iviobcow,, Idaho. tvl • Compliments of S. W. WilliSTON. State University, Lawrence, Kansas, U.S.A. Please acknowledge receipt. \e^ ^ MANUAL FAMILIES AND GENERA ]^roRTH American Diptera/ SFXOND EDITION REWRITTEN AND ENLARGED SAMUEL W^' WILLISTON, M.D., Ph.D. (Yale) PROFESSOR OF PALEONTOLOGY AND ANATOMY UNIVERSITY OF KANSAS AUG 2 1961 NEW HAVEN JAMES T. HATHAWAY 297 CROWN ST. NEAR YALE COLLEGE 18 96 Entered according to Act of Congress, in the year 1896, Bv JAMES T. HATHAWAY, In the office of the Librarian of Congress, at Washington. PREFACE Eight years ago the author of the present work published a small volume in which he attempted to tabulate the families and more important genera of the diptera of the United States. From the use that has been made of that work by etitomological students, he has been encouraged to believe that the labor of its preparation was not in vain. The extra- ordinary activity in the investigation of our dipterological fauna within the past few years has, however, largely destroy- ed its usefulness, and it is hoped that this new edition, or rather this new work, will prove as serviceable as has been the former one. In the present work there has been an at- tempt to include all the genera now known from north of South America. While the Central and West Indian faunas are preeminently of the South American type, there are doubt- less many forms occurring in tlie southern states that are at present known only from more southern regions. In the preparation of the work the author has been aided by the examination, so far as he was able, of extensive col- lections from the West Indies and Central America submitted to him for study by Dr. D. Sharp of Cambridge, England, and Messrs. Godman and Salvin of London, together with the extensive collections of the University of Kansas and tliose from South America in the author's private cabinet, alto- gether forming probably the largest collection of American IV PKEFACE. Diptera ever brought together. For the descriptions of the early stages reliance has necessarily been placed chiefly upon the writings of Brauer. As will be seen, assistance has been derived from the works of Schiner, Osten Sacken, Loew, Wulp, Townsend and others, although but very few of the North American genera, aside from those of the Tach- inidae and Dexiidse, are unknown to the writer. The author owes his sincerest thanks to Prof. J. M. Aldrich for the family characters and table of the Dolichopodidee ; to Prof. V. L. Kellogg for the paragraphs on the internal anat- omy of Diptera ; to Prof. J, B. Smith for kind favors ; and to Prof. W. A. Snow for the table of the Ortalidse. Lawrence, Kans., June 10, 1890. C O R 11 1 G E N D A . V Page viii, line 0, for 'writer' read student. y X, line 10, for 'hemispherical' read spherical. *<xix, line 5 from bottom, for 'Cyclorrhapha' read Orthorrhapha. «^ 18, line 2 from bottom, insert not before 'forked' and delete from the following line. *^ 81, line 4 from bottom, for 'anal cell closed' read discal cell open. ^ 82, line 2, for 'Thambeta Williston' read Diotrepha Osten Sacken. " 35, line 14, for 'a' read ;3. ^^40, line lo from bottom, insert flattened before 'cylindrical', and, three lines below, read 'tibia? with or without spurs.' •^ 4.3, last line, for 'Subula Omyia, nom. nov.' read Xylomyia IJondani. ^•OwTine 13, for 'Orthoneuromvia Williston' read Psiloclrus Loew. '64' '67' V^88, line 17 from bottom, for read 07 ; line from bottom for read 65. 00, line 15 from bottom, for 'Eumyidae' read Holometopa ; lino 11 from bottom, for 'Schizophora' read Eumyidje. y 140, line 3, for 'with' read without. TABLE OF CONTENTS. INTRODUCTION, VI TABLE OF CONTENTS. TllKHEVIlJ.K, SCENOPINin.«, ACROCERID.E, LoNCHOPTERin.E, Empidid.k, . dolichopodii)^, Syrphid.k, . conopid.e, . PlPUNCULID^, Platypezida;, Phorid.k, MUSCIDEA, . borborid.e, Agromyzid^, GeOMYZID/E, oscinid.e, Drosophilida;, Ephydrid^, DiOPSIDiE, . SePSID/E, MlCROPEZID^E, PsiLlD.Ti, Ortalid^>, . Trypetid^e, Sapromy'zid^, Rhopalomerid/E Helomy'zid.*:, Heteroneurid^, Sciomyzida;, Phycodromiu^, scatomyzid.e, Anthomyid.k, OeSTRII)^, . Sarcophagid^, MUSCID.E, TACHINIDiE, Dexiid.1';, HlPPOBOSCIDiE, Nycteryiuii)^, APPENDIX, INDEX, INTRODUCTION The order of two winged insects, known as flies or Diptera, includes nearly forty thousand known species from different regions of the world. As many of the species are very small, often minute, and inconspicuous, and as the order has received only a small share of the attention of collectors and students, it is very probable that not one third of the real number in existence have yet been made known. In jSTorth America not far from four thousand species have been studied, and we doubtless have as many more awaiting discovery. The knowl- edge of the dipterological fauna has progressed with increas- ing rapidity during the past ten or twenty years, but vast fields for profitable study yet remain open for the serious in- vestigator. In North America the results to be obtained are almost inexhaustible. Nearly every family remains for the conscientious monographer. The mere making of new species is the least interesting of the work to be done, and perhaps the least profitable. At the same time the increasing litera- ture makes the determination of desultory species more and more difficult. To the amateur, beginning the study of this interesting order, some words of advice or explanation will be of service. The present work can make no pretensions to completeness in the characterization of genera, and he should never depend upon mere tables in the absence of other information. Doubt of the right generic location of a specimen may often be surest dissipated by attempting to refer to some species. Until the student has acquired a sort of intuitive acquaintance with the different families the work may he somewhat tedious, but by VIII INTRODUCTION. perseverance he can not fail to overcome whatever obstacles families and genera may present. He will be very much aided at the beginning by having a tolerably large collection at his command by which to make comparisons. Difficulties will often disappear with positive evidence before him, where negative characters are puzzling. With each genus in a fam- ily positively determined the difficulties and uncertainties of others will gradually disappear. ^ii'iuLu^ To determine his species the ^itfitcr will need access to a large number of papers, lists of which to the present time will be found in the catalogue of Osten Sacken, and on page xxxiii of the present work. There are a few masters of dipterology, and the student will never err in consulting their writings, no matter upon what subjects they may be. Of these I would especially mention Meigen, Wiedemann, Schiner, Winnertz, Loew, Osten Sacken, Brauer and Wulp. Other writers whose works are indispensable, but who are not to be trusted as guides, are Macquart, Walkei*, Rondani, Bigot, Desvoidy, etc. Of the contemporary writers whose works will be found useful, and in most cases valuable, may be mentioned Verrall, Meade, Eaton and Austen of England Bergenstamm, ; Mik, Strobl and Kowarz of Austria ; Becker, Ruebsamen, Girschner and Roeder of Germany ; Schnabl and Dziedzicki of Poland; Giglio-Tos and Bezzi of Italy; Bergroth of Finland; Skuse of Australia; the Lynchs of South America; Aldrich, Banks, Coquillett, Johnson, Scudder, Snow, Townsend and Wheeler of this country. Probably the most useful single work that tlie student will find after Osten Sacken's Cata- logue (Smithsonian Ins. 1878) is Schiner's Fauna Austriaca, and the most useful foreign periodical the Wiener Ent. Zeitung, of which the accomplished Mik is one of the editors. The Zoological Record Avill be almost indispensable in ascer- taining what has been done during the past thirty years. For the beginner I would especially recommend Comstock's Manual f(jr use in conjunction with this work. INTUODUCTIOX. IX Diptera may always be recognized by the presence of but one pair of wings ; the second pair of other insects is really represented by a small organ on eacli side back of the true wings, consisting of a short, slender stem with a knob-like ter- mination, called the halteres or poisers. Their function is not known ; that they have some function seems certain, as they are always in vibration during flight. Not all flies are winged; in some degraded forms, both among the lowest and highest groups of the order, they may be entirely wanting, as also the halteres. Sometimes the males will have wings and the females be wingless. But the number of wingless forms is very small. In the adult state the habits of flies are very various. Some, but not a very large proportion, are predaceous upon other insects, sucking their juices. Some are very annoying to man and other warm-blooded animals, sucking their blood ; of these may be mentioned the mosquitoes, black-flies, horse-flies, sta- ble and horn flies, the tsetze fly, etc., as well as all the pupipara, wliich are parasitic upon birds and mammals. By far the largest number of diptera, however, feed upon vegetable sub- stances, either fresh or decaying, the pollen and honey of flowers, etc. Some feed upon ordure and decaying material of whatever nature it may be. In the larval stages, the habits are yet more diverse. Brief references to the larval habits will be found in the following pages. Suffice here to say that tlie larger part are vegetable feeders, but not a few live uj)on decomposing animal matter, or in the living bodies of other insects, snails, reptiles, birds, nuiinmals, etc. While some members of the order may be very annoying or prejudicial to man's economy, the order, upon the whole, is a beneficial one, whether in the larval or mature stages, whether as parasites upon other, and injurious organism, or as scavengers.