth by the animals which they infest, going thence to the sinuses, pharynx or stomach; or, through the tissues of the body, to the skin. Perhaps those living within the scrotum may reach their abiding place by a more direct route. 32 346 NORTH AMERICAN DIPTERA. ;,:;;;;-; ;,:.>,;yi||p^ Fig 141. CEstridse. i, Gastrophiliis, wing; 2, Gastrophiius, anten- nae; 3, Cuterebra^ antennae; 4, Cuterebra, front tarsus; 5, Cuterebra, wing; 6, Dermatobia, wing; 7, Dermatobia, front tarsus. TABLES OF GENERA. IMAGINES. Mouth-parts very small, vestigial; arista bare. ... 2 Proboscis geniculate, inserted in a deep slit; female without extri- cate ovipositor; first posterior cell narrowed or closed; arista bare or plumose; facial grooves approximated below, enclosing a narrow median groove or depressed surface; squamae large. 6 The fourth longitudinal vein runs straight toward the border of the wing, i. e. the apical cross-vein is obsolete, and the first poste- rior cell is not narrowed; squamae small; female ovipositor elon- gate; larvae in stomach and intestinal canal (1, 2). Gastrophilus. The fourth vein turns forward to form the apical cross- vein, closing or narrowing the first posterior cell. ..... 3 Facial grooves approximated below, leaving a narrow median groove or depression. ...;.... 4 ceSTRID^. 347 Facial grooves remote, enclosing between them a broad, gently- arcuate, shield-shaped surface ; squamae large; female with elongate ovipositor; larvae hypodermatic. ... 5 4. First posterior cell closed and petiolate; body nearly bare. CEstrus First posterior cell narrowly open; body pilose. Oephenomyia. 5. Palpi wanting Hypoderma. Palpi small, globular CEdainag'ena. 6. Arista bare, short and stout; wings without stump at angle of fourth vein. ........ Bogeria. Arista pectinate above. ........ 7 7. Tarsi broad and flattened, hirsute (3, 4, 5); alulae large. Cuterebra. Tarsi slender, not hirsute; third joint of antennae more elongate; front prominent anteriorly; alulae of moderate size (6, 7) . Dermatobia. 1. Last abdominal segment free, broadly attached. ... 2 Ivast abdominal segment (twelfth) retractile within the preceding, small and distinctly constricted. ..... 7 2. Ivarvse with two pairs of chitinized jaws; that is with two outer mouth-hooklets, and two inner, straight, triangular points (Horses) Gastrophilus. I/arvae with two or no mouth-hooklets, ..... 3 3. lyarvae on the median segments with dorsal, spindle-shaped tuber- cles; one pair of mouth-hooklets present. . . • . 4 Larvae without such tubercles; one pair or no mouth-hooklets pres- ent 5 4. Antennae broadly separated; body oval, strongly convex above, flat below (Sheep) Oestrus. Antennae approximated or contiguous; body elongated, somewhat broader in front than behind (Deer) . . Oephenomyia. 5. No mouth-hooklets. ......... 6 Two small mouth-hooklets present (Rodents). Oestromyia, 6. Bristly covering alike above and below (Reindeer) . Oedamagena. Bristles stronger below than above (Ox, etc.) Hypoderma. 7. Larvae oval (Rodents, Marsupials) .... Cuterebra. Larvae club-shaped, more slender posteriorly (Artiodactyls, Carni- vora. Primates). Dermatobia LVI. FAMII.Y SARCOPHAGID^. Fig. 142. Sarcophaga saracenia, enlarged. After Washburn. Usually thick-set, moderately large to rather small flies. Front in both sexes broad, though usually some- what narrower in the male. Arista of the antennae plu- mose to the middle or a little beyond, the distal portion bare; this last character alone is the ultimate distinctive one of the group. Abdomen composed of four visible segments, with the macrochsetse usually confined to the distal portion, though sometimes occurring on the mar- gin of the second and following segments and very rarely on the disk; male hypogygium often prominent. First posterior cell of the wings always much narrowed or closed. 34« SARCOPHAGID.^. ^^^ This family of flesh-flies, as they are often called, though comprising but comparatively few genera, has a great number of species and individuals. For the most part the species are tolerably uniform in coloration, and at first sight seem scarcely distinguishable, having a gray striped thorax and marmorate abdomen. The more metallic colored species of CynoTuyia and Onesia are ex- ceptions. The flies are found everywhere, about decay- ing vegetation, especially fruit, excrement, decomposing carcasses, etc. The larvae are polyphagous in habit, feeding upon de- caying animal or vegetable matter, or living parasitically in the flesh of different animals, in the nasal cavities of man and other animals, in ulcers, etc. The larvae of Cynomyia live in great numbers in the decomposing car- casses of vertebrate animals. The larvae of Sarcophaga, which are often extruded by the parent fly alive, have been found under the skin of turtles, in the stomachs of frogs; and most of the cases of myiasis that have been reported, other than those due to the larvae of Chrysomyia and Calliphoi^a, have been caused b}^ the maggots of the species of this genus and those of Sarcophila. The larvae of several species have been found in snails, in beetles, grasshoppers, the pupae of moths, etc. The Sarcophaga larvae are rounded, thinner anteriorly and amphipneustic. The antennae are short, thick, cy- lindrical, divergent, wart-like tubercles, each with two ocellus-like chitinous rings at the tip. The mouth-hook- lets are distinct, strongly curved, and separated from each other. The abdominal segments are distinctly dif- ferentiated by transverse swellings, and are each pro- vided with a girdle of spines. ^The hind stigma-plate is situated in a deep cavity, which is formed by the last segment alone. The anal swelling is two-pointed. The puparium is oval. 350 NORTH AMERICAN DIPTERA. ^ f'-i Ik V m Fig. 143. Peckia prceceps, enlarged. TABLE OF GENERA. 1. First posterior cell closed or much narrowed in the margin. 2 First posterior cell open. ....... 5 2. Second and third abdominal segments with discal and marginal macrochaetse, Paramintho. Second and third segments without discal macrochaetse. . 3 3. First vein bristly. ....... Johnsonia. First vein bare. ......... 4 4. Arista bare or pubescent. .... Hesperomyia. Arista distinctly plumose. . . . . Sarcophilodes. 5. Abdomen black or metallic, unicolorous and but slightly pruinose. 6 Abdomen gray or partly ochraceous, with black reflecting spots. 8 6. Hypopygium very prominent; legs more or less hairy, . 7 Hypopygium concealed; legs not hairy; curvature of fourth vein with an obtuse angle and without stump. . . Onesia. 7. Abdomen usually black; tibiae densely hairy. . . Peckia. Abdomen metallic; tibiae with short hairs (see Muscidae). Cynomyia. SARCOPHAGID^. 351 8. All the tibiae with a comb-like row of long stout bristles externally. Theria. Without such bristles, or with irregularly placed ones. . 9 9. Cheeks with long bristly hairs below. . . . . .10 Cheeks with short pile. . . . . . Erythrandra. 10. I^ast section of fourth vein more oblique than the posterior cross- vein. ........... II Both veins in nearly the same straight line; two orbital bristles in the female; none in the male. . . . Sarcophaga. 11. Two orbital bristles in each sex. . . . Sarcophagula. Two orbital bristles in the female, male ? . . Helicobia. Sarcodexia and Sarothrofnyia are not included in the table for lack of sufficient data. IvVII. FAMII.Y DHXIID^. Rather small to large, chsetophorous flies, thinly or not at all pilose, usually more elongate than the Tachi- nidse. Eyes of the male contiguous, or more approx- imated than those of the female; pubescent or bare. Front with a row of bristles on each side descending to, but not below, the base of the antennae, save rarely. First joint of antennae short; second usually shorter than the third; third joint more or less elongate, sometimes short, decumbent. Arista bare, pubescent or pilcse, with two or three visible joints. Face always with a well- marked median depression, with a more or less distinct median ridge or carina. Proboscis sometimes elongate, but usually short and with broad labella; palpi never with more than one joint, which is sometimes vestigial. Ocelli present. Abdomen composed of four or five visi- ble segments, with marginal, lateral, and usually discal bristles. I^egs sometimes rather stout; usually elongate and slender; always bristly. All veins of wings simple; basal cells large; three posterior cells present, the first of which is always narrowed or closed; auxiliary vein distinct in its whole length. Squamae large. In habits and life histories, the Dexiidae closely resem- ble the Tachinidae, and the distinction between the two families is very difficult to make, if it is not actually evanescent. The plumose or distinctly pubescent arista, the presence of bristles on the dorsum of the abdomen, together with the usually more slender legs, are the es- sential diagnostic characters of the family. For further study the reader is referred to the works of Brauer, Ber- genstamm, Coquillett, Townsend and Wulp. 352 Fig. 144. Dexia, species. Enlarged. ,X Fig. 145. Scotiptera Melaleuca. Enlarged. \^ R A^>^ Fig. 146. ])exiidae. 1, 2, Scotipf.era melaleuca, wing, head; o, 4, Hi/stn'cod- dexla vfederi, wing, liead; 5, Ch^tona, sp. wing; 6,7, Lejitopoda f/racih's, wing, head; 8, 9, Ca/odexia, wing, liead; 10, 11, Ptilodexia tibialis, wing, head; 12, 13, M i/iocera, sp. wing, head; 14, 15, Rhjinchodexia, sp. wing, head; 10, 17, C/io/oiitijid ni(/riceps, head, legs; 18, Morinia, liead; 19, RhijncJiodexia, head; 20, TJu'laifd /onyirornis, head; 2\,Eii((nt/(ri, sp. wing; 22, Melattophora roralis, wing. 354 NORTH AMERICAN DIPTKRA. TABIvK OF GBNKRA. BY PROF. C. F. ADAMS. 1. Proboscis elongate; slender, not retractile, usually as long or longer than the dorso-ventral diameter of the head. ... 2 Proboscis shorter than the head, thick and retractile. . . 15 2. Proboscis slender and rigid, nearly or quite as long as the head and thorax together; labella small 3 Proboscis as long as or but little longer than the head. . 8 3. Scutellum and abdomen armed with spines. . Hystrisiphona. Scutellum and abdomen with the usual macrochsetse. . . 4 4. Sides of face bare. ......... 5 Sides of face clothed with short bristles. • . Prorhynchops. 5. Palpi very short, thickened at tip; macrochsetse only marginal. Prosena. Palpi moderately long, not at all or but little thickened at tip; macrochsetse usually discal and marginal 6 6. Claws of male extraordinarily long. i. . Mochlosoma. Claws of both sexes short. ....... 7 7. Facial carina broad, inflated, depressed. . . Myiomima. Facial carina narrow, not inflated, compressed. Prosenoides. 8. Abdomen densely covered with macrochsetse. ... 9 Abdomen with regularly arranged macrochsetse. ... 10 9. Vibrissse inserted some distance above oral margin (3, 4) . Hy stric odexia . Vibrissse inserted on oral margin. . . . Bathydexia. 10. Eyes descending not more than two-thirds the distance to lateral oral margin. . . . ' . • • ■ .11 Byes descending at least three-fourths the distance to lateral margin. . . . . . • • • • -14 11. Fourth vein with a stump at its bend (1, 2). . Scotiptera. Fourth vein without stun. p at its bend 12 12. Macrochsetse of abdomen discal and marginal. . . -13 Macrochsetse only marginal (12, 13). . . Myiocera. 13. Face quite concave in profile; vibrissse at oral margin. Myioscotiptera. Face nearly perpendicular; vibrissse some distance above oral mar- gin (14, 15, 19.) Rhynchodexia DKXIID^, 355 14. Facial ridges parallel; antennae inserted on line drawn through middle of eyes Tromodexia. Facial ridges divergent below; antennae inserted somewhat below middle of eyes (Tachinidae, 112) . . . Stomatodexia. 15. Kyes descending less than or hardly more than two-thirds the dis- tance to lateral oral margin 16 Byes descending nearly to lateral oral margin. ... 40 16. Apical cell petiolate or closed in the margin. . . . 17 Apical cell open. 21 17. Posterior cross-vein nearer to bend of fourth vein than to the ante- rior cross-vein, or in the middle. ..... 18 Posterior cross-vein nearer to anterior cross-vein than to bend. 20 18. Fourth vein with stump at bend Megerlea. Fourth vein without stump 19 19. Third antennal joint scarcely longer than second; cheeks without long, bristly hairs below Megaparia. Third joint more than twice as long as second; cheeks with long bristly hairs below. ..... Melanodexia. 20. Sides of face narrow, bare (22). . . , Melanophora. Sides of face broad, bristly. . . ... Microchsetina. 21. Face distinctly carinate. . . . . . . . 22 Face not carinate or but slightly so. ..... 28 22. Antennae nearly as long as the face. . . . Camarona. Antennae much shorter than the face. .... 23 23. Abdomen wide and stout; short; oval, the first segment somewhat shortened. .......... 25 Abdomen conical or elongate oval. 24 Gymnodexia. Dexia. 26 Trixodes. 24. Sides of face bristly above. Sides of face wholly bare (fig. 144). 25. Sides of face bare. . . . Sides of face hairy. 26. Abdomen with discal and marginal macrochaetae. . . 27 Abdomen without discal macrochaetae. . . Ateloglossa. 27. Arista bare or pubescent Megaprosopus. Arista long plumose. ...... Phorostoma. 28. Antennae inserted at or above the middle of the eyes. . 29 Antennae inserted below middle of eyes. .... 32 356 NORTH AMERICAN DIPTERA. 29. Arista short-haired; posterior cross-vein half way betvt-een bend of fourth vein and the anterior cross-vein. .... 30 Arista distinctly plumose; posterior cross-vein near bend of fourth vein 31 30. Eyes bare Acronacantha. Eyes hairy Morphomyia. 31. Antennae not reaching middle of face. . . Phasiops. Antennae reaching at least two-thirds the distance to oral margin^ Metadexia. 32. Eyes small, less in diameter than the width of cheeks. Macrometopa. Eyes of greater diameter than width of cheeks. • • • 33 33. Costa of wings bristly, or at least with a costal spine. . . 34 Costa without bristles or spine. ...... 36 34. Abdomen elongate, nearly cylindrical, twice as long as the thorax; segments of equal length. .... Stenodexia. Abdomen short, stout, the first segment somewhat shortened. 35 35. Sides of face hairy; claws of male elongate (10) . Ptilodexia. Sides of face bare Sardiocera. 36. Abdomen conical or elongate oval. ..... 37 Abdomen cylindrical or elongate-conical, much longer than thorax. 38 37. Middle legs of male disproportionately long (16, 17). Cholomyia. Middle legs but little if any longer than the others. Melaleuca. 38 Apical cell widely open; wings unicolorous (21). . Euantha. Apical cell narrowly open; wings nearly hyaline. . . 39 39. Eyes bare (6, 7) Leptoda. Eyes hairy Uramyia. 40. Abdomen cylindrical, long and attenuated at base. Cordyligaster Abdomen oval or conical, not petiolate. .... 41 41. Frontal bristles descending below base of antennae(5). Chsetona. Frontal bristles not descending below base of antennae. . 42 42. Third vein with a row of bristles. . • . . . 43 Third vein without bristles, save at base 45 43. Third antennal joint four times the length of the second. Thelairodes. Third joint about twice the length of the second. . . 44 DEXIID^. 3^y 44. With discal and marginal macrochaetae (20). . Thelaira. Without discal macrochsetse. .... Polygaster. 45. Abdomen yellow, with or without black markings. . . 46 Abdomen black, sometimes partly whitish or cinerous. . 47 46. Apical cell broadly open Xanthodexia. Apical cell narrowly open (8, 9). ... Calodexia. 47. Curvature of fourth vein arcuate. . . Rhombothyria. Curvature of fourth vein angular. ..... 48 48. Arista short-hairy. Pseudoraorinia. Arista distinctly plumose. . . . . . . . 49 49. Eyes bare (18) Morinia. Eyes hairy Oomyops. The following genera are not included in the foregoing table: Echi- nodexia, Eudexia, Paraprosena, Dexiosotna, Pseudodexia^ Cyrto- soma, Theresia, Homodexia. NOTES ON THE FIGURES. BY PROK. C. H. T. TOWNSEND. Figs. 3,4. I propose for this species the new genus Euchcetogyne. I identify the species with specimens from the Sierra Madre of western Chihuahua. 5. In the genotype the apical cell probably ends at the wing tip. 8, 9. The figures agree with a specimen of Calodexia in U. S. Nat. Mus. but the posterior cross-vein is nearer the bend of the fourth vein. 10, II. Both figures agree with specimens of Chnofieura, female, and the wing with Ptilodcxia also, but not the head. 12, 13. The figure of the head is typical of Myiocera, except that there is a pair of strong reclinate vertical bristles in female. 14, 15. Rhamphinina, sp. male. The figures agree with speci- mens which I refer to Rharnphinina, differentiated from Rhyncho- dexia by the absence of facial carina. 19. Rhynchodexia, sp. male. Appears to be this genus, distin- guished from EuchcEtogyne by the absence of strong reclinate vertical bristles. 20. Thelaira, sp. male: Quite typical, but the species is probably not T. longicornis, which Brauer refers to Pseudodexta. 21. Euaniha liturata male. A costal spine is present. The wing of the female is more deeply clouded. 22. Melanophora r oralis. The petiole of apical cell originates usually a little before point opposite to end of second vein. 33 LVIII. FAMII.Y TACHINID^. Fig. 147. Exorista ajfinis, enlarged. After Washburn. Rather small to rather large, bristly flies, thinly or not at all pilose, usually thick-set. Eyes pubescent or bare; those of the male more approximated than those of the female, or contiguous. Front with a row of bristles on each side, descending to or below the base of the anten- nae; with or without orbital bristles. First antennal joint short; second joint usually shorter than the third; third joint usually more or less elongated, sometimes dilated or fissured; decumbent; arista bare, three-jointed, the first joint always short, often atrophied and impercepti- ble; second joint sometimes elongate (13) and geniculate. Face alwxys with a well-marked median depression, which someVmes has a carina in its middle. Proboscis sometimes elo\ngate and slender, but usually short and with broad labella; palpi never with more than one joint, which is sometimes rudimentary. Ocelli present. Abdo- men composed of four or five visible segments; with mar- 358 TACHINID^. 32g ginal and lateral, and usually with discal bristles; some- times nearly covered with strong, erect spines. Legs usually rather stout, seldom moderately elongate; always with bristles. All the veins of the wings simple; basal cells large; three posterior cells present, the first of which is always narrowed or closed (save in those rare cases in which the distal section of fourth vein is obliterated); aux- iliary vein distinct in its whole course. Squamae large. No other group of flies has presented so many difficul- ties to the student of systematic dipterology as the pres- ent one. In its entirety, with few exceptions, it is easily differentiated. Flies that have the arista bare (or at the most, pubescent), the squamae well developed, and the first posterior cell narrowed or closed, may be unhesita- tingly referred to this family. But the family is not always easily distinguished from the Dexiidae. The presence, however, of aristal plumosity, with the other characters of the more typical tachinids, that is those of which the dorsum of the abdomen is distinctly bristly, will remove doubt of the correct location of any species pos- sessing such characters, even when the legs do not have the elongation characteristic of the more typical dexiids. Unfortunately the differentiation of the genera and species is vastly more difficult, and will require much patient study even yet before a satisfactory stability is reached. The student should not be discouraged if he is not always sure of his results, — the most of us are often in doubt about Tachinidse. About one hundred and eighty-five genera have already been accredited to North America. Some of these will doubtless be reduced to synonyms, but not many, since the characters used for generic lim- itation are often exceedingly slight, such as in many other families are considered of specific value only. So inconspicuous are the distinguishing characters in many species that only the experienced eye will detect them. 36o NORTH AMERICAN DIPTKRA. For further study of the family the reader is referred to the various works of Brauer and Bergenstam, v. d. Wulp, Townsendand Coquillett. The habits of the mature fly are similar for nearly all the members of the group. They will be found on veg- etation, on leaves or flowers, in such places as are fre- quented by the hosts which they parasitize. Not a few will be caught with the beating net. The larvae of the more typical Tachinidae are thicken- ed, cylindrical and flattened below, the segments indis- tinctly differentiated, with transverse and lateral swel- lings, bare or provided with fine, short shines. They are amphipneustic, the anterior spiracles small and point- like or multipartite, the posterior stigmatic plates large, strongly chitinized, and each with three, internally con- vergent grooves. The antennae are wart-like, with two, ocellus-like, chitinous rings, one lying below the other. There are but two mouth-hooklets, porrect and but little curved. The puparia are oval, with the segments slightly differentiated; the skin is finely wrinkled, and both ends are rounded. In Ocyptera and Gyrnnosoma^ and probably in allied forms, the larvae have a chitinous, anal stigmatic tube; and the puparia have six or two, similar processes. The larvae of Hyalomyia are translucent, smooth and meta- pneustic, the mouth-hooklets very large; there are two, short, divergent, anal tubes. The larvae of this group are all parasitic in habit so far as known, and the parasitism is probably confined to the early stages of other insects; and the individual fly is not very particular in the choice of larvae which she parasitizes. Their usefulness in keeping injurious in- sects in check is immeasurable. By far the largest number of species are parasitic upon Lepidoptera, of which not less than four hundred have TACHINID^. 361 been recorded. About seventy species are known to be parasitic upon Hymenoptera, less than forty upon Cole- optera, a score upon Orthoptera, five upon Hemiptera, and as many upon other Diptera. The figures of the first plate (1-17) were kindly made by Professor Aldrich. The remainder (18-114), by my- self, have been drawn as carefully as possible. Not being a specialist in this family, it was not always possi- ble to be quite certain of the characters. Professor Townsend has, however, with great kindness examined the figures carefully, and has criticised them in an ap- pendix to this family (p. 378), which should be consulted by the student. TABIvK OF GENERA. BY PROF. C. F. ADAMS. 1. Apical cell (first posterior) ending at or close to the extreme wing tip. 2 Apical cell ending some distance before the extreme tip. . 76 2. Abdomen without macrochsetse. ...... 3 Abdomen with macrochaetse. . . . . . . . ii 3. Sides of face bare. ......... 5 Sides of face with bristly hairs. ...... 4 4. Third and fourth veins nearly equally convergent. Gymnophania Fourth vein more convergent than the third (18, 19). Acaulona 5. Hind tibiae outwardly ciliated with a row of erect bristles. . 6 Hind tibiae not ciliated. ..... . ■ . 7 6. Apical cell open. ...... Homog'ema. Apical cell closed. ...... Trichopoda. 7. Abdomen subspherical, the upper side very convex. . . 8 Abdomen without such convexity. ..... 10 8. Antennae not reaching the lower third of the face. . . 9 Antennae reaching at least the lowest fifth of the face. Gyranosoma. 9. Abdomen with five visible segments (18, 19). Acaulona. Abdomen with only four visible segments, or the fifth very short (10) Cistogaster. 10. Sides of the front hairy except a narrow space along each eye (20) Alophora. Sides of front bare except two or three rows of hairs along each side of the frontal vitta (21). . . . Phorantha. 11. Sides efface with hairs or macrochaetae on lower half. . 12 Sides of face, or at least lower half, bare. .... 25 362 NORTH AMERICAN DIPTERA. f p 0 B L I C ) Fig. 148. Tacliinwlap. 1, Masia^rfi festi7ia}is, wing; 2, Aphria occidentalism wing: 3, ^pallanzania hebes, head; 4, Blepharipeza adnata, tibiae; 8, Acemyia dentata, antennae; 6, Atacta, sp. head; 7, Peleteria neglecta, liead; 8, Plagia americana, wing; 9, Tachina rohusta, head; 10, Cistohora mexicami, wing, head; .84, Crii])tomeigenia eumi/othi/roides. head; 35, M i/io/thas/a a^nea, head; 8(5, Am'sia, sp. head; 87, 38' Hemyda uuraUi, wing, head; 89, Elajihi palpus, sp. wing: 40, 41, Me1hrgs insolita, head; 90, Opsidia gonioides,]\eii'.V, 91, Hgstricia pollinosa, liead; 92fClgtio7ni/ia flava, head. 84 370 NORTH AMERICAN DIPTERA. 93 Fig. 152 TACHINID^. 3yi 70. Eyes descending below vibrissae Telothyria. Eyes not descending below vibrissae. . . •. Olytiomyia. 71. Palpi absent (70) Beskia. Palpi present. . . . . . . . . . 72 72. First vein partly bristly. 73 First vein bare . . .74 73. Two orbital bristles in the male; apical pair of scutellar bristles long Ging-lymyia. No orbital bristles in the male; apical pair of bristles short (32) . Epigrimyia. 74. Proboscis not geniculated near middle. .... 75 Proboscis geniculated near middle (78) . . . Siphona.* 75. Facial ridges bristly on at least the lower half. . Isoglossa. Facial ridges never bristly on more than the lowest fifth (82) . Epigrimyia. 0 76. Ivast section of fifth vein or its fold more than one-half as long as the preceding. ......... 77 Last section of fifth vein not more than one-third the length of the preceding. .......... 88 77. First vein wholly or partly bristly. ..... 78 First vein bare 81 78. Head at vibrissae as long as at base of antennae. . . 79 Head at vibrissae shorter than at root of antennae (8) . Plagia. 79. Fifth vein bristly Plagiomima. Fifth vein bare. ......... 80 80. Sides of face with strong bristles. . . . Goniochaeta. Sides of face with short, scattered hairs (79). Siphoplagia. 81. Sides of face on lower half bare -82 Sides of face with macrochaetae or bristly hairs on at least a por- tion of lower half. ........ 85 82. Facial ridges bristly on their lowest third only. ... 83 Facial ridges bristly at least to their upper third. . . 84 83. First posterior cell closed in the margin (62). Heteropterina. First posterior cell long petiolate (25). . . Euscopolia. * Bezzi would call this genus Bucentes I^at. ; see Muscidae. Fig. 152. Tachinidae. 93, Demoticus venatoris, liead; 94, Hyphantrophaga hyphantrice, head; 95, Jurinia hystricosa, wing; 96, Paradidyma, sp.; 97, 98, Plagiprospherysa parvipalpis, wing, head: 99, Micropthalma disjuncta, head; 100, Jurinella amhigua, head; 101, Nemorcea nigricornis, head; 102, Archytas apicifera, antenna; lOo, Dichocera lyrata, head; 104, Dichocera lyrata, anten- nae from in front; 105, Muscopteryx, sp. head; 106, Hllarella decens, head; 107, Neotractocera , sp., head; 108, Pseudotractocera neomexicana, head: 109, Frontina archippivora, head; 110; Senotainia ruhriventris, head; 111, Gcediop- sis mexicana, head; 112, Leskia analis, wing; 113, Bomhyliomyia ahrupta, head; 114, Chfeioglossa picticornt's, (the long, slender proboscis omitted) head. 372 NORTH AMKRICAN DIPTERA. 84. Cheeks about one-fourth or less of eye-height (97, 98) . Plagiprospherysa. Cheeks nearly as broad as eye-height. . . Baumhaueria. 85. Byes bare, or with indistinct hairs. ..... 86 Byes distinctly hairy CyrtophlcBba. 86. Sides of face without stout macrochaetse. .... 87 Sides of face with one or more pairs of macrochaetae. Paraplagia. 87. Arista thickened almost to its tip; third vein bristly nearly to an- terior cross-vein. ...... Metaplagia. Arista not thickened to the middle; third vein bristly less than half way to the cross-vein (62). . . Heteropterina. 88. Sides of face bare on lower half. ...... 89 Sides of face with hairs. . ... . . . 140 89. Vibrissse distinctly above oral margin. .... 91 Vibrissse on a level with oral margin 115 Vibrissse very vestigial. ....... 90 90. Wings nearly wholly brownish black; black species (58, 59) . Penthosia. Wings brownish anteriorly only. . . . Olinogaster. 91. Eyes bare. .......... 92 Eyes hairy. .......... 109 92. Penultimate joint of arista more than twice as long as broad. 93 Penultimate shorter or only slightly longer than broad. . 94 93. Proboscis beyond basal articulation at most one and two-fifths times the height of head (2) Aphria. Proboscis beyond basal articulation at least two and one-third times the height of head (114) . . . Cheetoglossa. 94. Palpi absent or vestigial (54) Ocyptera. Palpi present. ......... 95 95. Proboscis beyond basal articulation at least one and one-third times the height of head (2) Aphria. Proboscis beyond basal articulation at most one and one-fifth times the height of head. ........ 96 96. Antennae reaching at least the lowest fourth of face. . . 105 Antennae not reaching below the lowest third. . . . 97 97. Vibrissse at less than half the length of the second antennal joint above the oral margin. ....... 98 Vibrissse at least the length of the second joint above the oral margin. .......... 99 98. L/Owest frontal bristles not below the base of the second antennal joint (72, 75) Pachyophthalmus. Lowest frontals below the middle of second antennal joint (6) . Atacta. 99. Lowest frontals below middle of second antennal joint. . 100 Lowest frontals not below middle of second joint. . . 103 100 Ocellar bristles directed forward. ...... loi Ocellar bristles wanting. ..... Belvosia. TACHINID^. 373 loi. Hind tibiae not with distinct cilia externally. . . . 102 Hind tibiae ciliated externally; apical cell open (6). Atacta. 102. Apical cell open. Biomyia. Apical cell closed (108). . . • Pseudotractocera. 103. Cheeks less than one-third as broad as eye-height; arista thick- ened almost to tip (89) . ... Melanophrys. 104. Frontal bristles in two rows (110). . . . Senotainia. Frontal bristles in four rows (72, 75) . Pachyophthalmus. 105. Vibrissae at most only one-half the length of second antennal joint above oral margin . 108 Vibrissae at least the length of second antennal joint above oral margin. .......... 106 106. Ocellar bristles directed forward 107 Ocellar bristles wanting Belvosia. 107. Hind tibiae externally ciliated (6) Atacta. Hind tibiae not ciliated Biomyia. 108. Ivower frontal bristles below base of second antennal joint. Siphosturmia. Lowest frontals not below base of second joint (89) . Melanophrys. 109. Palpi absent or vestigial (77) Linnsemyia. Palpi present. ......... no no. Sides of face at narrowest part less than one-third the width of the median depression. . , . . . . . 114 Sides of face half as wide as the median depression, or more, in 111. Dorsum of abdomen without macrochaetae. Mystacomyia. Dorsum of abdomen with macrochaetae 112 112. Face in profile convex Macromeigenia. Face in profile perpendicular . 113 113. Abdomen with marginal macrochaetae only. . Bolomyia. Abdomen with discal and marginal macrochaetae. Paramesochseta. 114. Bend of fourth vein with a long appendage; second and third seg- ment of abdomen usually without discal macrochaetae (lOl) . Neraorgea; Bend of fourth vein at most with an extremely short appendage. second and third segments of abdomen with discal macrochaetae. Panzeria. 115. Kyes hairy. 116 Eyes bare. .......... 121 116. First vein with two or more bristles on outer half. Exoristoides. First vein bare. ......... 117 117. Abdomen bright or bluish green; facial ridges never bristly on more than the lowest fourth (56) . . . Gymnochaeta. Abdomen black or more or less yellow. . . . . 118 118. Facial ridges not bristly on more than the lower half . . 119 Facial ridges bristly on at least the lower two-thirds. . 120 374 NORTH AMERICAN DIPTERA. 119. Sides of face at narrowest part less than one-third the width of the median depression (fig. 147). . . . Exorista. Sides of face more than one-half the width of the median depres- sion . . . Metaphyto. 120. Bend of fourth vein with a long appendage or distinct fold. Euphorocera. Bend of fourth vein without such fold or appendage. Phorocera. 121. First vein bristly except at tip and base. . . . Houghia. First vein bare. ......... 122 122. Facial ridges not bristly on more than lower half. . . 123 Facial ridges bristly on the lower two-thirds. Pseudochseta. 123. Antennae reaching at least the lowest fourth of face. . 126 Antennse not reaching below lowest third. . . . 124 124. Vibrissae less than one-half the length of the second antennal joint above oral margin 125 Vibrissae at least the length of the second antennal joint above oral margin (5) Acemyia. 125. Third vein with a single bristle at its origin. . Comatacta. Third vein bristly more than one-half the distance to anterior cross-vein Paraphyto. 126. Lowest frontals below base of second antennal joint. . 129 Lowest frontal not below base of second antennal joint. . 127 127. Facial depression without median carina. . . . 128 Facial depression with a carina; apical cell closed, the petiole twice the length of anterior cross-vein (80, 81) . Euthera. 128. Lower anterior corner of third antennal joint produced tooth- like (5) Acemyia. Antennae not so produced (44, 53) . . Vanderwulpia. 129. Second abdominal segment without more than four marginal macrochaetse; or, if with more; the hind tibiae not ciliate. 130 Second abdominal segment with at least six marginal macrochae- tae (4) Blepharipeza. 130. Hind tibiae ciliated externally. ..... 131 Hind tibiae not ciliated externally. ..... 135 131. Facial ridges bristly almost to the middle. . . . 133 Facial ridges bristly on less than the lowest fourth. . 132 132. Bristles of cheeks covering at least the lower two-thirds. Sturmia Bristles of cheeks covering less than the lower half (94) . Hyphantrophaga. 133. Frontals with at least three backwardly directed bristles in each row; abdomen largely or wholly opaque pollinose. . 134 With only two such bristles in each row; abdomen shining. Parachseta. 134. With two or three backwardly curved bristles outside of the frontal rows Pseudochseta. Front without such macrochaetae (109) . . . Frontina . 135. Bend of fourth vein without appendage. .... 137 Bend of fourth vein with appendage or distinct fold. . 136 7lc:ar1kckiS£££t TACHINID^. 275 136. Arista distinctly pubescent; facial ridges bristly on the lower five-sixths. Prospherysa. Arista bare; facial ridges at most bristly on lower three-fifths (9) , * Tachina. 137. Diameter of head at vibrissse as great as at root of antennae. 138 Head much shorter at vibrissae than at base of antennae. 139 138. Facial ridges bristly on at least the lower two-thirds. Tachinopsis. Facial ridges bristly on less than the lowest third (93) . Demoticus. 139. IvOwer front corner of third antennal joint produced tooth-like (5). Acemyia. Lower front corner not so produced (1) . . . Masicera. 140. Vibrissse on a level with oral margin. .... 141 Vibrissae disiinctly above the oral margin. . . . 161 141. First vein wholly or partly bristly. ..... 142 First vein bare. ......... 143 142. Apical cell open (83). Chaetoplag-ia. Apical cell closed and long petiolate (40, 41) . Metachceta. 143. Byes distinctly hairy. ....... 144 Kyes bare, or with short, indistinct hairs. . . . 146 144. Sides of face without macrochaetae. . . . "Winthemia. Sides of face with macrochaetae, at least near lower end of eye. 145 145. Third joint of antennae at least five times the length of the second. Paradidyma. Third joint scarcely as long as the second (105) . Muscopteryx. 146. Apical cell closed. . . . . . . . . 147 Apical cell open; if closed, the petiole less than one-fifth the length of the hind cross- vein. . . , . . 149 147. Frontals not, or scarcely descending below base of antennae. 148 Frontal descending considerably below base of antennae. Phorichaeta. 148. Proboscis two and one-half times the height of the head. Trochilodes. Proboscis short, not longer than height of head, Miltogramma. 149. Facial ridges bristly on at least the lower half. . Araba. Facial ridges bristly on less than lower half. . . . 150 150. Antennae reaching only slightly below middle of face. . 151 Antennae reaching to or below lowest fourth. . . . 153 151. Apical cell open. ........ 152 Apical cell closed, the petiole as long as the anterior cross-vein. Euthypr osopa . 152. Hind tibiae fringed externally with bristles of equal length. Thysanomyia. Bristles of hind tibae of unequal length. . Brachycoma. 153. Face with macrochaetae, at least near lower end of eye. . 154 Sides of face without macrochaetae. ..... 160 376 NORTH AMERICAN DIPTERA. 154. Head at vibrissse as long as at base of antennee. . . 155 Head at vibrissae much shorter than at base of antennae. 157 155. Posterior cross-vein much nearer to bend of fourth vein than to the anterior cross-vein. . . . . . . 156 Posterior cross-vein at most only slightly nearer to bend of fourth vein than to anterior cross-vein. . . . Trichogena. 156. Fifth vein not reaching the hind margin (39, 61) . Elachipalpus. Fifth vein reaching the hind margin. . Brachycoma. 157. Facial ridges almost parallel; sides of face at narrowest part nearly as wide as the median depression. . . . 158 Facial ridges widely diverging below; sides of face less than one- half as wide as median depression. . . . . 159 158. Fifth vein not reaching the wing margin (39, 61) . Elachipalpus. Fifth vein reaching the wing margin (90) . . Opsidia. 159. Fifth vein not reaching the wing margin (39, 61) . ElachipaljDUS. Fifth vein reaching the wing margin (88). . Metopia. 160. Head at vibrissse much shorter than at root of antennae. Hilar ella. Head at vibrissae as long as at root of antennae. Brachycoma. 161. Head at vibrissae much shorter than at root of antennae. 162 Head at vibrissae as long or longer than at root of antennae. 168 192. Kyes distinctly hairy. 163 Eyes bare or with very short hairs. . . .. . . 164 163. Facial ridges not bristly on more than lowest fifth; antennae of male divided longitudinally (103, 104) . Dichocera. Facial ridges bristly on at least the lower half (111) . Graediopsis. 164. Ocellar bristles wanting (99) . . . . Microphthalmia. Ocellar bristles present. . . . . . . . 169 165. Ocellar bristles directed backward, robust. . . . 166 Ocellar bristles directed forward. . . . . . 167 166. Front opaque, the vitta deep brown or black (3) . Spallanzania. Front shining, the vitta light yellow (12, 13). . Gonla. 167. Frontal ridges bristly on less than the lowest fourth (99). Microphthalmia . Frontal ridges bristly on at least the lower half (87) . Chsetogsedia. 168. Palpi absent or vestigial. ....... 169 Palpi well developed. . . , . • . . 175 169. With one or more stout macrochaetae on either side near lower end of eye. ......... 172 Without such macrochaetae. . . . . . . 170 170. Abdomen with discal macrochaetae. . . . . . 171 Abdomen without discal macrochaetae. . . Gymnomma. 171. One discal and one marginal pair of macrochaetae on second ab- dominal segment. ..... Parepalpus. TACHINID^. 3yy With more than one discal and marginal pairs of macrochaetse on second abdominal segment. .... Epalpus. 172. Sides of face with one macroch setae; slender (39, 61). Tricophora. Sides of face with two or three macrochaetse. , Cupliocera. 173. Face on lower half of its sides bare (113). Bombyliomyia. At least a portion of sides of face with hairs or macrochaetae. 174 174. Kyes distinctly hairy. . . . . . . . 175 Byes bare or with very short hairs. ..... 176 175. Third antennal joint almost straight on front edge, the tip sub- truncate (113) Bombyliomyia. Third antennal joint strongly convex on front edge, the tip rounded (103) Jurinella. 176. Ocellar bristles absent. . . . . . . . 171 Ocellar bristles present. . . . . . . . 181 177. Sides of face without macrochaetae. . . . . . 178 Sides of face with two or three macrochaetae (7) . Pelateria. 178. Second segment of abdomen never with more than eight mar- ginal macrochaetae (11, 102) .... Archytas. Second segment with at least twelve marginals. . . 179 179. Palpi gradually thickened from base; proboscis shorter than height of head. ........ 180 Palpi thickened on distal three-fourth; proboscis at least one and one-third times the height of head (17) . . . Dejeania. 180. Abdomen subquadrate, the tip deeply emarginate (fig. 21, p. 44). Paradejeania. Abdomen conical, the tip not emarginate (95). . Jurinia. 181. Vibrissje at least the length of the second antennal joint above oral margin (46) .... Eucnephalia, Amobia. Vibrissae at most only half the length of the second antennal joint above the oral margin. ..... 182 182. First posterior cell closed. .... Trochilodes. First posterior cell open. . . . . . Echinomyia. Owing to doubt of their true position, the following genera have not been included in the above table. The references to them will be found in Aldrich's catalogue: Eliozeta, Hiniantostoma ^ Heniithrixion, Meriana, Parahypochccta^ Metadoria, Evibrissa, Besseria, Peteina, Masistyliun, Steiietiia, Mys- tacella, Chcstogena, Hypertrophocera , Tricolyga^ Teiragrapha, Dcec- chcsta^ Neotractocera (107), Paragcedia^ Cestonia, Gadiophana^ Cryplopalpus, Hystricia. JMicrocIiira, Tropidopsis. 378 NORTH AMERICAN DIPTERA. NOTES. BY PROF. C. H. T. TOWNSEND. These notes are given in advance of a forthcoming paper, which will give characterization of new, and reasons for maintaining certain old genera and species mentioned herein, besides pointing out distinctions between various forms. When characters are given for species, unless otherwise stated, it is to be understood that the same have been drawn from specimens in the United States National Museum, after compar- ison with the figures. Fig. I. The American species is probably not festinans. Fig. 2. The figures agree perfectly with type and cotype in the National Museum. Fig. 3. Cnephalia pansa. The figure is apparently made from a male specimen, but does not show the characters clearly. The third antennal joint is too long, the second too short. After a careful com- parison of European and American specimens, I am convinced that Spallazania hebes does not occur in America. Fig: 4. Rileyfnyia adusta. The genus should be maintained. Fig. 5. The type, a female, has the third antennal joint just twice as long as the second. The eyes descend almost as low as the vibrissse. Fig. 6. Atacta, sp. Not typical of Atacta, which has cheeks wider, appearing one-fifth of eye-height from side view; second antennal joint strongly elongate; antennpe inserted rather below middle of eyes. Fig, 8. Plagia aurifrons. This appears to be the wing of P. auri- frons, which is distinct from americana. Fig. 9. Tachinomyia robtista female. The figure does not show vibrissal insertion high enough, nor the cheeks wide enough. Fig. 10. Gymnoclytia im^naculata. This species is not congen- eric with the European Cistog aster globosa. Fig. II. Archytas lateralis. Ptilinal suture apparently omitted; a bristle from opposite side of front included. Fig. 12, 13. Goniafrontosa. Not G. capitata, which has second aristal joint about as long as the third. Although the lengths of the ari.stal joints are variable in Gonia, they do not vary so much as to in- validate their usefulness. Fig. 14. Clausicella &p. Not typical of Thryptocera. The epistonia is not so prominent in Thryptocera, the frontal bristles are stronger, aristal joint is proportionally longer. Fig. 16. Argyromima setigera. Not typical of clausicella, which has apical cell closed. Fig. j8, 19. Acaulona cristata. The apical cell is sometimes short petiolate. Fig. 20. Alophora fumosa. Agrees with type. Not very typical of Alophora, but best referred here provisionally. Fig. 21. Hyalomyia, sp. Typical wing, not Phorantha. TACHINID^. 379 Fig. 22. Alophora, sp., wot Phorantha. Fig. 25. Euscopolia dakotensis. Third vein is bristly more than half way to cross-vein. Figs. 30, 31. Neophyto setosa. Is not a Phyto. I propose to call the genus Neophyto, and will give full details elsewhere. Figs. 32, 33. Rhinophora inexicana. Small cross-vein lacking. The fourth vein of Rhinophora is normally not represented by a stump beyond apical cross-vein, but by a wrinkle. Fig. 34. Euphantopteryx eurnyothyroides; is not E. theutisWsil^. Fig. 35. Phasioclista, sp. female. Fig. 36. Anisia sp. This genus, to b*_ employed at all, will have to be restricted to species of some particular type. The genus as orig- inally established includes many diverse forms. Figs. 39, 61. Copecrypta rtijicanda, new genus. Figs. 40, 41. Metachcsta atra. Apparently this species, though the type in the National Museum has the apical cross-vein only very slightly, almost imperceptibly bisinuate. Figs. 42, 43, 45 and 52. Diaphoropeza hraiieri, new genus. Figs. 44, 53. Oediniapeza iownsendt. This and the preceding spe- cies are not congeneric, and neither one can be referred to Vander- zuulpia or Atrophopoda. I propose the former name for braiieri and the latter for townsendi, and they will be described elsewhere. Fig. 46. Eucnephalia gomoides. The arista is shorter than the third antennal joint; there are weak bristles on the wide parafacials, and the facialia are bristly more than half way up* Fig. 50. Not a true Phorocera, nor can it be referred to Plagipros- pherysa or Prosopodes. Fig. 51. Didyma calyptrata. Not a true Didynia, for which D. albo^nbicans Wulp should be taken as the type. Fig. 55. Sciasma nebttlosa. Small cross-vein about midway between hind cross-vein and end of first vein. Fig. 56. Frontal bristlas usually descend to insertion of arista. Fig. 57- Parexorista nobilis. Figs. 63 and 64. Paranophora diademoides. This is not Ervia triquetraoi Olivier, nor of Robineau Desvoidy, nor does it belong to Ervia Desv. It is, however, the species so determined by Coquillett. The frontal bristles descend one bristle lower. Figs. 65. 66. Aporia limacodis. This is a true Aporia, not a Mac- quartia. The head is that of a female. Dexia tristis Walk, seems to be an Aporia, bvit quite impossible to identify from the description. Figs. 67, 68. The figures agree with a male cotype of Leiicostoma nigricornis, except that the third antennal joint should be the same length as the second. I consider nigricornis and senilis distinct and will give reasons elsewhere. Figs. 69, 79. Siphoplagia anoniala. First vein bristly to opposite end of auxiliary, and third vein to opposite origin of apical cross-vein. 38o NORTH AMERICAN DIPTKRA. Figs. 71 and 76. Xanthomelanodes arcuata. Figure evidently made from an oblique viewpoint. Xanthonielana is preoccupied in Aves (Bonaparte, 1850). Figs. 72, 75. Sarcomacronychia, sp. Not Pachyophthalnius. I five elsewhere distinctive differences. Figs. 73, 74. Goniochcsta plagiodes. A small costal spine some- times. The frontal and parafacial bristles usually appear as a con- tinuous row, the latter directed downward. The foremost frontali inserted opposite base of third joint. There are three procHnate orbi- tal bristles in each sex, the middle ones sometimes weak. Fig. 78. Siphona illinoisensis. Differs from geniculata in the widened and flattened third antennal joint, convexity of third aristal joint, etc. Figs. 80, 81. Euthera tentatrix'. The second antennal joint is sometimes almost as long as the third, the latter in such case being shortened so as to make the antennae scarcely longer than face. The third joint is normally of equal width throughout; truncate at tip. Fig. 82. Drepanoglossa lucens. The anterior upper fronto-orbital (re- clinate) bristle is stronger than any other save the vertical. I give elsewhere the differences between Epigrhnyia and Drepanoglossa. Figs. 84, 85. Euthyprosopa petiolata. Compared with cotype the front pair of ocellar bristles is longer than shown in figure, and third antennal joint is pointed at apex. The frontal bristles are sliorter. The hind cross-vein may be nearer the angle of the fourth vein in some specimens than in others. Fig. 87. Chcstogcedia acroglossoides. Apparently the male of Fron- tina acroglossoides Towns. I give elsewhere distinctions between this species and Baiinihaueria analis Wulp, with notes on ChcFtogcsdia, and an allied new genus. The figure should show the outer row of frontal bristles differentiated from the bristly hairs of parafrontals and the second antennal joint longer to agree with eastern specimens which I am inclined to identify as this species. Fig. 89. Atropharista jurinoides. I give reasons elsewhere for maintaining this genus. Fig. 91. Eujurinia pollinosa. I propose this name for //v^/r?V?a polluiosa Wulp. A specimen from Mexico differs from the figure in the somewhat wider cheeks and the not bowed palpi. Fig. 92. Euclytia flava. I propose the new geniis Euclylia for Cly- tia flava and give particulars elsewhere. Fig. 93. Neofischeria flava Towns, n. g. et n. sp. The genus and species are characterized elsewhere. This is not Demoticus venatoris Coq. , which by the way is not a Demoticus, and for which I propose the new genus Parafischeria. The figure should show the well de- veloped palpi, which are elongate, a httle thickened distally and slightly curved. Fig. 94. Hyphanirophaga hyphantricE, male. The parafacials be- low and the cheeks should be narrower to agree with topotypes in the National Museum. TACHINID^. 381 Figs. 97, 98. Plagiprospherysa valida. The parafacials are not so wide below in tototypes in the National Museum. The species is apparently closely allied to P. parvipalpis, but needs comparison. Fig. 100. Pseudohystricia ambigua, male. The genus differs from Jurinella in the wider parafacials and more produced front. Fig. loi. Saundersia sp? Can not be a Neniorcea, which has the epistoma less prominent and the face more receding and lengthened. Fig. 105. Muscopteryx sp. Probably M. chcEtosiila. Fig. 106. Compared with a cotype there is a pair of short reclinate fronto-orbital bristles opposite the ocellar pair, wanting in figure. Fig. 109. Achcstoneura archippivora, maXo.. This is Achcstoneura and not Frontina. Notes on the distinction will be published else- where. Fig. no. Senotainia flavicornis. t\i\sisdi\s\\wQ.\.iro-a\.rubriventris. Fig. III. Gcsdiopsis s-^'i This maybe tnexicana, but is not the species so determined by Coquillett, which I shall describe as a new genus and species, Poliophrys sierricola. Fig. 112. Stofnatodexia analis. If Dexia analis Say is congeneric with Dexia diadetna Wied. and the species figured is correctly iden- tified with the former, it is incorrect in having the first posterior cell end so far from the wing tip. Fig. 113. Bombyliomyia abrupta. The arista is longer than the third antennal joint. Fig. 1 14. Chcetoglossa picticornis. The figure lacks the long and extremely delicate proboscis. National Museum, June, 1907. 35 LIX. Family HIPPOBOSCID^. Fig- 159- Pseudolfersia fumipennis, enlarged. After Lugger. Head flattened, usually attached to an emargination of the thorax; face short; palpi forming a sheath for the proboscis, not projecting in front of the head; anten- nae inserted in pits or depressions near the border of the mouth, apparently one-jointed, with or without a ter- minal bristle or long hairs. Eyes round or oval, ocelli present or absent. Thorax flattened, leath- ery in appearance; scutellum broad and short. Halteres small or rudimentary. Abdomen sac-like, leather}^ in appearance, the sutures indistinct. Legs short and strong, broadly separated by the sternum; tarsi short; claws strong and often denticulated. Wings present or absent; the veins always approximated to the anterior border, with less strong ones running obliquely across the wing. The flies of this family are always parasitic in the adult condition upon birds and mammals ; they have a pecu- 382 HIPPOBOSCID^. 383 liar louse-like appearance, and one often encounters them in handling recently killed birds, especially the raptorial birds. They have a quick, short flight, seek- ing the beard or hair of the collector within which they run nimbly, seeking to hide. The following table is based chiefly upon Speiser's studies of the genera of the world. Fig. 160. Hippoboscidse, Streblidfe. i, tridentate claw; 2, Ornith- omyia, wing; 3, Aspidoptera, wing (Speiser) ; 4, Trichobius, w^'m^ (Speiser, the slight emargi n ation of ihe distal wing border is not shown); 5, Strebla, wing (from specimen from southern Kansas, E. A. Popenoe). TABLE OF GENERA. 1. Wings functional. ......... 2 Wings vestigial or wanting. ....... 8 2. Claws simple, that is with no accessory tooth between the enlarged basal plate and the tip. ....... 3 Claws with an accessory tooth. ...... 4 Three longitudinal veins present; wings caducous, often broken and ragged, especially in the female. . . . Lipoptena. Six longitudinal veins; wings not caducous. . . Ornithoica. Anal cross-vein present, the anal cell complete. ... 5 Anal cell open, not closed by a cross-vein. .... 6 Ocelli present (2). Ornithomyia, Ornithopertha, Ornithoctena. Ocelli absent. ....... Stilbometopa. Wings lanceolate, the tip rounded; scutellum truncate. Lynchia. Wings of usual shape; scutellum not truncate. ... 7 Distance of oral border from frontal suture as great as from suture to vertex (fig. 159) Pseudolfersia. Distance from oral border to suture distinctly less than from sut- ure to vertex . . Olfersia. Wings vestigial; halteres present. ...... 9 Wings and halteres wholly wanting. . . Melophagus. Claws simple Lipoptena. Claws with an accessory tooth. . . Brachypteromyia. 3 4. LX. FAMII.Y STREBLID^. Head of moderate size, with a freely movable neck. Byes, when present, small, unfacetted, or with very few facets. Ocelli wanting. Antennae inserted in a pit, two- jointed, the second joint with a bristle. Proboscis short, not protrusible, thickened at base. Palpi broader than long, not forming a sheath for the proboscis, projecting, leaf like in front of the head. Abdomen with a distinct basal segment, the other segments rarely distinguishable, the first segment with peculiar bristles for the protection of the wings when at rest. Hind coxae always enlarged; fifth joint of tarsi usually enlarged and elongate. Claws never distinctly toothed; pulvilli present. Wings some- times wanting or vestigial; when present the surface pubescent and the veins rather stout. Fig. i6i. Megistopoda {Pier ellipsis) aranecc, enlarged (Speiser). The members of this small family of cosmopolitan dip- tera, are, with the exception of one reported case, exclu- 3^4 STRKBIvID^. 385 sively parasitic upon bats. Their breeding habits are not well known. Kolenati believed them to be oviparous, but Speiser is of the opinion that their breeding habits are not unlike those of the Hippoboscidse. TABIvB OF GKNERA. 1. Wings functional, with six longitudinal and nearly parallel veins and three outer cross-veins. ...... 2 Wings vestigial or wanting, not functional 3 2. Thorax distinctly longer than broad; abdomen distinctly segment- ated, with two large proximal and three small distal segments; last tarsal joint not remarkably thickened (5) . Strebla. Thorax rounded, but little or not at all longer than broad; abdomen usually indistinctly segmentated; last tarsal joint thickened and elongate (4). Trichobius. 3. Legs of usual length (3) . .... Aspidoptera. Hind legs greatly elongated, twice the length of the body {Pter el- lipsis) (fig. 161). Meg-istopoda. LXI. Family NYCTERIBIID^. Small, spider-like, wingless flies. Head oval, folding back when at rest in a groove on the dorsum of the tho- rax. Antennae short, two-jointed, the oval terminal joint with bristles inserted in tubercles. Eyes and ocelli vestigial. Thorax depressed, laterally anteriorly with comb-like bristles. Abdomen oval, with more or less distinct segmental scutes. Legs long, the knees at rest prominent above the thorax. Femora broad; tibiae club- bed or shovel-shaped; metatarsus very long. Halteres pedunculate or sessile, in the latter case often indistinct. This family includes a considerable number of species, distributed widely in different parts of the world, all of them parasitic upon bats. Various attempts have been made to divide the group into smaller genera, but not with much success, Nycteribia being the only well defined genus known. Penicillidia differs in the more aborted and sessile halteres, and the species are of larger size, but I doubt its validity. 386 APPENDIX. During the printing of this work several genera new to America have been added in recent publications; other changes or additions I have ascertained by the examina- tion of types. The student is requested to insert marginal references in the body of the work wherever such changes or additions should be made. Page 25, near middle, for 'maxillae' read mandibles; fourth line from bottom for 'not' read seldom. Page 28, third line, strike out remainder of sentence beginning 'and it has been said', and see footnote, page 81. Page 35, Mr. Austen urges the abandonment of the term 'metatarsus', and I quite agree with him that the word, as used, is etymologically incorrect. Whether or not distinctive terms for the different tarsal joints are desirable I do not know, but I suggest the following: pro- tarsus, epitarsus, ynesotarsus, metatarsus, onychotarsus. Page 41, second line from bottom, for 'Cubital i, 2' read Medial i, 2, 3; next line for 'V3, Cubital 3' read VII i, 2, Cubital i, 2. Page 42, fig. 16, read Thereva, Therevidae. Page 86, last couplet, change to read: Antennae 14-jointed; 15 in Elephantoniyia. Antennae i6-jointed; 12 in Toxorhina. Page 91, read Tanypremna and Longurio. Pages 112, 114, first and seventh lines, for 'Ablabesiniyia\ read Tany- pus; fifth and fourth lines for 'Tanypus^ read Protenthes. Page 114, eighth line, for 'Isoplates\ preoc. read Tanypus. These corrections are by Prof. Johannsen. Page 140, near middle, for 'three' read two. Page 142, change last two lines to read: Palpi four or five jointed; antennae eight to twelve jointed, etc. Page 148, last line, for 'facts' read facets. Page 155, fifth line, insert twelve to before 'sixteen'. Page 162, Misgomyia Coq. (Proc. Ent. Soc. Wash. 1908, 145). Near Arthroceras, four posterior cells; two spurs on hind tibiae. M. obscu- ra Coq.-Va. Page 163. An examination of the type of Spania edeta in the Brit- ish Museum discloses the fact that it is a true Ptiolina; Spania is not known to occur in North America. Footnote on same page, for ^Rupellia' read Ruppelia. 3H7 388 NORTH AMERICAN DIPTKRA. Page 167, second line, insert flagellum of before 'antenna'. Page 168, Mr. Verrall informs me that the real difference between Neoexaireta and Actina is the ocular pubescence of the latter. He also adopts the name Chorisops Rond. in lieu of Neoexaireta. Page 181, for 'Alisonia' read Akronia, and for 'Acanthina' pre- oc. read Acanthinomyia Hunter. Myiochrysa coerulia is a syno- nym of Sargus viridis, according to Verrall. Page 180, near bottom, for 'Hamatopota' read Haematopota. Page 185. An examination of the type of Nothra americana Big. in Mr. Verrall's cabinet discloses the fact that the species is rightly placed. The venation is quite like that of Pterodontia^ save that there is only a slight angulation in place of the costal spur. This character, however, is not generic; it is disregarded in Opsebius. Mr. Verrall separates the genera by the presence of but a single aristal hair in Nothra, three in Pterodontia, but considering the differences used in generic separation in this family I think Nothra should be suppressed, Same page, for 'Appeleid' read Apelleia. Page 191, couplet 3, last line, insert often after 'proboscis.' Page 197, et seq. Asilidae. The distinction between the Leptogas- trinse and Dasypogoninse is apparently bridged over by a new genus from Brazil, represented by a specimen in my cabinet, of which a fig- ure is here given. The form is quite intermediate between Leptog as- ter and Plesiomnia. I am unable to make out the structure of the palpi. Fig. 163. New genus of Asilidae between Leptog aster and Plesiom ma. APPENDIX. 389 Dr. Back, who has examined the type of Sphageiis^ distinguishes the genus as follows: "Front and middle femora with a patch of short, stout bristles below; third antennal joint without excision on inner distal part. Sphageus. Front and middle femora without such patches of bristles; third an- tennal joint with excision on inner distal part; near the prox- imal margin of second and third abdominal segments with a white or yellowish pollinose crossband. . . Dizonias." Dr. Back also has made 'Habropogon' bilineatiis the type of a new genus, with the following definition: "Front not unusually widened above; bristles on the lateral margin and posterior callosities and scutellar margin numerous and well developed; third antennal joint short and broad; species much resembling Stenopogon in general appearance. Willistonina." Page 195, near middle for '■fraudigerd' read sabulonuni. Page 198, couplet 7, third line, for '7' read 8; in couplets 11 and 12, transpose '12' and '13'. Page 221; couplet 28 first line, for 'male' read female. Page 203. The genus Dasyllis, according to Col. Yerbury, comprises but a single species, the type; the American species should be united with Laphria. In this opinion I agree. According to the same author- ity Niisa is not a synonym for A^tdrenosoma^ which should be sub- stituted for that word in the eleventh line. Page 206. Mr. Verrall has resuscitated Dialineura Rond. for those species of Thereva having a hairy front, the face bare and the first antennal joint thickened. This definition will apply to some, prob- ably to all of those species included under 'Thereva, pt.' in couplet 3 and should be substituted therefor. Page 217. The type specimen of Rhabdopselaphus nius Bigot, one of the three or four genera of this family I had never seen, in Mr. Verrall's collection, lacks the head; otherwise it is a true Geron. Bigot erred in ascribing three submarginal cells to the genus. P. 256, couplet 53, for 'Licastrirhyncha' read Lycastrirhyncha Page 269, sixth line from bottom, for 'irridescent wing' read irides- cent wings. Page 277, couplet 3, first line, for '5' read 4; Oallopistromyia Hendel (1907) replaces Oallopistria, preoc. Eurycephalomyia Hendel (ibid) replaces Eurycephala, preoc. Page 279, first line, for 'Richarulia' read Richardia; Macroste- nomyia Hendel (1907) replaces Stenoraacra, preoc. Page 283, first couplet, for 'slump' read stump, and 'Toxytrypana' read Toxotrypana. Page 288. Hendel (Wien. ent. Zeit., 1907, 228) adopts Chcstocoelia G. T. for several species of Sapromyza, of which .S". angustipe^inis (5) is one, having long, pictured wings and small tubercles at the insertion of the fronto-orbital bristles. Camptoprosopella melanoptera, gen. et sp. nov. (Puebla, Mex.) he distinguishes from Physogenua by the nongibbous face, which is straight and retreating save at oral margin, 390 NORTH AMERICAN DIPTKRA. bare arista, etc. Siphonophysa he proposes for a new species [pectinata, Brazil) and probably S. sordida Wied. (Brazil and West Indies) hav- ing the arista plumose above only and a 'hinten ausgeschweiften Au- genrand'). ChcstoccEha maybe accepted, but the other two genera I think should be held in abeyance for the present. If they are accepted a dozen or more of the American species of Saproniyza and Pachyce- rina should receive new names. Mr. Hendel republishes the earliest paper of Meigen, of which two copies only are known to be in existence, in which scores of names, many of them repudiated later by Meigen, antedate some of the most common genera in diptera, and advises their substitution! He would have deserved the thanks of a long suffering public had he withheld these copies instead of republishing. Page 294, couplet 3, third line add: or the proboscis not long and geniculate. Phyllornyza nitefis I/oew is a Par amy ia. Page 295. Mr. Becker, recently, makes Ophthabnoinyia a synonym of Milichiella G. T. (1895); he is conect. Page 298. Geomyzidse. Pseudiastata Coq. (Proc. Ent. Soc. Wash. 1908), near Diastata, but second basal cell coalescent with discal; three fronto-orbitals; vibrissse present. — 7iebulosa Coq. Md. Muti- loptera Coq. (ibid.); wings six times longer than wide; arista short plumose; one fronto-orbital; no postverticals; vibrissae present; hind border of wing concave, — apicalis Coq. N. Dak. Page 299, second line from bottom, for 'posterior' read basal. Page 301, couplet 2, dele 'p. 80,12 and'. Page 303, eighteenth line, for 'and small' read or absent. Page 308, couplet 22, for 'sixth' read fifth. Page 325, Helomyzidae. A very useful review of the North American Helomyzidse, recently published by Aldrich and Darlington (Trans: Amer. Ent. Soc. xxiv, March, 1908) adds two new genera to our fauna. These, together with one recently described by Coquillett (Can. En- tom. March, 1907) may be differentiated from those given in the table as follows: Near Helomyza. a propleural, twodorsocentral, two fronto-orbitals, one sternopleural bristles present {pilosus, Mass.) Achsetomus Coq. Humeral, propleural, one dorsocentral, one fronto-orbital, no sterno- pleural bristles present; oral margin receding, as in Anorostotna. {johnsoni, Mass.) ...... Porsenus Darl. A humeral, propleural, five dorsocentral, two fronto-orbital, two sternopleural bristles present; auxiliary vein indistinct, {oregona, litorea, Oregon, Calif.) Silig"0 Aldr. The authors reject Heteromyza as of doubtful occurrence in North America, leaving all the American forms easily recognized by the pec- tinate costa. They also merge Scoliocentra into Leria, — which I doubt. Page 329, couplet 6, second line for 'pleural' read central. Page 334, couplet 13, for 'cell' read vein. Page 376, couplet 164; for '169' read 165. Mr. Townsend proposes to make the specimen illustrated in Fig. 156 the type of a new genus and species, which he will call Euepalpus flavicaiCda. For Fig. 157, he also proposes the new genus and species Eufabricia fl.avicans Towns. INDEX. Ablabesmyia, 114 Ablautus, 197 Acanthina, 171 Acanthinomyia, 388 Acanthocnema, 330 Acanthomera, 174 ACANTHOMERID^, 1 73 Acaulona, 361 Acemyia, 374 Aclialcus, 234 Achaetomus, 390 Achsetoneura, 380 Acicephala, 330 Acidia, 286 Acidogona, 287 Aciura, 286 Acnemia, 137 Acontistoptera, 239 Acorhynchus, 127 Acreotrichus, 216 ACROCERID^, 182 Acrochseta, 169 Acrocera, 185 Acrodiplosis, 128 Acrometopia, 296 Acronacantha, 356 Acrosticta, 278 Acrotaenia, 287 Actina, 168 Actora, 323 Admontia, 363 Aedes, 108 Aedomyia, 107 Aenigmatias, 239 Agathomyia, 243 Ag07iosoma, 232 Agromyza, 295 Agromyzid^, 291 Akronia {Alisonia) , 171 Alasion, 116 Aldrichia, 214 Allognosta, 168 AUograpta, 255 Allopogon, 201 Allophyla, 325 Allotrichoma, 307 Alophora 361, 378 Amalopis, 90 Amobia, 377 Amphicnephes, 275 Amphicosmus, 216 Anacampta, 276 Anaclinia, 138 Analcocerus, 170 Anarmostus, 204 Anastcechus, 215 Anastrepha, 283 Anatopynia, 113 Andrenosoma, 389 Anepsius, 233 Anisia, 367, 379 Anisomera, 90 Anisotafnia, 215 Anopheles, 107 Anorostoma, 325 Anthalia, 225 Anthepiscopus, 225 Anthomyia, 335 AnThomyid^, 331 Anthrax, 214 Antocha, 88 Aochletus, 171 Apalocnemis, 226 Apatolestes, 180 Aphestia, 202 Aphiochseta, 238 Aphoebantus, 217 Aphrosylus, 233 Aphria, 372 Apinops, 365 Apiocera, 189 Apiocerid^, 188 Apocephaltis, 238 Apoinidas, t88 Apophorhynchus, 281 Aporia, 379 Appeleia, 185 Aprionus, 130 Aptilotus, 316 Araba, 375 391 392 NORTH AMERICAN DIPTERA. Arcliilestris, 198 Archytas, 577 Arctobiella, 296 Arctophila, 257 Argyra, 234 Arnoldia, 128 Arribalzai(ia, 188 Arthroceras, 162 Arthrocnodax, 128 Arthropeas, 162 Asemosyrphus, 258 Asilus, 203 AsiLii)^, 192 Asindulum, 137 Asphondylia, 126 Aspistes, 144 Asteia, 302, 312 Astrophanes, 214 Asynapta, 129 Asyndetus, 233 Atacta, 372 Atarba, 88 Ateloglossa, 355 Atherix, 163 Athyroglossa, 307 Atomosia, 202 Atonia, 202 Atractia, 203 Atricliopogon, 116 Atropharista, 380 Atrophopalpus, 363 A ty lotus, 181 Aulacigaster, 295 Automola, 276 Azelia, 336 Baccha, 254 Baldratia, 127 Balioptera, 298 Baryphlegma, 287 Bathydexia, 354 Baumhaueria, 372 Belvosia, 372 Beris, 168 Berismyia, 168 Beskia, 371 Besseria, 377 Bezzia, 116 Bibio, 143 Bibiocephala, 151 Bibiodes, 143 BiBiONiD^, 140 Bicellaria, 225 Biomyia, 373 Bischofia, 323 Bittacomorpha, 91 Blastocera, 172 Blepharepiuni, 201 Blepharipeza, 374 Blepharocera, 151 Blepharocerid^, 148 Blepharoneura, 287 Blepharoprocta, 224 Bogeria, 347 Bolbomyia, 163 Boletina; 138 Bolitophila, 136 Bolomyia, 373 BoMBYi^iiD^, 210 Bombyliomyia, 377 Bombylius, 215 BoRBORiD^, 315 Borborus, 316 Boreodromia, 223 Brachycampta, 139 Brachycoma, 375 Brachydeutera, 309 Brachyneura, 130 Brachyopa, 256 Brachyophyra, 334 Brachypalpus, 259 Brachypremna, 91 Brachystoma, 224 Brachypteromyia, 383 Bremia, 128 Briciiinia, 275 Briciniella, 275 Bryocrypta, 129 Bryomyia, 130 Bucentes, 371 Cacodaemon, 199 Cacomyia, 109 Cacosis, 171 Cacoxenus, 296 Csenia, 309 Callicera, 252 Callimyia, 243 Callinicus, 201 Calliphora, 343 Callopistria, 277 Calobata, 266 INDEX. 393 Calodexia, 357 Calotarsa, 243 Camarona, 355 Campeprosopa, 170 Campsicnemus, 235 Camptocladius, 115 Camptomyia, 129 Camptoneura, 276 Campylomyza, 127, 130 Canace, 306 Caricea, 336 Cardiacephala, 266 Carphotricha, 287 Catocha, 127 Cecidomyia, 126 Cecidomyid^, 117 Celatoria, 369 Cellia, 108 Ceratitis, 283 Ceratobarys, 312 Ceratocystia, 109 Ceratogopsis, 199 Ceratolophus, 116 Ceratomyiella, 363 Ceratomyza, 295 Ceratopogon, 115 Ceraturgus, 199 Ceria, 252 Ceriogaster, 257 Ceroplatiis, 137 Cerotainia, 202 Cerozodia, 81 Cephalia, 275 Cephenomyia, 347 Cestonia, 377 Chaetoclusia, 320 Chaetogsedia, 376 Chaetogena; 377 Chsetoglossa, 372 Chcetona, 330, 356 Chaetophleps, 365 Chsetoplagia, 375 Chaetopsis, 278 Chalarus, 245 Chalcomyia, 253 Chamsesyrphus, 255 Charadrella 336 Chastnatonotus, 114 Chelipoda, 223 Chersodromia, 223 Chilosia, 253 Chionea, 86 36 Chiromyza, 168 Chironomus, 115 Chironomid^, 1 10 Chloroprocta, 342 Chlorops, 313 Cholomyia, 356 Chordonota, 170 Chorisops, 388 Choristoma, 236 Choristoneura, 127 Chortophila, 336 Chrysoceria, 201 Chrysochlafnys, 259 Chrysochlora, 171 Chrysochroma, 169 Chrysogaster, 233 Chrysomyia, 342 Chrysomyza, 278 Chrysopila, 163 Chrysops, 180 Chrysotimus, 234 Chrysotoxum, 252, 257 Chrysotus, 235 Chyliza, 268 Cistogaster, 361 Cladochseta, 302 Cladodromia, 223 Cladura, 88 Clausicella, 365 Clinocera, 224 Clinodiplosis, 129 Clinogaster, 372 Clinoneura, 357 Clinopea, 343 Clinorhyncha, 126 Clinorhytis, 129 Clista, 367 Clitellaria, 171 Clytiomyia, 371 Clusia, 320 Clusiodes, 320 Cnephalia, 378 Coeloglutus, 233 Ccelometopia, 279 Coelomyia, 336 Ccelopa, 317 Ccenomyia, 162 Coenosia, 336 Coloboneura, 223 Colomyia, 129 Colpodia, 126 Comoptera, 238 394 NORTH AMERICAN DIPTERA. Comotacta, 374 Comyops, 357 Conchy Hastes, 159 Condidea, 257 Coniceps, 279 Conicera, 238 CONOPiD^, 261 Conops, 263 Contarina, 129 Copestylum, 256 Cophura, 201 Coquillettia, 214 Coquillettidea, 109 Cordyligaster, 356 Cordylura, 330 CORDYIyURID^, 327 Corethra, 107 Corethrella, 107 Corynoneura, 114 Cricotopus, 115 Crioprora, 259 Criorhina, 259 Cryptochaetum, 295 Cryptolabis, 88 Cryptomeigenia, 363 Cryptopalpus, 377 Ctenophora, 91 Culex, 108 Culicelsa, 109 Culicada, 109 Culicella, 109 CuiviciD^, 86 Culicoides, 116 Culiseta, 108 Cuphocera, 377 Curtonotum, 302 Cuterebra, 347 Cycloleppteron, 108 Cylindrotoma, 90 Cynipimorpha, 172 Cynomyia, 342, 350 Cyphomyia, 170 Cyrtid^, 182 Cyrtometopia, 279 Cyrtoneurina, 343 Cyrtophlebia, 372 Cyrtopogon, 200 Cyrtosoma, 357 Cystiphora, 128 D Dactylocladius, 115 Daeochseta, 377 Dalmannia, 263 Damalis, 198 Dasylechia, 203 Dasyllis, 203 Dasyneura, 128 Dejeania, 377 Deiuocerites, 107 Demoticus, 375 Derraatobia, 347 Deromyia, 201 Desmatomyia, 217 Desmatoneura, 217 Desmometopa, 295 Dexia, 355 Dkxiid^, 352 Dexiopsis, 336 Dexiosoma, 357 Diachlorus, 181 Diacrita, 276 Diadocidia, 136 Diallactes, 129 Dialineura, 387 Dialysis, 163 Diamesa, 114 Diaphoropeza, 379 Diaphorus, 235 Dicranomyia, 87 Dicolonus, 200 Dichaeta, 307 Dichelacera, 181 Dichocera, 376 Diclisa, 180 Dicranophora, 169 Dicranoptycha, 88 Dicranota, 90 Dicrodiplosis, 128 Dictanus, 197 Didynia, 367 Dilophus, 143 Dioctria, 200 Dionaea, 369 Diostracus, 234 DiOPSiD^, 314 Diotrepha, 88 Dipalta, 214 Diplosis, 126 Dirhiza, 126 Discobola, 87 • Discocerina, 307 Discomyza, 307 Ditomyia, 137 INDEX. 395 Dixa, 95 DixiD^, 94 Dizonias, 199 Docosia, 138 Dolicocephala, 224 Dolichogaster, 191 Dolichoglossa, 335 Dolichomyia, 217 Dolichopeza, 91 DoiviCHOPODiD^, 228 Dolichopus, 232 Doliosyrphus^ 256 Doryclus, 202 Drapetis, 223 Drepanoglossa, 380 Drosophila, 302 DrOvSOPHII^id^, 299 Dry om via, 128 Dryomyza, 323 Dynatosoma, 137 E Eccoptomera, 326 Eccritosia, 203 E ecu lex, 109 Echinodexia, 357 Echthodopa, 200 Echinomyia, 377 Ecitomyia, 238 Eclimus, 216 Ectecephala, 312 Ectyphus, 191 Elachipalpus, 376 Elachiptera, 312 Elephantomyia, 87 Elliponeura, 312 Elliptera, 88 Eliozeta, 377 Empeda, 819 Empidid^, 218 Empimorpha, 226 Enipis, 226 Endaphis, 128 Ensina, 287 Epacmus, 217 Epalpus, 377 Ephydra, 309 Eph'ydrid^, 303 Epicypta, 138 Epidapus, 139 Epidosis, 126 Epigrimyia. 371 Bpiphtagma, 89 Epiplatea, 279 Epochroa, 286 Erax, 203 Eremomyia, 335 Eretmoptera, 113 Eriocera, 90 Erioptera, 88 Eristalis, 256 Ervia, 365 Erythrandra, 350 Euantha, 356 Euaresta, 287 Eucessia, 217 Euchaetogyne, 357 Eviclytia, 380 Eucnephalia, 377 Eudexia, 357 Eudicrana, 137 Eugnoriste, 139 Eujurinia, 380 Eulasiona, 363 Eulonchus, 185 Eumetopia, 278 Euparhyphus, 171 Eupeodes, 255 Euphara, 278 Euphantopteryx, 379 Euphorocera, 374 Eurina, 313 Eurosta, 287 Eurycephala, 277 Euryceromyia, .365 Eurycnemus, 115 Euryneiira, 171 Euryomyia, 336 Euscopolia, 371 Eusiphona, 295 Eustalomyia, 335 Eutanypus, 114 Eutarsus, 235 Euthera, 374 Euthyneura, 225 Euthyprosopa, 375 Eutreta, 287 Eutrixa, 369 , Euxesta, 278 Evibrissa, 377 Exechia, 139 Exepacnins, 216 Exorista, 374 Exoristoides, 373 Exoprosopa, 214 396 NORTH AMERICAN DIPTERA. F Feltidia, 109 Ferdinandea, 259 Firenia, 130 Forcipomyia, 116 Frontina, 374 Fucellia, 336 G Gastrophilus, 346 Gaediophana, 377 Gsediopsis, 376 Gastrops, 308 Gaurax, 312 Geminaria, 216 Gkomyzid^, 297 Geosargus, 169 Geranomyia, 87 Geroti, 217 Ginglimyia, 371 Glaurotricha, 257 Glutops, 162 Gnophomyia, 89 Gnorista, 137 Gonia, 376 Goniochseta, 371 Goniops, 180 Gonomyia, 89 Graphomyia, 343 Griphoneura, 290 Gymnochaeta, 373 Gymnoclytia, 378 Gynmodexia, 355 Gyinnometopa, 109 Gymnomma, 376 Gymnophania, 361 Gymnophora, 238 Gymnopternus, 233 Gymnosoma, 361 H Habropogon, 200 Hadromyia, 259 Hsemagogus, 108 Haematobia, 342 Haematopota, 180 Hammerschmidtia, 256 Hammomyia, 336 Haplomera, 226 Harmandia, 129 Heleodromia, 224 Helicobia, 351 Heligmoneura, 204 Helobia, 89 Helomyza, 325 Helophilus, 258 Hemerodromia, 223 Hemeromyia, 295 Hemichlora, 342 Hemithrixion, 377 HeIwOmyzid^, 324 Hemyda, 363 Henicomyia, 207 Hercostomus, 233 Hermetia, 171 Hesperempis, 226 Hesperinus, 143 Hesperodes, 143 Hesperomyia, 350 Heteracantha, 168 Heteringomyia, 320 Heterocheila, 323 Heterochroa, 298 Heteromyia, 116 Heteromyza, 326 Heteroneura, 320 Heteroneurid^, 318 Heteropeza, 126, 130 Heteropogon, 201 Heteropteriua, 371 Heterostylum, 215 Hexachaeta, 283 Hexamitocera, 330 Hiatus, 276 Hilara. 226 Hilarella, 376 Hilarenipis, 226 Hilarimorpha, 157, 163, 218 Himantostoma, 377 Himeroessa, 275 Hippelates, 312 HiPPOBOSCiD^, 382 Hirmoneura, 187 Histiodroma, 169 Holcocephala, 200 Holoneurus, 129 Holopogon, 200 Holorusia, 91 Homalomyia, 334 Homodexia, 357 Homogenia, 361 Hoplogaster, 336 Hormomyia, 126 Horniopeza, 224 INDEX. 397 Houghia, 374 Hyadesimyia, 343 Hyadina, 308 Hyalomyodes, 369 Hyalurgus, 367 Hybos, 224 Hydrellia, 308 Hydrina, 308 Hydromyza, 330 Hydrophoria, 334 Hydrophorus, 234 Hydrotsea, 334 Hyetodesia, 334 Hylemyia, 335 Hypantrophaga, 374 Hyperalonia, 214 Hypertophorocera, 377 Hypocera, 238 Hypochseta, 365 Hypocharassus, 234 Hypoderma, 347 Hypostena, 367 Hystricia, 377 Hystrisiphona, 354 Icterica, 287 Idana, 276 Idioplasta, 99 Ilythea, 307 Isoglossa, 371 Isoplastus, 114 Isostoniyia, 109 Iteaphila, 226 Janetiella, 128 Janthinosoma, 109 Joantiisia, 130 Joblotia, 108 Johannseniella, 116 Johnsonia, 350 Jurinella, 377 Jurinia, 377 Lamprempis, 225 Lampria, 203 Laphria, 203 Laphystia, 199 Lasia, 185 Ivasiona, 363 lyasioneura, 365 Lasiopogon, 200 Lasiops, 335 Lasioptera, 126 Lasiopteryx, 127 Ivasiosoma, 136 Lastaurus, 201 Lauxania, 290 Ivcia, 137 Ledomyia, 130 Lepidanthrax, 215 Lepidophora, 216 Lepidoplatys, 109 Ivcpidoselaga, 181 Ivcpidostola, 252 Lepromyia, 252 IvEPTiD^, 157 lyCptis, 163 Leptocorypha, 232 Leptoda, 356 Leptogaster, 197 Leptoruorphus, 138 lycptoraydas, 191 lyeptopeza, 225 Leptopteromyia, 195 Leria, 326 Iveskiamima, 365 Lestiocampa, 108 Lestodiplosis, 129 Lestomyia, 201 Lestremia, 127 Leptorethuni, 232 Leptosyna. 130 Leucomelina, 334 Leucophenga, 302 Ivcucopis, 296 Leucostoia, 235 Leucostoma, 369 Leucozona, 255 Limatiis, 108 Liancalus, 234 Lininobia, 87 Limnophila, 89 Limnophora, 334 lyimnospila, 336 Liniosina, 316 Liogma, 90 Lipochseta, 306 lyipoptena, 383 Linnsemyia, 373 Lispa, 336 Ivispidia, 365 398 NORTH AMERICAN DIPTKRA. Loewiola, 129 Lonchsea, 290 Lonchoptera, 240 LONCHOPTERID^, 240 Ivongurio, 91 Lophoteles, 172 Lordotus, 216 Loxocera, 268 L/ycastrirhyncha, 266 Ly per OS a, 2,42 Ivytogaster, 308 Lucilia, 343 Lutzia, 108 M Machimus, 204 Macquartia, 367 Macrocera, 136 Macrodiplosis, 129 Macrolabis, 127 Macromeigeuia, 373 Macro metopa, 256 Macrosargus, 169 Mallophora, 203 Mallota, 258 Mancia, 214 Manota, 135 Mansonia, 107 Masicera, 375 Masistylum, 377 Massalongia, 128 Mauromyia, 363 Maytiola, 128 Medeterus, 213 Medina, 365 Megamerina, 268 Megametapon, 256 Megaparia, 355 Megapoda, 202 Megaprosopus, 355 Megarhinus, 107 Megerlea, 355 Meghyperus, 224 Megistocera, 91 Megistopoda, Megophthalma, 330 Meigenia, 363 Meigeniella, 363 Melaleuca, 356 Melanodexia, 355 Melanophora, 355 Melanophyra, 373 Melanostoma, 254 Melieria, 276 Melophagus, Merapioidus, 259 Meriana, 377 Merodon, 258 Meromacrus, 256 Meromyza, 313 Merosargus, 169 Mesembrina, 243 Mesembritiella, 342 Mesochaeta, 367 Mesorhaga, 232 Mesogranima, 255 Metacosmus, 217 Metachseta, 375 Metachela, 223 Metadexia, 356 Metadoris, 377 Metaphragma, 207 Metaphyto, 374 Metaplagia, 372 Metapogon, 200, 201 Metatrichia, 209 Metopia, 376 Metopina, 238 Metriocnemus, 115 Miaster, 126 Micr cedes, 109 Michrochaetina, 355 Microchysa, 169 Microdon, 252 Microdira, 377 Microdromia, 223 Micromyia, 127, 130 Micropeza, 266 MlCROPEZiD^, 264 Microphorus, 225 Microphthalmia, Microprosopa, 330 Microsniia, 225 Microstylum, 198 Mikiola, 128 Milesia, 256 Milichia, 295 Milichiella, 295 Miltogramma, 375 Misgomyia, 387 Mixogaster, 252 Mochlonyx, 107 MochlOvSoma, 354 MochlostyraXy 109 INDEX. 399 Monardia, 130 Monarthropalpus, 128 Mongoma, 89 Molophilis, 88 Molynocoelia, 286 Morellia, 343 Morinia, 357 Morphomyia, 356 Mosillus, 307 Musca, 343 MusciD^, 337 Muscina, 343 Muscopteryx, 375 Mutiloptera, 387 Mycetobia, 136 Mycetaulus, 270 Mycetophila, 137 Mycetophii^id^, 131 Mycodiplosis, 128 Mycothera, 139 Myelaphus, 199 Myeunis, 277 Mydaea, 334 Mydaid^, 190 Mydas, 191 Myocera, 354 Myiochrysa, 169 Myolepta, 253 Myomima, 354 Myospila, 343 Myothiria, 369 Myopharus, 369 Myophasia, 363 Myoscotiptera, 354 Myopa, 263 Myrmecomyia, 275 Mystacella, 377 Mystacomyia, 373 Mythicomyia, 218 Myxosargus, 170 Myzoniyia, 108 N Nseria, 365 Napomyza, 294 Nausigaster, 253 Nebritus, 207 Nematoproctus, 234 Nemopoda, 270 Nemoraea, 373 Nemestrinid^, 186 Neoascia, 254 Neoaspilota, 287 Neochauna, 172 Neocota, 225 Neoculex, 109 Neoempheria, 136 Neoexaireta, 168 Neofischeria, 380 Neoglaphyroptera, 137 Neodiotypa, 179 Neoitamus, 204 Neophyto, 379 Neoplasta, 223 Neoroudania, 170 Neotractocera, 377 Nephrocerus, 245 Nerius, 266 Neurigona, 234 N^uroctona, 323 Nicocles, 201 Nostima, 308 Nothra, 185 Nothomyia, 169 Nothosympycnus, 235 Notiphila, 307 Notogramma, 278 Nototricha, 108 Nusa, 203 Nycteribia, 386 Nycteribiid^, 386 O Occemyia, 263 Ochthera, 308 Ochtheroidea, 308 Ochthiphila, 296 Ocnaea, 185 Ocydromia, 225 Ocyptamus, 254 Ocyptera, 372 Octodiplosis, 128 Odinia, 296 Odontomyia, 170 Odontonyx, 139 Odontopoda, 138 CEcacta, 116 CEcothea, 326 O^dalia, 224 CEdamagena, 347 O^daspis, 286 CEdicarena, 286 CEdiniapeza, 379 CEdopa, 277 CEstrophasia, 369 400 NORTH AMERICAN DIPTERA. CEstrus, 347 Olbiogaster, 156 Olfersia. Oligarces, 130 Oligotrophus, 128 Ominatius, 203 Omomyia, 317 Oncodes, 185 Oncodocera, 216 Onesia, 350 Ophthalmoinyia, 295, 390 Opsebius, 185 Odsidia, 376 Opsio^nyia, 330 Oreogeton, 225 Oreothalia, 224 Orimarga, 88 Ornithoctena, 383 Ornithodes, 90 Ornithoica, 383 Ornithomyia, 383 Ornithopertha, 383 Orphnephila, 154 Orphnephii^id^, 153 Ortai^idid^, 271 Orthochseta, 330 Orthocladius, 115 OsciN'iD^, 310 Oscinia, 312 Ospriocerus, 198 Ostracocoelia, 275 Oxycera, 171 Ozodiceromyia, 207 P Pachycerina, 290 Pachygaster, 172 Pachymeria, 226 Pachyophthalmus, 372 Palloptera; 290 Pachyrhina, 91 Palpomyia, 116 Paltostoma, 151 Panacris, 172 Paneryma, 279 Pangonia, 180 Pantarbes, 215 Pantophthalmus, 175 Panzeria, 373 Parabombylius, 215 Parachaeta. 374 Paraclius, 233 Paracosmus, 217 Paradejeania, 377 Paradidyma, 375 Parodinia, 296 Paradyschiria, Paradmontia, 363 Parafischeria, 380 Paragsedia, 377 Paragus, 252 Paragorgopis, 277 Parahypochseta, 377 Paralimna, 308 Paralleloma, 329 Paramesochaeta, 373 Paramintho, 350 Paramyia, 294 Paranophora, 379 Paraphyto, 374 Paraplagia, 372 Paraprosena, 357 Paratissa, 367 Parasyntormon, 235 Parathalassina, 224 Paratropesa, 819 Parephydra, 307 Parepalpus, 376 Parexorista, 379 Parydra, 309 Paroedopa, 277 Peckia, 350 Fedicella, 172 Pedicia, 90 Pegomyia, 335 Pelagomyia, 171 Pelastoneurus, 232 Pelatachina, 367 Pelateria, 377 Pelecocera, 252 Pelina, 308 Pelomyia, 295, 307 Pelorempis, 107 Peloropeodes, 233 Pentacricea. 336 Penthoptera, 90 Penthosia, 373 Peratochaetus, 298, 330 Pericoma, 93 Pero, 130 Peromyia, 130 Peronyma, 286 Perrisia, 127 Peteina, 377 Phalacrocera, 90 INDEX. 401 Phalacromyia, 257 Phaonia, 334 Phasioclysta, 379 Phasiops, 356 Pheneus, 163 Phlebotomus, 93 Philonicus, 204 Philopota, 185 Philorus, 151 Phoneutisca, 223 Phoniomyia, 108 Phora, 238 Phorantha, 361 Phorbia, 336 Phorichseta, 375 Phorid^, 236 Phormia, 343 Phorocera, 374 Phorostoma, 355 Phortica, 301 Phronia, 138 Phthinia, 138 Phthiria, 216 Phycodromid^, 317 Phylarchus, 234 Phyllogaster, 336 Phyllolabis, 89 Phyllomyza, 296 Phylomidas, 191 Phylygra, 308 Phyra, 334 Physocephala, 263 Physogenua, 290 Phyto, 363 Phytomyza, 294 Pialeoidea, 185 Piophila, 270 PiOPHiiviD^, 269 Pipiza, 252 PiPUNCULiD^, 244 Pipunculus, 245 Pityocera, 180 Plagia, 371 Plagiomima, 371 Plagioneura, 232 Plagiotoma, 286 Plagiprospherysa, 372 Plastophora, 238 Platophrymyia, 295 Platychirus, 254 Platycnema, 243 Platymochaetus, 257 Platy palpus, 222 Platypeza, 245 Pl^ATYPEZiD^, 241 Platystoma, 275 Platyura, 137 Plecia, 142 Plectops, 365 Plectromyia, 90 Plesiastina, 137 Plesiomma, 200 Plethochaeta, 330 Ploas, 216 Pneuniaculex , 108 Pocota, 259 Pogonomyia, 334 Pogonosoma, 202 Pogonota, 330 Polidea, 367 Polinota, 283 Pollenia, 342 Porphyrops, 235 Porsenus, 390 Polyangaeus, 90 Polydontomyia, 258 Polygaster, 367 Polylepta, 136 Polymedon, 233 Polymera, 88 Polymorphomyia, 286 Polystepha, 128 Priomerus, 256 Prionellus, 130 Probezzia, 116 Probolaeus, 135 Procladius, 113 Prochyliza, 270 Proctacanthus, 203 Prodiamesa, 114 Prolepsis, 199 Promachus, 203 Promeranisa, 170 Prorates, 224 Prorhynchops, 354 Prosalpia, 336 Prosena, 354 Prosenoides, 354 Prospherysa, 375 Protanypus, 113 Protenthes, 387 Protocalliphora, 343 Protoculex , 109 Psairoptera, 277 402 NORTH AMERICAN DIPTERA. Pseclrocladius, 115 Pselaphila, 329 Pseudapinops, 365 Pseudiastata, 390 Pseudochseta, 374 Pseudociilex, 109 Pseudodexia, 357- Pseudodinia, 296 Pseudolfersia, 383 Pseudomorina, 357 Pseudopyrellia, 343 Pseudorus, 202 Pseudotephritis, 277 Psendotrichia, 209 Pseudotractocera, 373 Psila, 268 PsiiviD^, 267 Psilocephala, 207 Psilocurus, 199 Psilopa, 307 Psilopodinus, 222 Psilopus, 232 Psilotanypus, 113 Psilota, 253 Psorophora, 108 Psychoda, 93 PSYCHODID^, 92 Ptecticus, 169 Pterallastes, 257 Pterellipsis, 385 Pterocella, 277 Pterodontia, 185 Ptilodexia, 356 Ptilodegeeria, 367 Ptilomyia, 307 Ptiolina, 163 Ptychoptera, 91 Puliciphora, 238 Putoniella, 128 Pycnoglossa, 330 Pycnopogon, 200 Pyrellia, 343 Pyrgota, 274 Pyritis, 357 Pyrophaena, 253 Racodineura, 368 Rhabdopselap I121S , 217 Rhachicerus, 162 Rhadiurgus, 204 Rhagoletis, 286 Rhamphidia, 87 Rhamphinina, 357 Rhaniphomyia, 225 Rhaphiocera, 169 Rhaphidolabis, 90 Rhaphiomidas, 188 Rhaphirhynchus, 174 Rhaphium, 235 Rhombothyria, 357 Rhopalomera, 281 Rhopai^omerid^, 280 Rhopaloniyia, 128 Rhopalosyrphus, 252 Rhicnoessa, 296 Rhingia, 256 Rhingiopsis, 179 Rhinophora, 363, 379 Rhinotora, 281 Rhipidia, 87 Rhyniosia, 139 Rhynchocephalus, 186 Rhynchodexia, 354 Rhynchosciara, 139 Rhyphid^, 155 Rhyphus, 155 Rhypholophus, 88 Rhysops, 253 Richardia, 279 Rileymyia, 378 Rivellia, 275 Roederiodes, 223 Ruebsaamenia, 129 Runchomyia, 108 S Sabethes, 108 Salpingogaster, 254 Sapromyza, 290 Sapromyzid^, 288 Sarcionus, 232 Sarcoclista, 363 Sarcomacronychia, 380 Sarcophaga, 351 Sarcophagid^, 348 Sarcophagula, 351 Sarcophilodes, 350 Sardiocera, 356 Sargus, 169 Saropogon, 201 Sayoniyia^ 107 Scaeva, 255 Scatella, 309 INDKX. 403 SCATOMYZID^, 327 Scatophaga, 329 SCATOPHAGID^, 327 Scatopse, 143 Scellus, 234 SCKNOPINID^, 208 Scenopinus, 209 Schizomyza, 128 Schizotachina, 375 Schoenomyza, 336 Sciara, 139 Sciasma, 369 Sciomyza, 323 SciOMYZiD^, 321 Scione, 180 Sciophila, 136 Scleropogon, 198 Scoliocentra, 325 Scoliopelta, 171 Scotiptera, 354 Senobasis, 201 Senogaster, 258 Senoprosopis, 204 Senotainia, 373 Seoptera, 278 Sepedon, 323 Sericomyia, 257 Serromyia, 116 Skpsid^, 269 Sepsis, 270 Sepsisoma, 278 Sicus, 263 Sigaloessa, 302, 312 Sigmatomera, 88 Siligo, 390 Silvius, 180 SlMULIID^, 144 Siniulium, 147 Siphona, 371 Siphonella, 312 Siphoplagia, 371 Siphosturmia, 373 Snowielhis, 181 Somomyia, 343 Spallanzania, 376 Spania, 163 Spaniocera, 125 Sparnopolius, 216 Spathiophora, 330 Sphserina, 367 Sphserocera, 316 Sphaeromyas, 116 Sphaerophoria, 255 Sphageus, 198 Sphecomyia, 259 Sphegina, 254 Sphenoidoptera, 216 Sphyracephala, 314 Sphyximorpha, 252 Spilochroa, 298, 320 Spilogaster, 334 Spilographa, 286 Spiloniyia, 259 Spogostylum, 214 Spyridopa, 172 Stegana, 301 Stegomyia, 108 Steneretma, 279 Stenodexia, 356 Stenodiplosis, 129 Stenomacra, 279 Stenomicra, 302 Stenomyia, 278 Stenopa, 286 Stenopogon, 188 Stenopterina, 275 Stenoxenus, 113 Stevenia, 377 Stibasoma, 181 Stichopogon, 200 Stictomyia, 277 Stilbometopa, Stilpnogaster, 204 Stilpon, 223 Stomoxys, 342 Stratiomyia, 170 StraTiomyid^, 164 Straussia, 286 Strebla, 385 Strkbi^id^, 384 Stomatodexia, 355, 380 Strobliella, 127 Stygeropis, 91 Stylogaster, 263 Sycorax, 93 Symballophthalmus, 222 Symphoromyia, 163 Synipycnus, 235 Syndyas, 224 Syneches, 224 Syneura, 238 Synthesiomyia, 342 Syntemna, 138 Syntormon, 236 404 NORTH AMERICAN DIPTKRA. Syritta, 255 Syrphid^, 246 Syrphus, 255 Systoechus, 215 Systropus, 217 Tabanus, 181 Tabanid^, 176 Tabuda, 207 Tachina, 375 Tachinid^, 358 Tachinomyia, 378 Tachinopsis, 375 Tachydroinia, 223 Tachypeza, 222 Tachytrechus, 233 Taeniorhynchus, 108 Tanpezid^, 264 Taiiypremna, 91 Tanypus, 114 Tanytarsus, 115 Taracticus, 201 Tauromyia, 298 Telmatogeton, 114 Telostylus, 266 Telothyria, 371 Temnostoma, 259 Tephritis, 287 Tephrochlamys, 325 Tephronota, 276 Tersesthes, 115 Tetanocera, 323 Tetanops, 276 Tetrachaeta, 336 Tetragoneura, 136 Tetragrapha, 377 Tetropismenus, 276 Teuchocnemis, 258 Teucholabis, 88 Teuchophorus, 235 Toreus, 226 Townsendia, 198 Toxomerus, 255 Toxorhina, 87 Toxophora, 217 Toxotrypana, 283 Thalassomyia, 114 Thecodiplosis, 129 Thecomyia, 323 Thelaira, 357 Thelairodes, 356 Theniira, 270 Theresia, 357 Thereva, 207 Therevid^, 205 Theria, 351 Therioplectes, 181 Thinodromia, 223 Thinophilus, 235 Thrypticus, 233 Thrj'ptocera, 365 Thysanomyia, 375 Tinolestes, 109 Tipula, 91 TlPUWDJ^, 81 Tragi n ops, 296 Trichina, 225 Trichobius, 385 Trichocera, 89 Trichocladius, 115 Trichogena, 376 Trichomyia, 93 Trichonta, 138 Tricophora, 377 Trichophthicus, 334 Trichopoda, 361 Trichopteromyia, 127 Trichosia, 139 Trichotanypus, 114 TricliSy 199 Tricolyga, 377 Tricopalpus, 330 Trigonometopus, 323, 321 Trimicra, 89 Trineura, 238 Triodonta, 258 Triognia, 90 Triptotricha, 163 Tritoxa, 276 Tritozyga, 127 Trixa, 363 Trixodes, 355 Trochilides, 375 Tromodexia, 355 Tropidia, 257 Tropidomyia, 262 Tropidopsis, 377 Trypeta, 286 Trypktid^, 282 Triplasius, 215 Tylomyia, 270 Tyreomma, 342 INDEX. 405 U Ula, 90 Ulidia, 278 Ulomorpha, 89 Uramyia, 356 Uranotaenia, 107 Urellia, 287 V Vanderwulpia, 369, 374 Verrallia, 245 Volucella, 256 Wasmaniella, 130 Willistoniella, 281 Willistoniiia, 389 Winnertzia, 126 Winthemia, 375 Wyeomyia, 108 X Xanionotum, 239 Xanthracrona,277 Xanthandriis, 254 Xanthina, 234 Xanthochlorus, 234 Xanthodexia, 357 Xanthogramma, 255 Xanthomelana, 369 Xanthomeianodes, 379 Xenochaeta, 287 Xiphura, 91 Xylodiplosis, 129 Xylomyia, 162 Xylophagus, 162 Xylota, 258 Zabrachia, 172 Zagonia, 298 Zacompsia, 278 Zodion, 263 Zygoniyia, 138 Zygonetira, 139 Ovi-/ BOSTON PUBLIC LIBRARY 3 9999 06607 020 0 M 1 ii i