a 7 ves er CN we > es os es ae & e aa A ek a a “S -~ A + eoE tA AAAS LPC PERE ES A te ~ Reins xz o~ Aetna tater * PARAS [eV Se vat x SEN RON A i Hi i Ray inf AY) oo ; x8 ayy S ORANG \ Fd aN At) : Snir AMSA a apa SEERA ee See eee ters sit ME Ri ; 0 ais it want oN) aa Pi ) ~ ae 4 Pie ie Ly Ao VAN “AGU NT OF PeltisoHn FUPRES (DIPTERA). ei BY BRED Ve TI EOBALD, BA) -Pl Biss CAMBRIDGE UNIVERSITY EXTENSION LECTURER IN INJURIOUS INSECTS, ETC. G <\ 30 Nig r\, i JUL 3 1 oa YN Be hse i SS UBRARY — . nee BS te EQS Se eae ana VODur. LONDON: PEEIOL STOCK, 62,;PATERNOSTER ROW; E.C: 1892. iy) hil Bre, vi a Fy 1 7 a Meinl 4 vo» i) Dh, ote PRE AG Ex THE reason I undertook to publish this book was the almost total absence of any treatise in English upon this much-neglected order of insects. I have dealt with most of the species indigenous to the British Isles, and with many points of general interest relating to the order of ‘ Flies,” also with the characteristics of families and genera, and, where possible, with the life histories of the various groups, especially of those that are injurious to our crops and farm stock. The only English work published on this subject is Walker's “Insecta Britannica Diptera,” which is now out of print. It was written more than fifty years ago, and naturally contains much that is quite out of date and inconsistent with the knowledge of the present day. t is hoped that this account may in some way fill up this gap in entomological literature. The author trusts he will be pardoned for the many discrepancies that may have crept in, owing in many instances to his imperfect knowledge of the languages in which most of the literature on this subject is written. For those who wish to go more fully into the subject, the larger works of Meigen (‘“ Zwei- flugelige Insecten”), Macquart (“ Dipteres exotique ”), and Schiner (“Fauna Austriaca”), together with the numerous papers, articles, and pamphlets enumerated at the end of each family, may be consulted. In a small work of this kind it is impossible to give a detailed description of all the species recorded as British. I have there- fore chosen those about which there seems no doubt, and have omitted many mentioned by Walker as being doubtful. The Iv PREEHA GE. families treated of in this volume are the most difficult and least understood of any, and are in a most unsatisfactory state with regard to their systematic arrangement and identification. It is hoped that this account may spur younger workers on to establish new and important facts, so that inaccuracies may be corrected which naturally will be found in it, and new discoveries made. I have to express my thanks to numerous entomologists for kindly help, and for lending specimens to be figured, especially to Miss Ormerod for the loan of blocks from her ‘“ Manual of Injurious Insects.” PRED. Ve Lek O BAD: CAMBRIDGE, 1892. GO Ne EN Se PREFACE = = = = ss = 5 A SHORT ACCOUNT OF THE MORE IMPORTANT CHARACTERISTICS OF THE FAMILIES OF DIPTERA = = = CHAPTER: yt. FOSSIL DIPTERA - - - : : i CHARTER SE. CLASSIFICATION OF DIPTERA, WITH AN INTRODUCTORY ACCOUNT OF THE ANCIENT AND MODERN CLASSIFICATION OF INSECTA CHARTER LIL THE APHANIPTERA, OR FLEAS - = = - - CHAPTER IV. THE CECIDOMYIDA, OR GALL GNATS = = = = CHARTER AY. THE MYCETOPHILIDA, OR FUNGUS GNATS = = = CHAPTERS Vil: THE BIBIONIDA = - - - = = THE SIMULID/Z = - - - = z CHAPTER VII. THE CHIRONOMIDA, OR MIDGES - - - - INDEX - : - - - - - - XI 21 g2 152 165 169 207 ay W 9 or Aun BPW N List Or ILCUSTRAGIONS: . Larva of Pulex felis (canis) . Pupa of P. zrritans . Imago of Pulex 9 . Head of larva of P. felis (canis) . Alimentary canal of larva . Catocha latipes - . Balancer of Cecid - . & Genitalia of a Cecid . Larva and pupa of Cecidomyia . Anchor process of Hessian Fly and Wheat Midge - . Aristolochia clematis, showing method of fertilization . Galls produced by some Cecidomyide - - . Mouth parts of AZycetid larva - 3 Larvee of Sciophila, Ceroplatus, and Sciara . Pupa of Sciara- . Alimentary canal of Mycetid larva (AZycetophila) - . Head and antenna of Asindulum, . Boletina dubia - . Three types of venation in Sciara . Wing of Bradysia - , Lpidapus venaticus 22. Wing of Zygoneura- . Mycetophila cingulum . & Genitalia of Phronia 2 Genitalia of Phronia Head of Leptomorphus Watkeri . Head of Zetragoneura Sylvatica . Sciophila Fasciata - . Ceroplatus lineatus- . Antenna of a Alacrocera and head of Sciara Vill LASL OF ALE CSIEA TIONS. FIG, PAGE 31. Bolitophila fusca - - - - : = eaealAG 32. Mycetobia pallipes (wing, leg, and palpus) - - - 148 33. Wing of Ditomyta fasctata - - - - - 149 34. Wing and palpus of Diadocidia ferruginosa : - 150 35. Dilopus febrilis, or Fever Fly - - - - 61 36. Stmulium reptans - - - - - - 168 37. Larva of Chironomus plumosus — - : - ae ie 38. Eggs of Chironomus : : : : = A 39. Pupa of Chivonomus plumosus - - - - 175 40. Clunio marinus - - . - - - 196 41. Larva of Cevatopogon bipunctatus - - = =| EO] 42. Pupa of Ceratopogon bipunctatus - - - . - 107 43. Compontia cruciformts - - - - - 202 44. Three undescribed larvee of Chironomus (sp.?) - - 204 DESCRIPTION OL LEATES, PEATE. WINGS OF SOME CECIDOMYID. 2 (=2A) Diplosis. 4 (=4a) Asynapta. 6 (=6a) Campylomyza. 8 (=8a) Colpodia. to (=10A) Lasioptera. 2. Lastoptera rubt. 4. Antenna of HW. fasciata. 6. Antenna of Campylomyza halterata. 8. Antenna of Asphondylia sarothamnt. Fic. 2. Pupa of B. pomone. 4. Wing and antenna of Scatopse. 6. Bibio marci (leg and an- tenna). 1 (=1A) Cecidomyia. Fic. 3 (=3A) Epidosis. i 5 (=5a) Catocha. ss 7. (= 7A)! Lestremia. 4 9 (=9A) Spaniocera. 5 BEAT Ey Le CECIDOMYID&. 1. Hormomyia fasciata. Fic 3. Micromyta globtfer. 33 5. Antenna of Sfidosis ,, gracilis. 7. Antenna’ of Diplosis: — ;, buxt. g. Antenna of Lestremia Carnea. PLATE TE, BIBIONIDZ. 1. Larva of 47b70 pomone. 3. Leg of Anarete ali- ,, pennis. 5. Antenna, wing, and leg __,, of Aspistes berolinensts 7. Wing, leg, and antenna of Delophus febrilis. x DESCRIPTION OF PLATES: PLATE AN. CHIRONOMIDA. Fic. 1. Corynoneura (antenna Fic, 3. Anal segment of TZany- of ¢ and ?). tarsus. » 2. Antenne of C.plumosus, ,, 5. C. plumosus. 2 ee » 4. Antenna of Diamesa ,, 6. Wing and antenna of tonsus. Lanypus monilts. », 7. Antennaof Cluniomari- ., 8. Ceratopogon ilustris. nus. » 9. AntennaofMetriocnemus ,, 10. Antenna of C. femoratus. lacustris. A SHORT ACCOUNT OF THE MORE IMPORTANT CHAR- ACTERISTICS OF THE FAMILIES OF DIPTERA. Family Pulicide. Parasitic insects, with scale-like rudimentary wings ; long legs, very large coxee, tibize spurred. Eyes may or may not be present. Thorax composed of three distinct segments. Family Cecidomyide. Ocelli often absent. Thorax with no transverse suture. Antenne moniliform, 24-jointed in ¢, 12 to 14 in the 9. Wings with only few nervures. Coxze not elongated, femora not thickened, no spurs on tibiee. Family AZycetophilide. Ocelli two or three ; often so small they can only just be discern- ible. ‘Thorax with transverse suture. Antennze usually 16-jointed. Eyes generally round. Few nervures in wings, no discal cell. Tibize spurred, coxz elongate. Family Bibionide. Ocelli three. Thorax without transverse suture, pro-thorax largely developed. Eyes of ¢ large and contiguous, smallin 9. Antenne g-jointed. No discal cell in wings. Feet armed with long em- podium, pulvilli present in some genera. Family Stmulide, Ocelli none. Thorax without transverse suture. Posterior tibize and first joint of hind tarsi dilated. Antennze cylindrical, 11-jointed. Family Chironomide. Head small, retracted; often partly covered by thorax. Ocelli none. No transverse suture on thorax. Eyes reniform. Antennze from 6 to 15 joints; pectinate in ¢, simple and composed of fewer joints in 2. Wings without vein along the posterior margin ; costal vein ending near the tip of the wing. x “SHORT ACCOUNT OF THE MORE IMPORTANT Family Orvphnephilide. Ocelli absent. Head small, round; eyes round. Costal vein continued round the posterior border of wing. Family Psychodide. Ocelli absent. Body with long, coarse hairs. No transverse suture to thorax. Antennze long, 16-jointed. Wings very broad and hairy ; many longitudinal veins, only a few transverse veins ; no dis- coidal cells. Legs long, tibize without spurs. Family Cudlicide. Ocelli none. Thorax with no transverse suture. Head small. Antenne long, 15-jointed ; pectinate in ¢. Costal vein continued round margin of wing, fringed with scales ; veins in their last sub- divisions more than six in number. Family Dixide. Ocelli wanting. Head rounded. Antenne long, 12-jointed ; basal joint thick, flagellum slender. Family Zipulide. No ocelli. Thorax with V-shaped transverse suture. Antenne long, composed of 6 to 19 joints. Basal cells of wings reaching beyond the middle. Discal cell generally present. Legs long and slender. Family Ahyphide. Ocelli three. No transverse suture on thorax. Antenne as long as thorax ; 16-jointed. Wings with a perfect discal cell, large and broad. Empodium like a pulvillus, pulvilli wanting. Family Stratiomyide. Head short, as broad as thorax. Third joint of antennz annu- lated ; furnished with a terminal bristle. Ocelli present. Three basal cells, much prolonged. Veins of two main trunks very crowded anteriorly. Costal vein reaching only to middle of wing. ‘Tibiz spurless. Empodium large, resembling pulvillus. Family Xylophagide. Head short and broad. Third joint of antennz annulated; no terminal bristle. Three basal cells, very prolonged. Third longi- tudinal vein furcate; both intercalary veins present. Marginal vein encompassing the whole wing. ‘Tibice with spurs. Empodium as above. CHARACTERISTICS OF FAMILIES OF DIPTERA. xis Family Zabanide. Three basal cells, very prolonged. Third longitudinal vein furcate. Two intercalary veins always present; marginal running around whole border. Tegule large. Head broader than thorax. Third joint of antennz annulate, generally entire; no terminal bristle. Proboscis strong and prominent. Empodium large, pulvilliform. Family Lepitide. Head smaller than in Tabanide. Antennz short, last joint rounded, furnished with terminal bristle. Family Aside. Three basal cells, much prolonged. Third longitudinal vein furcate, and the two intercalary veins present. Head short and broad; eyes prominent. Third joint of antenne simple. Thorax narrowed in front. Empodium like a horny bristle. Family Bombyiide. Three basal cells much prolonged; the anterior intercalary present, the posterior always wanting. Proboscis prominent, long and slender. Third joint of antennz simple, generally provided with a bristle or tuft at the end. Empodium rudimentary. Family Zherevide. Three basal cells prolonged; both intercalary veins present. Third longitudinal vein furcate. Antennze with short terminal bristle. No empodium. Family Scenopinide. Three basal cells, very large ; the third closed far from the border of wing. No intercalary vein; third longitudinal vein furcate. Antenne with third joint very long, no terminal bristle. No em- podium. Family Cyrtide. Eyes very large. ‘Tegule vaulted, very large. Basal cells long. Neuration very variable, often incomplete. Terminal antennal joint simple. ‘Tibiz spurless. Empodium large, pulvilliform. Family Lmpide. Three basal cells complete, large ; the third shorter than second. Posterior basal transverse vein parallel to border of wing. Anterior intercalary present, posterior wanting. Antenne with first two joints very small, hardly distinct; third not annulated ; often with a ter- minal bristle. LEmpodium membranaceous. xy SOL ACCOUNT OF THEIMORE TUPORTANT Family Dolichopodide. First basal cell rather short, the second united with discal cell, third small. Auxiliary vein running in the first longitudinal. Third vein simple; fourth often furcate. No intercalary vein. Em- podium small, membranous. Antennze close together ; third joint not annulated, with bristle at tip. Family Lonchopteride. Three basal cells of moderate size, nearly equal in length. Fourth longitudinal vein furcate, and united with fifth near the base. First two joints of antennze small, testaceous ; third rounded, with a slender apical bristle. Empodium wanting. Family Platypezide. Three basal cells rather large, the hindermost always ending acutely at more or less distance from the border of the wing. Third longitudinal vein simple. No intercalary vein. Antenne with apical bristle. Empodium wanting. Family Pipunculide. Three basal cells much prolonged, the hindermost closed near the border of the wing. Fourth vein may be absent, furcate when present. No intercalary vein. Eyes large, not quite contiguous in g. Antenne short, with a basal bristle. Legs with few short spines. Empodium wanting. Family Syrphide. Three basal cells much prolonged. Third longitudinal vein simple ; a spurious longitudinal vein between third and fourth ; fourth united at its end to the third ; no intercalary veins. Antenne close together ; third joint various, generally compressed and with a bristle on its back. Hypopygium unsymmetrical. No empodium Head semicircular, as broad as thorax. Family Conopide. Three basal cells, large, third closed, more or less remote from the posterior border. All the longitudinal veins simple; no intercalary vein. Head large, always broader than thorax. Antenne long ; third joint clubbed and ending in a bristle. Hypopygium symmetrical. Em- podium wanting. Proboscis generally prolonged. Eyes not con- tiguous. Family stride. Antenne inserted in round pits. Oral organs rudimentary. Tegule large. Antenne short; third joint with a terminal bristle. Very hairy flies, resembling bees. CHARACTERISTICS OF FAMILIES OF DIPTERA. xv Family Zachinide. Antennal bristle bare, or covered with minute pubescence. Thorax short. First posterior cell closed, or only faintly open. Abdomen more or less oval, beset with bristles. Legs short. Family Dexide. Antennal bristle hairy or pectinated. Thorax short. First pos- terior cell as above. Tegulz large. Abdomen with long bristles on at least the last two segments. Legs long. § Family Sarcophagide. Antennal bristle plumose or hairy ; apex bare. First posterior cell as above. Tegulz large. Legs stout. Family AZuscde. Antennal bristle entirely plumose or pectinated. Body stout, thorax short. First posterior cell only slightly opened or else closed at the border of the wing. Family Anthomyide. Antennal bristle naked or pectinated. Thorax with a complete transverse suture. First posterior cell fully open. Tegulze not very large. Abdominal bristles often absent. Family Cordyluride. Neuration complete. Both posterior basal cells large. Auxiliary separated from the first longitudinal vein. Whole lateral border of the front bristly ; anterior border of mouth with numerous strong vibrissz. Family Phycodromide. Front bristly ; border of the mouth hairy, with no distinct vibrissee. Legs stout ; tibiz with spurs, and each with a small bristle on the outside, near the tip; the first joint of posterior tarsi not abbreviated ; last joint of all the tarsi enlarged, with stout claws and long pulvilli. Costa without bristles ; basal cells not small. Family Helomyside. Front bristly on its upper half only. A stout bristle at each side on the anterior border of mouth. Costa bristly. First longitudinal vein not abbreviated, but bare. All the tibize with spurs, and with a more or less developed erect bristle on the outside near the tip. mv, SHORT ACCOUNT Of THE MORE IMPORTANT Family Psz/de. Body elongate, with short hairs and almost without bristles. Front with only a few bristles in the neighbourhood of the crown, no bristles near mouth. Neuration complete; auxiliary vein lies close by the first longitudinal vein, but diverges from it at its end and runs towards the border of the wing; by a transverse fold, most characteristic in this family, running from tip of auxiliary vein as far as the base of the third posterior cell, the outward end of the auxiliary vein is obliterated. Posterior basal cells large. Family AZicropezide. Body slender, with short hairs and very few bristles. Neuration of veins complete ; first longitudinal vein bare ; auxiliary vein is very close by it, and diverges from it towards its end only; the two posterior basal cells very large. A few bristles on the crown only ; no vibrissze on the mouth-border. No bristle on outer side of tibize. Family Ortalide. Auxiliary vein separated from the first longitudinal and running to border of wing in the usual way under an acute angle and re- maining perfectly distinct in its whole length; third longitudinal vein generally with coarse hairs. ‘Two posterior basal cells large, the outward one frequently prolonged in an acute angle. Front with bristles on the upper part only. No vibrissze at the border of the mouth. Clypeus very much developed. Middle tibiz alone with spurs; no bristle on tibiz. Ovipositor of 9 flattened and horny, composed of three elongated segments and ending in a simple point. Family Z7ypetcde. End of auxiliary veins runs steeply to the border of the wing and becomes obsolete ; first longitudinal vein always with bristles, the third frequently, the fifth sometimes ; the hindermost posterior cell produced to a point. Front on each side with two rows of bristles, one above and placed interiorly, and one below. No vibrissze on border of mouth. Clypeus none or rudimentary. Middle tibize only with spurs; no bristle present on tibize. Ovipositor horny, as in preceding family. Family Loncheide. Auxiliary vein runs to border of the wing in the usual way under an acute angle and without becoming obsolete and near to the first longitudinal vein ; this vein is bare. ‘Two posterior basal cells small. Front at each side with a single row of bristles. No vibrisse. CHARACTERISTICS OF FAMILIES OF DIPTERA. xvii Clypeus rudimentary. Middle tibiz with spurs. Ovipositor con- sists of three joints and is horny and flat. Family Sapromyzide. Auxiliary vein as in the preceding, frequently very much approxi- mated to the first longitudinal vein. Costa without bristles or marginal spine. Posterior basal cells small. No peculiar hairs on the longitudinal veins. Front with a single row of bristles on each side. Only the middle tibiz have terminal spurs; all have the small erect bristles. Ovipositor not horny. Family eteroneuride. First longitudinal vein short, auxiliary very much approximated to it. No bristles on costa. Basal cells small. Front with long bristles. A vibrissa on the border of the mouth at each side. Palpi large. Legs slender. Middle and posterior tarsi with spurs. Family Opomyzide. First longitudinal vein much abbreviated ; the auxiliary becomes obsolete before reaching completely the first longitudinal vein ; the latter sends out before its end, towards the costa, a branch, which may be considered as the end of the auxiliary vein. Basal cells small. Axillary incision and alulz wanting. Front with stout bristles above Border of mouth pubescent and with long hairs. Palpi small. Family Sepside. Auxiliary vein distinctly separated from the first longitudinal veins. Posterior basal cells large. Head rounded. Front bristly. Border of mouth more or less hairy, the foremost hair often imitating a vibrissa. Family Prophilide. Front with some small bristles above only. A vibrissa on each side of the border of the mouth. Abdomen often petiolate and curved. Auxiliary vein coalescent with the first longitudinal vein along its whole length. Family Geomyzide. Front with stout bristles above. Border of the mouth with vibrissee. Bristles along costa. First longitudinal very short, the auxiliary separated from it only near base. Posterior basal cells very small. All the tibize having an erect hair on the outer side before the tip. b xviii SHORT ACCOUNT OF THE MORE IMPORTANT Family Zphydride. Face very convex, covered with hairs and bristles, but no vibrissze. Clypeus large. Proboscis incrassated with a swollen chin. Neura- tion incomplete. Auxiliary vein distinct only at its base. Anterior basal cell united to discal cell. Family Drosothilide. No bristles along costa. First iongitudinal vein very much cur- tailed ; auxiliary rudimentary. Front bristly above. Small vibrissa at border of mouth. A distinct sub-antennal furrow. Antenne with third joint long, terminal bristle pectinate or pubescent. Family Chloropide. No bristles along costa. No auxiliary vein. Anterior small basal cell united to discal, the posterior one wanting. Bristles only on the crown. Border of mouth with no vibrissz, but sometimes a single hair. Family Agromyzide. No costal bristles. First longitudinal vein short, the auxiliary connected with it at tip; posterior transverse vein far distant from the border. Front with strong bristles. Border of mouth with vibrissa on each side. Third joint of antennee rounded, terminal bristle bare or pubescent. Family Phytomyzide. No bristles along costa. Veining much as in above, but no posterior transverse vein. Family Astrade. No bristle along costa. First and second longitudinal vein short. The two posterior basal cells, as well as the transverse vein, wanting. Family Lorboride. Neuration incomplete, only the commencement of the auxiliary vein being seen. Thorax, scutellum, and abdomen flat. Front bristly. Face excavated, with a vibrissa on each side of border of mouth. Family Phoride. Wings with several stout veins running along the costa, and three or four weak ones which run across surface of wings and not com- pletely connected with hindmost of the stout veins from which they seem to issue. Antennze apparently only single-jointed, with long bristle. CHARAECTE RISLPIGES, OF FAMILIES OF DIPTERA, —xix Family AZippoboscide. Body horny and flattened. Head tlattened. Antennze composed of one joint only, and furnished with terminal bristle. First joint of all, or, at least, of the anterior and middle tarsi, abbreviated. Family Braulide. Wingless and blind ; parasitic on hive bee. Family WVycteribide. Antenne short, 2-jointed. Head not flattened. First joint of all the tarsi long, or very long in comparison with the following. Eyes present. Spider-like. ROR AT Ac Page 12, line 28, for ‘* Centis ” vead “ Curtis.” Page 15, insert ‘* Anisomerinz ” in Fam. I1. Page 16, Fam. 31. for ‘‘ Desidze” read “ Dexide.” Page 16, insert ‘‘ Fam. Leptidee”’ after “‘ Tabanide.” Page 23, line 8, also pages 25 and 32, for “ pupiate” vead “ pupate.” Page 31, Sarcopsyllus gallinaceus belongs to a perfectly distinct genus to galline. Page 32, line 12, for ‘‘ Antenne” vead “ Palpi.” Page 35, line 20, for “ Palicide ” vead ‘* Pulicide.” Page 39, fig. 6, for ‘‘Catacha” vead ** Catocha.” Page 78, line 1, for ‘“‘ingulbine” read “ inquiline.” Page 86, line 27, for ‘* Rud” vead ‘‘ Rnd.” Page 93, line 13, for “ States” vead “ Slates.” Page 96, line 13, for “larve ” read “ larva.” Page 172, line 23, and page 173, for ‘‘Grumm” vead “ Grimm ” i a =e > wa eo Cecidomyia, IA. Campylomyza, 6A Lestremia, 7A. Colpodia, 8a. Asynapta, 4A. Catocha, 5A. Lasioptera, I0A. WINGS OF SOME CECIDOMIVIAD. de ASE le FIG 4. BIG: T lds Gp Fie, 8, BIG. 2. FIG. 9. Fic. 1.—Hormomyta fasciata. FG. 2.—Lasioptera rubi. Fic. 3.—Micromyia globifer ; A., enlarged basal joint of antenna. Fic. 4.—Antenna of A. fasczata. Fic. 5.—Antenna of Epidosis gracilis. Fic. 6.—Antenna of Campylomyza halterata. Fic. 7.—Antenna of Dzplosis buxt. Fic. 8.—Antenna of Asphondylia sarothamnt, Fic. 9.—Antenna of Lestremia carnea. Pe Aw lebiia: Fic. 68. EG 7G: os FIG. 58 FIG 4B. PLare IIL. Fic. 1.—Larva of 47bi0 fomone ; A, ventral surface. 1G, 2.—Pupa of 4. pomone. Fic. 3.—Leg of Anarete albipennis. Fic. 4.—Wing (A) and antenna (8) of Scatopse bifilata, Fic. 5.—A, Antenna of Asfistes berolinensis 5 B, wing of ditto ; c, leg of ditto. Fic. 6 —a, Bibio marc’; B, leg of Bibio; Cc, Antenna of B. Marci. Fic. 7.—Aa, Wing of Dilophus febrilis ; B, leg of ditto; c, antenna of ditto. OR. IG. I FIG. 5- Hue JON ——— il NB M\ 1 \ mn f We We FIG, 9. FIG. 10. IG. F hironomideé. G PLATE IV. AN ACCOUNT OF BRITISH- FLIES (DIPTERA). CEE ih Rae: POPS Sica VDI Peale Ans One of the branches of science that has advanced with rapid strides during recent years is geology; in all quarters of the globe fresh discoveries have been made, which have entirely altered many of the old theories and beliefs. We have here only to deal with one branch of geology, namely Paleontology, or the study of fossil animals and plants. At the end of the last century William Smith, a land surveyor, laid the foundation of Palzeontology. He showed that strata could be traced and identified by their included fossil animal remains, and in 1815 he published his work on ‘Strata Identified by their Organic Fossils,” and thus laid the foundation of a new branch of geology that was destined to take the place of mineralogy as the handmaid of geology. From this time onwards continual advances have been made in paleontological study, in all parts of Europe and America. England has been especially to the fore in this respect. It is, however, com- paratively recently that insects have attracted the attention of fossil collectors. We owe our knowledge chiefly to Scudder, Brodie, Heer, Loew, etc. Scudder has published a good account in the American Government Reports. Brodie had, however, previously written on the Mesozoic and Tertiary insects, and had figured a good many specimens, Prior to giving an account of the fossil Diptera it seems well to append a short description of the order. 2 AN ACCOUNT OF BRITISH FLIES. Order DIPTERA. Mouth suctorial, and used for piercing, the labium being greatly developed and forming a gutter for the reception of the lancets (maxillee and mandibles). This proboscis, which is chiefly made up of the labium, ends in a fleshy swollen tongue, and is without palps. It is closed above by the labrum. The maxillz are provided with palps; the mouth, however, may be obsolete or closed. The head is usually large and spherical, and is attached to the thorax by a short neck. ‘Two large facetted eyes are present, and there may be ocelli as well. In the g the eyes may join in the middle line, this being a valuable way to distinguish sex. The antennz are of two forms, («) long and filiform, and composed of many joints ; or (/9) short, with the third joint inflated, and bearing two or three tapering joints or a bristle. The thorax is usually large and compact ; the prothorax very much reduced, and attached as a collar to the mesothorax, which is very large and is developed at the expense of the other two regions of the thorax. One pair of true wings only developed, these being the anterior ones, and are usually transparent and never folded, with an inferior basal lobe. Veins crowded in front, distant behind. Cross veins few. The hind wings reduced to small club-shaped laminze, known as halteres. Both may be absent. The abdomen generally small, but may be elongated, as in the Tipulidee, and composed of five to nine segments. Legs six in number, and slender, having five jointed tarsuses, ending in ungues or “pads” for attachment. The nervous system presents various modifications—in some the ganglia of the thorax and abdomen become fused, or there may be three thoracic ganglia and five or six abdominal ganglia. ‘The male genital organs consist of two testes with vasa deferentia and copulatory appendages. The female have three receptacula seminis in connection with the vagina, and in some cases have a retractile ovipositor. Having given a short general description of the Diptera we can now pass on to the review of the fossil species. In dealing with the ancestral forms of our flies, we include those found in all parts of the world, as very few have been discovered in England, compared FOSSIL DIPTERA. 3 with the number that have been found on the Continent and in America. One of the chief modes of preservation is in amber, the greater number of species having been found in this state. The earliest recorded occurrence of Diptera is in the Mesozoic period, although insects appeared in the early Palsozoic period. The extreme fragility of insects renders their preservation difficult, and we therefore find but a very scanty representation of the Dipterous fauna. It will be only possible here to give a short account of the genera, many of which are described only from such fragmentary remains as wings and other detached portions. a,——- BRACHYCERA, Fam. Dolichopodide.—The members of this family are very abund- ant in the fossil state, being beautifully preserved in amber. Particular attention has been paid to these by Loew, who has enumerated nearly seventy species of Dolichopus, Rhaphium, Potlopus, Medeterus, and Chrysotus. The genus Dolichopus has also been described from Wyoming. Fam. £mpide.—This family has been figured by Brodie from the Wealden of England ; and, according to Giebel, the species described belongs to a new genus—//asmona. Loew has described the genus £77s from the Rhenish coal and sixteen from amber. Giebel, Heer, and Loew have described many other genera besides these from the amber of the Tertiaries. Fam. Bombylide.—Alone found in the Tertiaries, the genus Anthrax being found at Oeningen and on the Rhine. They are mostly found in amber. Fam. Asi/ide.—Brodie describes an Asz/us from the Lower Lias, and Germar another (Asz/icus) from the oolite of Solenhofen. These are the only two recorded Mesozoic species. In amber the Asilidze are more abundant. Many are described from Oeningen and in Sicilian amber. Fam. ZLeptide.—This family is rare in a fossil state. One species has been recognised in the Eocene of the Isle of Wight. Fam. Zabanide.—The Swiss geologist, Heer, describes and figures one of this family from Oeningen, and it is also reported from the Rhenish coal. Fam. Stratiomyide.—Both perfect insects and larvze have been found in the Tertiary and Quaternary deposits. They have mostly come from Aix, where Serres recognised Oxycera and Sargus. TZ, 4 AN ACCOUNT OF BRITISH FLIES. Oustalet also describes a species of Stratiomys from Pontary in the Miocene deposits. (.—NEMATOCERA. Fam. Ahyphide.—Brodie has figured a species of this family from the English Purbecks under the name of ARAiphus priscus. It is more abundant in the Tertiaries, and is described by Heer. Fam. Zipulide.—We now come to a very abundant family, both in present and past times. The Tipulidz attained great variety in the Tertiary period, which contained many that are now entirely extinct. The Tipulidz are recorded in the Oolite of Solenhofen by Weyen- bergh, and from the Lias and Purbecks by Brodie, Westwood and Murchison. I have also found a specimen in the Wealden, although in a very imperfect condition. A great many are also recorded from that great storehouse of insects of Tertiary times—viz., amber. Loew has found as many as sixteen species of Tipulz in amber, one of Jacrochile and four of Dixa, Tipule has also been reported from Aix, Utah, and Italy, and also from Sicilian amber. It has also been recognised in the Eocene of the Isle of Wight and the larval form at Sieblos. Fam. Chironomide.—These delicate little flies have been preserved since Mesozoic times, where they seem to have been of not un- common occurrence. But it is not until we get to the Tertiary ambers that we find them in any abundance. They are recorded from the English Purbecks and from the Lias of Dobbertin. It is also probable that Rhiyphus priscus, described by Brodie, and men- tioned above, belongs to this family, and not to the Rhyphidz. If so, this adds another one to the list of Mesozoic forms of this family. Fam. Culicide. —'Two imperfect specimens from the English Purbecks are referred by Brodie to this family. One to the genus Culex, namely, C. fosszlis, has the antennze and legs well preserved, but the wings are entirely absent. Of course, the amber has preserved many genera and species, especially in Aix and Utah, and in the Tertiaries of the Isle of Wight. Fam. 4biontde.—This family is reported to occur in Mesozoic strata by Geinitz, who figures a species under the name of Protomyia dubia, from the Lias. Scudder, however, says this is not a Dipteron at all. So we must at present only consider this family as a Tertiary one. But in Tertiary times this must have been a very abundant FOSSIL. DIPTERA. 5 family, especially in specimens, but not so in species, for as many as a thousand specimens have been alone found at Florissant, according to Scudder. But amongst these thousand there are only fifteen to twenty species. Bibio is one of the most plentiful genera, and is abundant at Oeningen. They are rare in amber, but abundant in the Tertiary rocks. Fam. Stmudide.—In the Purbecks of England two species of this family have been preserved, namely, Semulium humidum and Simu- lium priscus. Others are also found in the Tertiaries. Fam. JZycetophylide.—This family, again, is found in the Mesozoic period, several genera having been described by Brodie under the names /latyura = Adonia of Giebel, and Macrocera = Sama of Giebel. Another genus, Z/zras, now extinct, has been figured by Westwood. In the Tertiary formations these flies appear abundantly, many of which are now extinct as generic types. They are found both in the amber and Tertiary rocks, the species being generally distinct in the two modes of preservation. For instance, Sciobia, Aclada and fleterotricha are genera peculiar to the amber, not being found in the rocks. A great number of species have been described, and from very wide localities, especially from Aix, Utah, Wyoming, Oeningen, Florissant, and England. Fam. Cecidomytde.—Members of this family have mostly been found in amber, there being no record of them in Mesozoic times. Fam. Syrphide.—It is somewhat doubtful if this family is really represented in time earlier than the Tertiary. ‘Two species have been referred to the Syrphidz from the Mesozoic rocks; one from the renowned rocks of Solenhofen, which, according to Weyen- bergh, is a Chez/osta, another has been figured by Brodie from the Purbeck that may possibly belong here, but being only fragmentary, its true nature remains very doubtful. The following genera are present in the Tertiary beds, viz., Xylota, Chetlosia, Volucella, Rhingia, Syrphus, and Eristalis. The following table, taken from part of Scudder’s table of the Geological distribution of insects in his systematic review of their fossil remains, shows the range and time of origin of the four great divisions of Diptera. 6 AN ACCOUNT OF BRITISH FLIES. | Trias. Lias. Oolite. | Cret. |/Tertiary. || Recent. Diptera: oe Se eee ee ae | | 1. Eproboscidea 2. Cyclorhapha 3. Brachycera 4. Nematocera It is here seen that the first traces of flies are to be met with in the Lias. No doubt future discoveries will place the date of appear- ance at least in the Trias, or possibly even in the later Palzeozoic rocks. At present there is only one hexapod order in the Paleozoic rocks known, namely, the Paleodictyoptera, which became extinct in Triassic times. It may be that from these Palzodictyoptera all the existing orders became differentiated. They die out, as I said before, in the Trias, and are there replaced by Orthoptera and Neuroptera, to which they present close affinities. So far no Diptera, Lepidoptera, Hemiptera or Hymenoptera have been discovered prior to Liassic times. From this fact some weight may be given to the assumption that the existing orders were differentiated in the Triassic period. The Orthoptera and Neuroptera were the most abundant Mesozoic forms, and are now replaced by the more highly developed orders, such as Lepidoptera, Coleoptera, and Diptera. As to the point where the Diptera deviated from the ancestral order, we are at present in the dark; but further researches in the rocks of new localities may in time throw light on this interesting point. In another chapter we will see if the Embryology of the flies throws any light on their phylogeny. GHAPTER: If. CLASSIFICATION OF DIPTERA, WITH AN INTRODUCTORY AC- COUNT OF THE ANCIENT AND MODERN CLASSIFICATION OF INSECTA. THE classification of all animals must necessarily be subject to continual change and re-arrangement, as the discovery of new species » and genera, and the study of known forms, takes place. It is usually a matter of no little interest to compare the ancient and modern methods of arrangement, and as the Diptera, with the rest of the Insecta, have been subject to much alteration in their systematic position, we will here consider the old modes, and also in some degree follow the rise of Entomology. Several hundreds of years B.c., insects had attracted the study of the philosophers, but as all the works were burnt in the libraries, we are comparatively in the dark upon the subject, prior to the time when the great naturalist, Aristotle, wrote. We glean from his writings that much was known before his time of the subject of Entomology. Pliny also tells us that Hippo- crates, in the 8oth Olympiad (5th century B.c.), wrote on insects. To Aristotle we are indebted for the first account of the Diptera; he divided them into two great sections, making the defensive weapon the point of difference. Section I. he called Lmprosthocentra, and II. Opesthocentra,; the former, he said, possessed an oral sting, the latter an anal. A great number of men immediately following Aristotle wrote on insects, both in Greece and Rome, amongst whom we may mention Democritus, Meander of Heraclea, Virgil, Fabianus, Pliny, and M. Varro. Pliny classified insects into three groups: 1. Flying insects, 2. Naked-winged insects, and 3. Protected-winged insects, his eleventh book being entirely devoted to insects. Some few unimportant writers followed, but until we reach the sixteenth century 8 AN ACCOUNT OF BRITISH LILIES. little progress is discernible in this science, unless it be in Arabian. As the old longing for art and science left Greece and Rome, it went to some extent to Arabia, and here we find some considerable ad- vance in the study of insects; amongst those Arabian botanists whose names are known for their valuable knowledge of plants, and who likewise paid no little attention to insects, must be mentioned Rhazes and Avenzoa. The “dark ages” pass on, and what advance the study made then we are unable to say. Not until about 1520 do we find the subject renewed. In 1549 Agricola published his ‘‘ De Animalibus Subterraneis,” and in this we find the earliest systematic arrangement of insects. Agricola in this work divided them into walking, flying, and swimming groups, and he described a good many species. Again, in 1557, another important work was brought out, namely, “De Differentiis Animalium,” in which an account of the insects appeared. About fifty years later the Professor of Medicine at Bologna, Aldrovandus, wrote a large folio volume on insects, “‘ De Animalibus Insectis,” and his work was notable for the illustrations (woodcuts). He was undoubtedly an enthusiastic entomologist ; it is said he kept a painter for thirty years, whose sole employment was delineating his specimens. Aldrovandus classified the insects in two groups : 1. Favica (terrestrial), 2. Non-favica (aquatic), and formed orders according to the arrangement of the wings and feet. Following Aldrovandus came Frenzius, who, in 1612, classed the insects in three great groups, which he named aerea, aquatica, and terrea et reptantia. Some entomologists then seem to have paid attention to certain Diptera. Redi, in 1671, gave a good account of several lice, parasitic upon birds, in his “‘ Experimenta circa Gene- rationem Insectorum,” and soon after Sangallo wrote a paper on the gnat (Culex pipiens), illustrated by a plate. About this period the microscope began to come into use, and many important physiological features in the insects were discovered, notably the circulation of the blood. The use of the microscope made great advances in the study of insects. The use, however, of magnifying power was known before this, for numbers of years. Amongst those who worked at the period on the microscopical investigations of insects were Power, Hooke, and Hartsoeker. Hooke, in 1665, published his ‘“ Micrographia,” a work relating to the microscopical structure of insects. We must now consider that great anatomical entomologist, Swam- CLASSIFICATION OF DIPTERA. 9 merdam, who, after years and years of work, brought out his “ His- toria Insectorum Generalis.” It was first published at Utrecht in 1669. This work was afterwards published in French, Latin, and English. At first the value of this publication was not known, and no one would publish it in England until 1758, and it was then printed with the edition of the “ Biblia Nature.” The scheme of arrangement presented in this work is very different to any preceding author. He classed the insects in four groups: Ist Group or Class: No change of form, but which quit the egg in the same state and appearance they are to retain during life (Spiders, onisci, etc.). 2nd Class: No wings on leaving the egg; other members formed ; after passing out of a nymph state wings appear and the insect can breed (Locusts, dragon-flies). 3rd Class: Animal isin a disguised state before issuing from the egg, and then eats and grows, forming the members of the insect into which it is to be converted under the skin, and which it leaves, and then it is the pupa or chrysalis (Moths, etc.). 4th Class: The pupa retains two skins, one the larval (Ichneumon). In 1688 Blankaart’s ‘‘Schou Berg der Rupsen, Wormer, Maden, etc.,” was published. This Dutch physician in this work gave an account of many larvee, including a dozen fly larve. The plates in this are wonderfully executed for the age. The eighteenth century produced many great entomologists, and at the end we shall see an immense advance in entomological know- ledge. At first came Ray, Lister, and Reaumur. Ray’s great work was “Historia Insectorum,” published in 1810, after his death, by Dr. Derham. ‘This great naturalist divided the insects into two sections : (1) Those that undergo transformation in their form. (2) Those that do not pass through any transformation after being produced in the first instance. He formed his orders according to a number of characters, such as the feet, the habits, odour, larvae, etc. He included the Vermes in his classification of insects. He may have considered these in- cluded Vermes as the larval stages of insects. Between 1734 and 1742 Reaumur published a five-volume work entitled “ Mémoires pour servir 4 l’Histoire des Insectes.” This work contained as many as two hundred plates, and was the best work published so far. There were two editions, one in French and another in Dutch. This work of Reaumur’s put fresh energy into the entomologists of the Continent. Almost at the same time as Reaumur’s writings there commenced to appear papers by the great Swedish naturalist, Linnzeus. In 1735 he published the first edition of his renowned and valuable work, 10 AN ACCOUNT: OF BRIPLSH (POLES. “Systema Nature.” In this edition he classified insects into four classes. The first he called the Coleoptera, the second the Angiop- tera, the third the Hemiptera, and the fourth the Apzera. The Coleoptera, or covered wings, included the beetles. The Angioptera, or naked-winged insects, were the moths and_butter- flies. Aptera, having limbs but no wings, included the spiders, fleas and lobsters, etc., whilst in the Hemiptera he placed such insects as the bugs and locusts. In this first edition we see he includes other orders, namely, Vermes, Mollusca, and Echini; thus somewhat following Reaumur. This we must notice as a curious piece of retrogression, as even Aristotle saw the difference between many of these, and classified the sea-urchins in a different class to the insects. Finally, in the edition of 1767 he classified insects in seven orders instead of four, and at the same time took away the echini, etc., from the class Insecta and placed them in a class called the Vermes. This class, then, is seen to contain a great number of most varied forms. We find here worms, Czlenterates, Polyzoa, Mollusca, Echinoderms, etc., all mixed up together. His seven orders of insects were the following : 1. Coleoptera ; 2. Hemiptera ; 3. Lepidoptera; 4. Neuroptera; 5. Hymen- optera ; 6. Diptera; 7. Aptera. And thus we see our present arrangement of orders is nearly parallel to this. Another arrangement of the insects, of no value, but of some interest, is that published by Dr. Hill in his “ History of Animals.” He divided the class Insecta into three groups, namely : I. Aptera, having no wings. 2. Pteraria, winged. diptera, two-winged flies. tetraptera, four-winged flies. 3. Gymnarthridia, soft bodied, with legs. Then followed a most remarkable system of classification, well known on the Continent as the Scvopoli System. This was brought forward in a work entitled ‘‘Introductio ad Historiam Naturalem,” in 1777. Scropoli followed the arrangement of Linnzus; but his nomenclature was very different, and afterwards alterations were made. He seemed to consider each order should be coupled with the name of the entomologist who has worked at it; and thus we find the following curious arrangement, which met with some success on the Continent (he made five orders) : I. Swammerdamii—lucifuga. 2. Geoffroy—gymnoptera. CLASSIFICATION OF DIPTERA. II 3. Roeselii—lepidoptera. 4. Reaumurii—proboscidea. 5. Frischii—coleoptera. He started by changing the Linnzan names Hemiptera, Hymen- optera, Diptera to Proboscidea, Aculeata, and Halterata respectively. His first order (Lucifuga) included the Crustacea ; the second the Halterata, Aculeata, and Caudata; the third the genus Sphinx, Phalzna, and Papilio. The two last divisions were respectively divided into terrestrial and aquatic. Another author who greatly improved this study was Schaeffer, who in his publications between 1764 and 1777 gave to the world some valuable instruction in the mode of insect-collecting and in the description of the microscopes used. He also described a large number of species to illustrate his system of classification, which differed considerably from the Linnzean method, and which became of some repute. He formed seven orders, the characters of which it is not possible to give here. ‘The following are the seven orders : 1. Insecta coleoptero-macroptera. 2 », coleoptero-microptera. 3. 4, coleoptero-hymenoptera=hemiptera. 4. », hymeno-lepidoptera. os »» | hymeno-gymnoptera. 7 BS diptera, bes aptera. About the latter end of the eighteenth century a good many lists of species had been published, both in England and abroad, and the science of entomology made great strides, but as yet no specialists of any repute had come forward. Entomologists were, in fact, only finding out some systematic base to work upon. As we have already seen, a large number of varied modes of arrangements had been formed, only one of which, the Linnzan, being taken into any account at the present day. A man destined to overthrow the Linnean system for a short time, and whose classification is still considered of great value, appeared at this period, namely, Fabricius, who in 1775 brought forward his novel classification in his work entitled ‘Systema Entomologica.” The mode of classification that he adopted was by the characters of the mouth parts. He continued to publish a large number of systematic works, each one containing a modified arrangement of the preceding, and in his last work the insects were divided into the following thirteen orders: 1. L/ew- therata; 2. Ulonata; 3. Synistata; 4. Piezata; 5. Odonata; 6. Mitosata ; 7. Unogate ; 8. Polygnata ; 9. Kleistagnata ; 10. Exoch- mata; 11. Glossata; 12. Rhyngota; 13. Anttiata. 107) AN ACCOUNT, OF BRITISH, TAIES. Fabricius wrote in both Latin and German. We must not forget to mention before leaving the present century the great work commenced in 1792 by Donovan ; this work, entitled “The Natural History of British Insects,” not being completed until 1809; it was a great advance in our knowledge of insects of our own country. As we get into the nineteenth century we find a great series of advances being made, more especially during the last fifty years. In 1800 many valuable entomological works were published, amongst which we must notice the ‘‘ Fauna Suecica ” and Cuvier’s ‘‘ Anatomie Comparée,” which treats the insects fully. Cuvier also formed a new arrangement on the Fabrician system. He divided insects into two classes: 1. Those with jaws. 2. Those without jaws. Another valuable work appearing in this year is Donovan’s *‘ Insects of India.” In the year 1801 Lamarck moulded another theory of classification, making the mouth parts his centre of observation. He formed three classes, namely: 1. That in which the insects had mandibles and jaws; 2. Those with mandibles and a kind of trunk. 3. Those having a sucking apparatus. He also classified the Coleoptera into three sub-families, according to the joints of the feet. He also removed the Linnzean afzera to a class preceding the Insecta. In the following year we find works appearing more abundantly on special orders, such as Marsham’s “ Coleoptera” and Kirby’s “Apum Angliz.” Henceforth from the period we have now reached, we find countless entomological works, both general and specialistic, by such men as Centis, Westwood, Kirby, Zittel, and hundreds of others. ‘The formation of the Entomological Society in London, in 1838, gave a fresh impetus to the study, and now in all parts of the world we find entomological societies, with their valuable record of observations published in the transactions. We must now pass on to the more important part of this chapter to us, namely, the account of the classification of Diptera. We have seen that Aristotle classed them in two great sections, and the various names under which they have been known, some of which still cling to them at the present day. Very little work is seen to have been done in England in this order, as is seen by the absence of literature, but on the continent the Diptera began to receive much attention in the early part of the nineteenth century. Meigen, in 1820, added greatly to the knowledge of flies by the publication of his great work in six volumes of ‘ European Diptera.” ‘Then followed the descrip- CLASSIFICATION OF DIPTERA. 13 tions of a large number of European and Exotic genera and species, and thus a foundation for a satisfactory classification was arrived at. Latreille was one of the first who attacked this subject in a scientific way, and he worked at the affinities of the group. He based his classification on the trophi and the transformations. Macquart classified the Diptera as follows : Division 1. Memocera=Tipulide and Culicidz. Ae 2. Brachycera. Sub. Div. 1. Hexacheta (six sete in mouth). > ~6=—oy:~SOsi«aX’-«s ’Kracheta (four ditto). y> 53 «ie. D'cheeta. Latreille, in his ‘“‘ Familles Naturelles,” classified them according to their metamorphosis, and divides them into four families, viz.: rt. Nemocera ; 2. Tanystoma ; 3. Notacantha; 4. Athericera. Number three including the S¢tratiomydie. This arrangement of Latreille’s is nearly followed by Westwood in his “ Introduction to the Modern Classification of Insects” (1840). He divides the flies into the following two sections : Section 1.—Head always distinct from thorax. Claws of tarsi not dentated. Larvze develop outside the parent. Section 2—Head immersed in the thorax. Claws denticulate. Larva nourished in the parent. Section 1,—A. NWemocera. (Stirps 1.) Antennz having more than six joints. Palpi four to five jointed = Culicidz Pipulidee. B. Lrachycera. Antenne having not more than three joints. Palpi one to two jointed. (Stirps 2.) Votacantha. Antenne apparently composed of only three joints ; last joint articulated. Proboscis exserted, seldom enclosing more than two lancets. Structure of the mouth very incomplete, and number of setz variable. Pupa coarctate; the skin of the larva nearly retaining its previous form = (Stratiomide, Efe). (Stirps 3.) Zanystoma. Antenne only three-jointed, terminated by a seta. Proboscis exserted generally with four sete. Pupa incomplete = (Zabanide, Bombyliide, LEmpide Leptide, Dolichopodide, etc.). (Stirps 4.) Athericera. Antenne with only two or three joints, terminated 14 AN ACCOUNT OF. BRITISH FLIES. by a seta. Proboscis generally withdrawn into a cavity, with two sete. Pupa coarctate = (Sy phide, Conopide, Muscide), Section 2.—(Stirps 5.) Pupipara= Homaloptera (Leach). Head immersed in the thorax. Claws denticulated. Larve nourished in the mother = (/7ippoboscidea, ete.) Since Westwood’s classification (1840) several alterations have been made. In 1851 Walker’s “ Diptera, Insecta Britannica,” in three volumes, was published. This is the fullest account of British flies that has been published. A great number of species are described in it, many of which seem to be of doubtful repute. In this work, which is, unfortunately, out of print, the following classification is adopted. The Diptera are divided into three groups: 1. Suctoridea ; 2. Pro- boscidea ; 3. Eproboscidea, according to the following characters : Lying flat in cavities at the sides of the head - 1 « Seated in front of Tee | close, side by side - 2 the head. > N distant = - = 3 tenne. An- The second group, or the Proboscidea, is divided into three sections: 1. Wemocera ; 2. Brachycera; and 3. Hypocera (Phoride). It will be seen that this third section is done away with in Verrall’s list, and that the family PZoride is placed in the Proboscidea, just in front of the Eproboscidea. The Aphanipiera, or fleas, are included in the Diptera by Walker, who enumerates fourteen species; while Verrall, in his recent list, only mentions thirteen species in this family. It will be seen that a large number of species mentioned by Walker are cut out by Verrall, as he considers their record doubtful. In Kirby’s ‘‘ Text-book of Entomology ” (1885) the Aphaniptera are also included in the order Diptera. In this book is also men- tioned Westwood’s order, the Achreiopiera, as being possibly included here. ‘They are not, however, British insects, being parasitic on the beaver and somewhat resembling a small cockroach. This author divides the Diptera into four sub-orders, namely : 1. Diptera Aphaniptera. Oe 03 LVemocera. Bly 9s Lrachycera. A es LTomatloptera. The most recent classification is that adopted by Verrall, published in 1888 ;* and it is this classification we intend to use. * “A List of British Diptera.” By H. Verrall, F.E.S., 1888 (Pratt & Co.), This classification was introduced by Brauer. CLASSIFICATION OF DIPTERA. 15 Here the order Diptera is divided into two great sections; one the Orthorrhapha and the other Cyclorrhapha. The Pudicide will be seen to be included in the Mematocera, and several other small differences from former methods of systematic arrangement. I. ORTHORRHAPHA. A. NEMATOCERA. Fam. 1. Pulicide. . Cecidomyiade. . ALycetophilide. Sciarine. Mycetophiline. Sciophilinz. Ceroplatine. Macrocerine. Bolitophiline. Mycetobine. Diadocidine. . Bibtonide. Ny 99 ios) 9 4 5. Smulide. 6. Chironomide. 5 7. Orphnephilide. 8. Culicide. g. Dixide. 0. Ptychopteride. 1. Limnobide. Limnobine. Rhamphidine. Eriopterine. Limnophilinee. Amalopine. Cylindrotomine. Fam. 12. Zipulide. a 3s LAY PHIde. B. BRACHYCERA. Fam. 14. Stratiomyide. Pachygastrinze. Clitellarinze. Stratiomyinee. Sarginee. Berine. 16 AN ACCOUNT, OF BLLIISET SELILES: Fam. 15- 55 Os » 17. AME elles » 19. i 2G: age 2s Fu Oe sn ee: oP) 24. II. CycLoRRHAPHA. Xylophagide. Tabanide. Asilide. Dasypogonine. Laphrine. Asilinee. Bomlylide. Therevide. Scenopinide. Cyrtide. Lmpide. Hybotinee. Empine. Ocydromine. Tachydromine. Dolichopodide. Lonchopteride. C. PROBOSCIDEA. Fam. 25. ICH an ue se » 29 9 ~=30 Fam. 31. » 32. Siete) » 34. Fam. 35. Platypeside. Pipunculide. Syrphide. Conopide. Conopine. Myopine. . stride. . Lachinide. Phasine. Gymnosomine. Phanine. Ocypterine. Tachinine. Deside. Sarcophagine. . Muscide. Anthomyida, Mydeeine. Anthomyine. Homalomyine. Coenosine. Cordyluride. CLASSIFICATION OF DIPTERA. Fam. 36. Phycodromide. » 37. Helomyzide. » 38. Sciomyzide. 52 SO: Lswide: » 40. ALicropeside. » 41. Ortalide. Ortaline. Platystomine. Ulidine. » 42. Trypetide. Dacine. Trypetine. » 43. Loncherde. » 44. Sapromyzide. » 45. LHeteroneuride. » 46. Opomyside. » 47. Sepside. » 48. Piophilide. » 49. Geomyzide. » 50. Lphydride. Notiphilinz Hydrelline. Ephydrine. » 51. Drosophilide. » 52. Chloropide. » 53. Agromyzide. » 54. Phytomyzde. 3 55s Asta: » 56. Borboride. Se ia. Lona: D. EPROBOSCIDEA. Fam. 58. ippoboscide. » 59. Braulide. » 60 Wycteribide. Fam. Psychodide ought to be inserted between Fam. 7 and 8. Fam. Adilichide is given in the list of reputed British species. Another list of Diptera was published by Walker in 1874, but this includes Diptera of all parts of the globe. list nearly half a century ago. only lists of Diptera in English of any importance.* Morris also published a As far as I can find out these are the * B. Cooke has also published a catalogue of the Diptera of Lancashire and Cheshire. Proc. Ent. Soc. Lanc. Ches., 1881. as in the Fauna and Flora of Hastings, etc. Also numerous other local lists, 18 AN ACCOUNT OF BRITISH FLIES. In the Orthorrhapha the pupz escape by a T-shaped rent in the larval skin. The larva has in this division a more or less perfectly developed chitinous head. In the Cyclorrhapha the pupz escape from the larval skin by a circular opening, and the larva has no chitinous first segment, but is quite acephalous. Quite recently (1891)* Osten-Sacken has adopted a new method of classifying the first of Brauer’s sections of the Diptera; namely, the Orthorrhapha, as he considers the attempts made by Schiner and Brauer at dividing this sub-division of the Diptera into smaller groups as unsatisfactory. The latter authors based their groups on characters of subordinate value, taken from the wings and larve, “‘ without sufficient regard for the organization and affinities of the imagos.” Osten-Sacken considers that the study of the organs necessary for the functions of external life will lead to a natural arrangement, such as the eyes and antennez, wings and legs. He divides the (Vemocera into two: (1.) the Zrue Memocera, in- cluding the Cecidomyide, Mycetophilide, Culicide, Chironomide, Tipulide, Psychodide, and possibly the Déxide, may form another family in this group. The remaining families he calls (ii.) Wemocera anomata, these being archaic forms, and having a peculiar geogra- phical distribution.t They also have a different siructure to the True Nemocera. The following are the chief characteristics of the Zrue Wemocera : i, Head never holoptic, and thus the difference in size between the male and female head and the difference in the size of the eyes is very small or absent. il. The eyes are round, oval, or lunate. They may meet, but never in such a way as seen in the holoptic head of the LVemocera anomala. ili. Antenne very large in proportion to the small head. iv. Legs very often long, generally thin and weak, and not fitted for walking, as seen in the Z7pulide. v. Generally more slender and lighter than the Nemocera ano- mala (compare Z7su/a and #zb70) in general appearance. vi. Geographical distribution world-wide ; most inhabiting damp and shady places, and prefer the latter part of the day for flight. * Vide Ent. Mo. Mag., Feb., 1891. + The Bibzonide, for instance, were at their maximum in tertiary times. Giard has given an account of this family in his ‘* Note sur les Bibionides Fossiles.” Bull. Sc. Dép. Nord., tome i., 1878. CLASSIFICATION OF DIPTERA. 19 The WVemocera anomala are characterized by the following distinc- tive features : i. Head holoptic, both in the male and female, but chiefly in the former. In #zéz0, for instance, the ? has non-holoptic eyes. ii. Eyes often bisected, the upper facets being the larger. These two halves may be separated by a smooth, unfacetted stripe, asin the ¢ SLzdio. iii. Legs well adapted for walking, and often, as in Azdio and Stmulium, thick. iv. Male and female generally differ very much. v. Peculiar, often sporadic geographical distribution. Upon these characters Osten-Sacken has founded the two divisions of the Nemocera. Both from these characters, their curious distri- bution, and their archaic nature, we see that this division is quite a natural one, and is founded on more scientific principles than most entomological classifications. Amongst the Orthorrapha Lrachycera he classifies the following families into one group: the Zadvanide, Stratiomyide, Acanthomeride, Leptide (plus Xylophagide). For a long time these families have been converging towards one another, and at last have been united under the name (given by him) Z7emo- cheta. This seems a natural group, and is founded on a chetotactic character ; namely, the total absence of Macrocheete. Besides the bristleless nature of these forms, they are separated from the JVemocera and remaining Brachycera by the following characters, given by Osten-Sacken : 1. The eyes in the male are predominantly holoptic. There are, however, a few exceptions to this rule given by him; viz., Xylophagus, some Australian CAiromyze, Hermetta, etc. But Cenomyza, a close relation to Xylophagus, has holoptic eyes. 2. The variegated colour of the eyes, especially seen in S¢ra¢zo- myide and Tabanide. 3. The extreme variability of the antenne, on the one hand related closely to the Wemocera, and on the other to the Cyclorrhapha. 4. Three well-developed pulvilli are generally present. Legs smooth, and having no bristles, as seen in the Aside, Bombylide, ete. The following, then, are the families recently grouped by Osten- Sacken : FY 20 AN ACCOUNT OF BRITISH FLIES. i. LVemocera. il. LVemocera anomala. Cecidomyide. Bibionidee. Mycetophilidee. Simulidee. Culicidze. Blepharoceride. Chironomide. Rhyphide. Psychodidee. Orphnephilide. Tipulide. Dixidze (?). ill. Eremocheta. Stratiomyide. Tabanide. Acanthomeridee. Leptidze (plus Xylophagidee). The family Xy/ophagide must be given up and united to the Leptide. As we receive more material from the tropics and foreign parts we shall continually find it necessary to alter the classification. The old classification has been adopted to suit European forms; but as the numerous anomalous forms from Chili and North America have shown that the present classification will not hold good, we may expect still further changes when new material is brought from Australia, Africa, and other places, where the Dipterous fauna is scarcely known. It is by the study of exotic forms that we shall eventually arrive at a satisfactory classification, and only by this means. In a letter we received from Mr. Coryndon Mathews we are told as follows: ‘Only a month or two ago Major Yerbury sent me a box of flies from Trincomali, Ceylon, for identification, and amongst some fourteen or fifteen Asz/d@, there was material enough to upset three of Schiner’s and Rondan1’s genera.” The immense importance of the study of foreign species in regard to the classification of flies is thus emphasised; and until we are well acquainted with the Dipterous fauna of all parts of the globe we shall still be in the same changeable and unsatisfactory state in regard to their systematic arrangement. For the present we cannot do better than follow Brauer’s arrange- ment, especially as it has been adopted in the only list of British species. CHAP HR WE Te APHANIPTERA. (NOW INCLUDED IN NEMATOCERA.) Tue Aphaniptera are also known under the following names : Suctoria, De Geer. Siphonaptera, Lat. Aptera, Lam. The following may be taken as the characters of the section or sub-order and thus of the family PULICIDA: Parasitic, with scale-like rudimentary wings, the metathoracic scales being the largest. Tarsus five-jointed; antennz small; mouth formed for suction, composed of mandibles and lingua, long ; maxillze small, in form of triangular scales with four-jointed palpi ; labium minute, three-jointed ; palpi four-jointed. There are four genera: 1. Pulex; 2. Sarcopsylla (the latter not being British) ; 3. Aystrichopsylla, and 4. Typhlopsylla. The history and changes of the “fleas” have been known since the days of Aristotle. He noticed their distinct sex, and that they produced oxwAns dosides. He did not trace the changes of this insect far enough, and thus fancied this progeny was swz generis. He also thought that the adults were generated in the earth spontaneously. This spontaneous generation has been held up by many naturalists since his time, and has been applied to many of the invertebrate animals. I have even, in this nineteenth century, heard people talking of the spontaneous generation of “green fly” and locusts ; but happily this absurd notion is only lingering on amongst very few people. Few animals have had so many theories applied to their origin as the common flea; Scaliger thought they were produced from humours amongst the hairs of dogs. By degrees their true history became known, and to De Geer we are indebted for one of the first good accounts of their transformations. ‘They have attracted attention in all parts of the world. They were formerly thought to 22 AN ACCOUNT OF BRITISH FLIES. live only upon vertebrate blood, but recent discoveries show this to be a fallacy. They are found in large colonies in dry sandy places, where they could not attack vertebrate animals. To make up for this they make for caterpillars and other invertebrata, and suck their juices. There are a good many species, each animal seeming to have a particular one to itself. They may attain a great size, such as Pulex gigas, from America; but our species never attain any great dimensions. By far the greater number belong to the genus Pu/ex, but one that has attracted considerable interest forms another genus, Sarcopsylla. This genus contains the curious and obnoxious “ Jigger ” of South America and Africa, so well described by Waterton in his “ Wanderings.” Although this is not a British insect, a short description is appended, as its history is so extremely interesting. Metamorphosis of the Flea (Pulex). Each female lays about a dozen eggs at a time. The eggs are oblong, or spindle-shaped, and generally whitish in colour. They may be, however, brown in some species. ‘The ova are deposited in Fic. 1.—Larva of P. fe/’s (enlarged).—a, antennz ; P, pointe frontale. various places, such as the cracks in boards, amongst dust, on the hairs of rugs and dogs, and various other places, according to the species. After a time these eggs hatch, and from them come worm-like maggots, very active. The larva is composed of thirteen segments, and is quite apodous (Fig. 1). The last segment may have two strong, curved hooks; the head is sub-ovate and corneous. Antenne and oral appendages are present ; also a pair of eyes. Although these worm-like larvz are active, they never move far, and their mode of nutrition has been disputed and discussed a great deal. It seems true that the female, or mother, after having gorged itself upon the blood of its victim, makes off to its larvae, and there disgorges some of its feast. This congealed blood is often found by the larve, and upon it they feed. It is also said that they gain nourishment from the fleshy part of feathers, etc., which may happen to be close to them. APHANIPTERA. 23 Between the twelfth and fourteenth days the larvze may spin them- selves a small silken cocoon, which lies in and is covered by the dust. Not all spin this silken cocoon ; some pupiate into naked, immobile nymphs, which gradually assume a darker colour, and approach the appearance of the imago. About the seventeenth day of pupal life the imago emerges, and very soon commences its rapid hopping movements and voracious habits. All the larvze do not pupiate at the same time. Some live through the winter and hatch in the spring. Fic. 2.—-Pupa of Pulex irritans (greatly enlarged). Classification. Verrall, in his list of British Diptera, 1888, includes the “fleas” in the Nematocera, and thus does away with the old sub-order, Aphaniptera. The family Pwlicid@ is divided into three genera, and numbers thirteen species in all, viz. : Fam. Pulicide. Genus 1. Pulex, L. Irritans, L. Fasciatus, Bosc. Gallinze, Bouché. Melis, WIk. Sciurorum, Bouché. Canis, Duges. Erinacei, Bouché. Goniocephalus, Tasch. Genus 2. ystrichopsylla, Tasch. Obtusiceps, Rits. Genus 3. Zyphlopsylla, Tasch Octactenus, Kolen. Hexactenus, Kolen. Musculi, Duges. Gracilis, Tasch. 24 AN ACCOUNT OF BRITISH FLIES, Genus 1.—PULEX. Characters of the Genus.—Body oval and compressed, and covered by a hard, chitinous integument, which is covered by hairs and bristles on the back and legs. There are thirteen segments, and they are continuous, there being no distinction into thorax and abdomen. Head small. Mouth suctorial. Upper lip obsolete (unless the lingua represents it), The mandibles are in the form of two flat sete, with a central rib and serrated edges. The lingua is the same length as the mandibles, the three forming a piercing, or puncturing Fic. 3.—Imago of Pulex ?.—a, antenne ; m/, maxillary palpi ; 2, 22, 277, pro-, meso-, and meta-thorax. organ. When at rest these organs are closed by the labial palpi, which form a tubular Zauste/lum. These arise from a small labium, which comes from a very small mentum. The maxillz are sub-triangular appendages, and are coriaceous and are situated at the side of the mouth. They have large maxillary palpi arising from the base, composed of four joints, and formerly mistaken for antenne. Eyes small (=simple ocelli) and round. Antenne are placed in pits behind the eyes. These pits are covered by movable valves. At times the antennz may be withdrawn out of these cavities. They are four-jointed appendages, the third joint being small and cup-shaped. The terminal joint is often transversely striated.* They vary in different species. The thorax is composed of three typical segments, but more distinctly marked than in other insects. On the second, or meso- thoracic, is the first pair of scales, or rudimentary wings, and on the metathoracic segment we find the large scales representing the hind * These striations are really joints. APHANIPTERA. 25 wing (haltere) of the Diptera. This is a point worth noticing, that in these Diptera the posterior rudiment is more developed than the anterior, contrary to the usual arrangement of the wings in flies. Legs, long and strong; the posterior pair formed for leaping. Coxe large. At the four hind legs the coxz articulate to the epimerze by means of a supplemental joint, which is absent in the fore leg. The trochanter is small. Strong femora and setose tibize ending in five-jointed tarsuses. The terminating tarsal joint bears a pair of ungues, or claws. Sarcopsylla penetrans (= Pulex penetrans). This species forms another genus in the Pulicide. It is an insect that has attracted a large amount of attention owing to its unpleasant habits. The male is a small and insignificant insect, which does not seem to be parasitic—at least, as far as we can make out from various accounts. They are usually found in damp and swampy places, and breed in great numbers, the ground swarming with them. The female is the insect that has attracted so much notice. They are known as ‘“‘jiggers,” or the “jighoe,” and inhabit South America, the West Indies, and the West Coast of Africa, etc. ‘The females attach themselves to the feet of travellers and to animals. ‘They chiefly fasten on to the spaces between the toes and under the nails. As soon as they are attached to the skin they burrow into the flesh, and there excavate a nest and attain a great size, often as large as a pea. It is the abdomen only of the female that enlarges. ‘This enlargement is due to the development of the ova in the body. Unless the “jigger” is extracted before this bursts a very nasty wound is produced, leading to ulcerations, and maybe, the destruc- tion of the bone, and amputation is rendered necessary. Wood, in his ‘‘ Insects Abroad,” scouts this idea; but I am assured that if left to themselves they may produce the most serious wounds and disease. They are, however, easily extracted if paid attention to at once. It seems that the ulceration is set up by the larve that are hatched, and escape from the female. The larvee live for a certain time in the host, and then are said to pass out and pupiate in the ground. The female is thus seen to be impregnated before she attacks the host, otherwise no effect is produced. When their bodies are fully swollen they very much remind one of the Brazilian honey-ants, which have their abdomen enormously distended by honey. As such swarms of these “‘jiggers” are seen in certain localities, 26 AN ACCOUNT OF BRITISH FLIES. it seems improbable that they can all find human hosts, or even sufficient vertebrates of any kind. It is said that the species that is found in the dog is different to the one found in man. Whether the species in Africa is different to that in America I do not know. This was the insect that Waterton found so troublesome during his “ Wanderings.” Anatomy of the Larva of Pulex. In all the species there is a slight difference in the form of the larvee, but the general arrangement is the same. The type we take is Fic. 4.—Head of Larva of P. fel’s.—is, upper lip; a, antennz ; #7, maxille ; mb, mandibles ; £2, pharynx; A, maxillee, and B, mandibles, greatly enlarged. the larva of P. felis, parasitic on the cat. This subject has been fully worked out by Laboulbéne and Kunckel, and their researches published in the “ Annals of the Entomological Society of France” (2 and 3). The larva, which may attain the length of a quarter of an inch, is usually of a whitish colour, and in some cases so trans- parent as to: allow the alimentary canal to be examined through the integuments (Fig. 1). The number of body-segments is thirteen, and each is armed by a few setaceous hairs. The last segment is armed also by two strong recurved claws. The head is corneous, and presents certain peculiarities. The antennz are a fair size; their structure can be seen from the figure (4). There is also developed a pair of maxille, with serrated edges, and also a pair of mandibles. The large upper APHANIPTERA, 27 lip has four setaceous hairs upon its under surface. On the dorsal surface of the head we must be careful to note the curious structure known as the “pointe frontale,” so well described in Kunckel’s paper. It is present in the young larvee, and may be seen prior to its exit from the egg. It is a yellowish-brown, horny plate, and seems to vary in shape in the different species of fleas. This appears to have been first noticed by De Geer.* This little corneous plate is placed in a slight depression of the head, and ends in front in a sharp point: the figure will, however, explain best its general shape and appearance in the species of Pulex; namely, P. feds (vide Fig. 1). It must be noticed that this structure is only found in the young larve. It is possibly an organ used to rupture the egg membranes, and thus release the larva. It is no doubt the homologue of the “dorsal plate” found in other insects, so fully described by Kowalevsky,+ and again by Dohrn,{ who says it is formed from a thickening of the serous membrane which covers the dorsal surface; this differs, however, from our “ pointe frontale” by becoming formed into a canal and then into a tube. This frontal plate, seen in embryo fleas and in Pentatomes, in the Phryganide, and as the so-called “ dorsal plate” of “ydrophilus, etc., is also, according to Kunckel, homo- logous to a piece which, if it is developed, exists in the front of the larvee of Crustacea, the Zoza of Cancer menas and Pagures and Porcellanes, of young lobsters, etc. M. Balbiani also notices a curious point in the frontal region of young Phalangide,§ which he regards as the analogue of the appendages found on the dorsal surface in other Arthropods. We may also note the antennz situated on the dorsal surface of the head. They are composed of three joints: the first being rounded, and bearing a few protuberances ; the second is cylindrical, and ends in tentacular-like processes ; from this proceeds the third joint, which is small and pointed. The Alimentary Canal.—This is easily seen in living larvze, owing to their transparency. Two small elongated salivary glands open into the pharynx, which is followed by a short and swollen esophagus, which gradually narrows as it passes into the chylific ventricle, this part of the digestive track is large and elongated, its posterior end is * De Geer, ‘‘ Mémoires pour servir 4 l’Histoire des Insectes,” 1778. + ** Embryologische Studien an Wiirmern u. Arthropoden,” Mém. Ac. Imp., Petersbourg, S. vii., vol. xvi., 1871. + “ Notizen zur Kenntniss d. Insectenentwickelung.”’ Zeitschrift f. wiss. Zool., 1876, § ‘‘Mémoire sur le Développement des Phalangides.” Ann. Scien. Nat., vol. Xvi, 1872. 28 AN ACCOUNT OF BRITISH FLIES. corrugated ; from this end arises the smad// intestine, which has a double flexure. The /arge intestine is swollen, and its walls are very much folded ; it passes into a narrow vectum. At the base of the chylific ventricle open four Ala/pighian tubules, each being long and coiled. The Respiratory System consists of two rows of lateral trachea, united to one another by a tracheal tube in each segment. Nine of these connecting tubules send off a tube to the stigmata, and other tubes ramify in other parts of the body. Nervous System.—We were unable to make out the nervous system of the larvae examined, so append Kunckel’s description verbatim : Fic. 5.—Alimentary Canal of Larva.—a, salivary gland ; 4, cesophagus ; ¢, chy- lific ventricle ; d, small intestine; ¢, large intestine ; 7, rectum; g, Malphigian tubules. “Le systéme nerveux, composé de ganglion arrondis, reliés par de connectifs, et au nombre d’une paire environ par segment, n’a pas été assez soigneusement étudié pour que je puisse le décrire. Il en est de méme du systéme circulatoire.” The natural position of the fleas has caused much discussion. Lamarck considered them Diptera on account of their transformation. Duges considered them nearly related to the Hymenoptera; others to the Hemiptera, on account of the rostral shield. Latreille placed the flea between the Hemiptera and Diptera, as did also Westwood, raising them to an order called Aphaniptera (of Kirby). They are now considered true Diptera, and according to Osten-Sacken are a degraded genus of the family to which belong the small AZycetophile, that live in mushrooms during their larval state. Their metamorphoses certainly agree in many points. The APHANIPIERA. 29 fleas are, however, generally classified at the present day as the first sub-order of the Diptera, namely, the Diptera Aphaniptera, being thus placed between the Hemiptera Anoplura, or lice, and the Diptera Nemocera. Verrall, in his list of British Diptera (1888), places them in the Nemocera. Pulex irritans, L. (the Common Flea). This is the best-known of all the Pu/icide, and has been described over and over again. The following entomologists have given the best descriptions : Leach, Duges, Bouché, Rosel, De Geer, Latreille, Newman, Kirby, and Westwood, and the works of these authors may be consulted for more detailed accounts. The abdomen large, inflated, reddish-brown, with two apical diverging bristles. Bristles developed on each segment, especially on the dorsal surface and around the genitalia. Head short and shining, minutely punctate. Antennz usually carried in the recep- tacles; basal part of maxilla thickened ; palpi composed of four nearly equal joints. Mandible thickened and horny on one side, with small denticles ; thin and hyaline on the other, with numerous deep denticulations. Legs paler than the body. Coxe broad and flat, with a few scattered bristles on the upper surface. Femora also broad and flat, hairy ; a fringe of bristles on the inner side of the hind pair. Thick apical spines on the tibize and tarsi. Ungues fringed on the under surface by little spines (?). The first tarsal joints in the hind legs are the largest ; the fifth joints next in size; the second, third, and fourth in decreasing succession. The two fore legs are differently constructed, two and five being the largest joints ; the first, third and fourth being nearly equal. The last tarsal joint always armed on the under surface by a few spines—generally four in the common flea. _ The Pygidium is composed of disc-like areolz, around which is a ring of rectangular rays. The male is armed with two stylets for copulation. The mode of copulation may easily be seen, by keeping a number of fleas in a glass test-tube. The coupling takes place tail to tail, the female (which is much larger than the male) stands over the male. The pairing sometimes only lasts a few seconds, but usually much longer. Leewenhoeck first discovered the spermatozoa of the flea. He described them as “serpent-like animalcules.” The flea may easily be dissected in water under the microscope, and the alimentary canal, testis, ovary, etc., easily seen. They are best mounted in balsam, after being well soaked in 30 AN ACCOUNT OF BRITISH FLIES. liquor potasse, then washed and soaked again in ¢urpentine and oil of cloves. Length of P. zvritans, about 1 lin. This is one of the commonest fleas, and is parasitic on the human race, especially in Europe, where it extends from the Arctic regions to the warmest parts of the Continent. The /arv@ are pearly white and very active ; several hairs on each segment ; head slightly chitinous and brown ; two short, one-jointed antenne. The last segment armed by two recurved brownish spines. They may be found in the dust, etc., in the crevices of boards. The pupz are enclosed in a silken cocoon and are also found in dust. The larve may also inhabit the human subject, and are said to feed upon the scurf of the hair. Innumerable accounts of the Herculean strength of the common flea have been written by English, French, and German authors, so it is unnecessary to add more to this subject here. Perhaps the account given by Walckenaer, in his “ Histoire Naturelle des In- sectes,” Apttres,* where he describes the military exercises gone through by thirty fleas, is one of the best. The enormous strength and power of leaping displayed by these somewhat obnoxious insects can be comprehended when we consider that if a lion had the same proportion of strength to the size of its body it could leap two-thirds of a mile! Pulex canis, Duges (=P. serraticeps, Gerv.). The ‘“‘ Hundefloh” of the Germans. Resembles P. zrvritans, but is smaller (4 lin.) and paler in colour. Coxce bristly ; femora devoid of bristles and hair. ‘Tibiee thick. The legs generally shorter than in zrritans. The fifth and second tarsi the longest in the two front legs; the first and fifth, in the hind leg, as in zrétans. The fifth being the longest in the front legs in this species; not the second, as in the common flea. The ungues are large and broad, dark in colour, and fringed with black spines on both sides. Last tarsal joint armed with five spines on the under surface. Head small, compressed, ciliated with bristles ; punctate behind. Eyes small and lateral. Mandibles long and slender, transparent, central rib well marked. ‘Tongue same length as the mandibles. Maxillary palp, robust pilose, second joint from base the largest. Mentum small. There is a comb-like fringe on * Vol. iii., p. 366, note. APHANIPTERA. 31 the pro-thorax. Mr. Haliday first discovered the antenne of this species. They are two-jointed, short and flat, the first joint having a bristle near its internal apex, and the other crowned with spines. This species is common on the dog and fox, and most other members of the Cazzde. Pulex galling, Bouché. Deep black above, testaceous below. Differs from zrrifans in being smaller, more compact, and in the length of the antenne, which are lanceolate, the last joint being thin. Maxillary palpi slender and filiform. Femora bare ; tibiz and tarsi spinose. There is a curious comb-like fringe to the pro-thorax. This species is common on the domestic fowl, and especially in the nests. Hundreds may be got by putting the hand in the nest. It is also found on other birds, as the thrush, robin, and in the nests of the blackbird. Mr. Dale believes a species described by West- wood from Ceylon as Sarcopsyllus galltnaceus, to be identical with the one just described.* The larve of Galline are darker than those of the domestic flea, and are found in birds’ nests. LP. galline is also recorded from the nests of the house-martin and from those of the sand-martin, in the cracks in the clay. ‘Those from the nest of the sand-martin were darker than those from the house-martin, and they may be a distinct species.” t We have found P. Airundinis in the nests of the house-martin, but never Gadling, although repeated searches have been made. /P. hirundints does not seem to be given by Verrall; it nevertheless seems to be a perfectly distinct species. May not the Gadiine, recorded above, be the same? Pulex hirundinis, Sam, Curtis, and Walker. Differs from Gadline by being testaceous, and by not being so elongated and having shorter antennz. There is also a black band on the hinder part of the thorax. Abdomen and legs setose. Antennze four-jointed ; the basal joint, having three or four long bristles attached to it, can be entirely withdrawn into the pits. Eyes small and lateral. Maxillary palpi slender, the top segments having a few hairs. Labial palpi setose at the tips. Joints of tarsus gradually decreasing from the first to fourth, the fifth being larger than the fourth, and with more bristles on each side. This species may include P. columbe and Lringille of Walker, * Ent. Mo. Mag., vol. xxvi., p. 161. + Lbid., vol. xxvii., p. 51. Be AN ACCOUNT OF BRITISH FLIES. but, according to his descriptions, they are different. Those that we have examined from the pigeon seem to be slightly different from Hirundinis, being longer and darker and slightly different in the construction of the mouth parts.* P. hirundinis infests swallows, pigeons, sparrows, and other small birds, especially in their nests. The mouth parts have been figured by Curtis as long ago as 1836.t Pulex scturorum, Bouché. Larger than the common flea, and more elongated and paler in colour. Length, 14 to 14 lin. Head bare; body smooth and shining. Antenne short and light in colour, yellowish. Pro-thorax dark and ribbed ; meso-thorax also bare. Legs devoid of hair and bristles as seen in most fleas. First and fifth joints of fore tarsi longest ; the fourth the shortest. In the hind tarsi the first, second, and third, in succession, the fifth being larger than the fourth. Ungues straight and closely fitted together, resembling one claw. This species seems to be exclusively parasitic on the common European squirrel (Sccurus vulgaris), and is met with all over Europe. Pulex melis, Mk. This is a large species, long and hairy. General hue, testaceous. Antenne filiform, long, composed of four joints; the fourth joint longer than the third; the third smaller than the second ; the second longer than the first. Legs setose. Abdomen hairy ; four bristles near the tip. Joints of tarsus decrease in length from the first to the fourth. Length, 14 to 2 lin. This species is parasitic on the badger (AZe/es caxus), and is found all over Europe. Pulex ertnacet, Bouché. A large species infesting the hedgehog, with a curious fringe of small spines on the hind border of the meso-thorax, appearing like black ribs on the meta-thorax (?) We have not seen this species ourselves. Pulex goniocephalus, ‘Tasch. The “ Kaninchenfloh ” of the Germans. Described in Taschen- burg’s “Insectenkunde.” Infesting the weasel, marten, and rabbit. * Described in Walckenaer, ‘‘ Aptéres,” vol. iii, p. 375, pl. 48, fig. 7, and in Walker. + Curtis’s “ British Entomology,” vol. vii., pl. 417. APHANIPTERA. 33 This flea is described by Taschenberg as being short and thick, and yellowish-brown, easily recognisable by the blunt edge with which the vertex passes into the forehead (“leicht kenntlich an der stumpfen Kante, mit welcher der Scheitel in die Stirn tbergeht”). On the under edge of the head stand out from the front to the antennal sockets, on each side, five to six black, blunt spines, and the pronotum also bears the same number on its posterior edge. The abdominal rings have each one row of hairs in their centres. The eye is equally distant from the top and bottom edge of the head ; some bristles are observable in front and behind it. In the anterior legs the four first joints are equally short and thick, the fifth somewhat exceeds the third in length (? ‘das fiinfte etwa von der, Lange der drei voranf- gehenden”). In the middle pair, joints three and four like each other, short and thick, the first a little longer, second and fifth more slender, and second a little shorter than fifth ; in posterior pair joints three and four are short and resemble each other, and together are as long as joint two or five, each of which is a third as long again as the first joint. Body length 2 mm.* It is found also on hares. The same as P. leporis. Pulex fasciatus, Bosc. This resembles Sctuvorum, but is longer and paler. The pro-thoracic comb has eighteen teeth. No black spines on the head. Found on the rat. Genus 2.—HYSTRICHOPSYLLA, Tasch. Head truncate in front; eyes wanting. Cheeks and clypeus densely spinose, and also some of the abdominal segments. The whole body furnished with extremely numerous bristles and hairs. Pulex talpe, Bouché. LT, obtusiceps, Ritsema= < Pulex fasciatus, Lat. (?) Ceratophyllus talpa, Curtis. General colour ferruginous and shiny; head also shiny; the clypeus covered by dark bristles, which hang down and cover the mouth. ‘Thorax small and cylindrical; pro-thorax dark at the sides. Eyes pale, ovate. Antennz ten-jointed; basal joint ovate; the remaining joints composed of rings, bristles on one side; on both sides of the basal joint. Maxillary palpi four-jointed, the basal joint longest. Abdomen compressed, each segment being furnished with dark bristles on the posterior margin. In the female the last segment is elongated on each side, forming two discs. The apex is marked by a number of bristles of large size. * “Tnsecten-Kunde,” vol. v., p. 132. 34 AN ACCOUNT OF BRITISH FLIES. Legs ferruginous, somewhat darker than body. Coxe notched near the posterior joint, on the four hind legs; smaller and not notched on the fore legs. Femora short and thick on four posterior legs, thin on fore legs, all having a few bristles, ‘Tibize and tarsi with strong bristles, especially on the former on the posterior margin. Metatarsi long and thick, first and fifth tarsal joints being the longest. Length, about 1 lin. This is recorded by Curtis and by Walker as infesting the mole. Dale says: ‘‘It is quite certain that Za/pe@ is a misnomer, as it is not found on the mole.”* He found this species in a field-mouse’s nest. Curtis also mentions one similar to his Za/p@ being given him, found on arat. This species has been figured by Curtis. + Genus 3.—TYPHLOPSYLLA, Tasch. Body elongated and narrow. Head in many (specimens) very long; eyes wanting or rudimentary. On the under side of the head are found constantly chitinous bristles, the same on the pronotum, and in a number of species also on several abdominal segments (Tasch., “Wie lohe,” ps:36). T. octactenus, Kolenati= Ceratophyllus elongatus, Curtis. Ochreous, ferruginous, and brown in places; shining, elongated, and attenuated towards the head, which is bare. ‘The antennz are eight-jointed, pilose, sub-clavate ; the first and second joints being large ; the third joint is narrow; the remaining five form an ovate club. Maxillee black; black bristles on the thorax and abdomen. Eight combs along the back. Abdomen attenuated in front, dilated at the apex; genital valves largely developed. Legs pale yellowish ; tibice and tarsi sparingly clothed with long dark hair; claws black. This is the description given by Curtis of C. elongatus, which is parasitic on the yellow bat (V. zoctuda). TL. musculi, Duges = T. murts, Curtis. Dark yellowish-brown. Head covered by short dark hairs, with a few almost black bristles in parts. Body attenuated in front. Comb only on posterior margin of pronotum. Legs having very few hairs or bristles; femora bare and curved ; tibize with black bristles ; fore coxee punctate, with black bristles. Four genal spines. This species infests AZus musculus, Agrarius, Decumanus, rattus, and Arvicola arvalts. * Ent. Mo. Mag., vol. xxvi., p. 161. 7 Curtis’s “ British Entomology,” plate 114. ——— APHANIPTERA. 35 T. asstmilis, Tasch. With only three genal spines. Infests Sorex vulgaris, Mus sylvaticus, Arvicola riparta, and Talpa vulgaris. This species is recorded by Saunders,* but is not mentioned in Verrall’s list. T. gracilis, Tasch. Body elongated, very slender, and light brown. Head above rectilinear ; three spines not on the cheek, but on the suture dividing the antennary cavity from the front of the head. The spines are straight and directed backwards ; the lowest is the shortest, conical, and blunted ; the second longer and pointed, the longest uppermost, and springing from the front edge of the antennal pit, blunt and tooth-like ; pronotum furnished with nine long bristles, and spines on each side. Abdominal bristles in ove row only; the second row is represented by one or two bristles only, and are very small. This is another British species, mentioned in Verrall’s list. Curtis also records a flea from the hare (C. /eforis), and from the starling (C. sturnt). Leports appears to be the same as gontioce- phalus. The Pavicide tabulate as follows : Teen wiex eyes Gistinct: 2. Hystrichopsylla: densely spinose cheeks and clypeus. No eyes, or eyes indistinct. 3. Typhlopsylla: no eyes, or eyes indistinct. Te cE MeL No pro-thoracic comb posteriorly, 7vrctans. Posterior comb present. Head without black spines. Proth. comb with 26 teeth or more, Avium or galline. ” » hy Bit” 5 Sclurorum. ” y me uns sonteachiside, “7777acc?. » 9 ae Lore Yes fasciatus. Head with black spines. Epistome and cheeks with 6-7 black spines on each side, Canzs = felis. Post. margin of cheeks with 4 black spines, Gowzoce- Phalus = Leporis. * Ent. Mo. Mag., vol. xxvii., p. 170. 3-—2 36 AN ACCOUNT OF BRITISH FLIES. 2. Lyphlopsylla : 8 combs along the back, octactenus, Kol. 6. us 3 wy exactenus, Kol: Comb only on posterior margin of pronotum. 4 genal spines, muscu/t. 3 s assimilts. Three spines on the suture dividing ant. cavity from the front of head, gvaci/is. 3. LHystrichopsylla : Cheeks and clypeus densely spinose, obtusiceps. The geographical distribution of the “fleas” seems to be world- wide, occurring from the Arctic regions to the tropics. They seem, however, to flourish best in warm climates, where they swarm in every room. Darwin gives a curious episode respecting fleas on reach- ing the mountainous country nearCoquimbo. He says: “I enjoyed my night’s rest here from a reason which will not be fully appreciated in England ; namely, the absence of fleas! The rooms in Coquimbo swarm with them ; but they will not live here at the height of only three or four thousand feet.”* This, he states, cannot be on account of the trifling diminution of temperature at that height. They occur just as plentifully in the mountain chalets of Switzerland also as in the warmer valleys. There appear to be no records of fossil fleas, as far as I can make out. None seem to be recorded from fossil amber, as we might expect. Modes of Destruction : 1. Careful sweeping of carpets, mats, and rugs upon which animals are in the habit of resting, and instantly burning the dust, thus stopping the development of the ova. If they are allowed to hatch, the small larvz soon migrate into cracks and crevices, and are then difficult to dislodge. 2. Paraffin is found a good remedy for destroying the larvee as well as dispersing the adults, and should be applied fairly strong to all cracks and crevices where dust has accumulated. . The leaves of the feverfew are also said to keep away fleas; whether this is true or not I am unable to say. 4. The following method is taken from “Land and Water”: “Take a few handfuls of fresh garden mint, and strew them about the rooms, particularly under the beds. This plan I adopted when on the Neilgherry Hills with perfect success.” 5. For cleansing floors, etc., a solution of carbolic acid or paraffin * “Voyage of the Beagle,” Darwin, p. 344. Ow APHANIPTERA. 37 (the former hot) are suitable agents. There is, also, an old country method of a boiled concoction:of laurel-leaves, poured over the floor when boiling. No doubt the boiling water and the prussic acid in the leaves may have some effect. For animals, such as dogs, the same rule of cleanliness applies. If the kennels are kept well purified with insect-powder and carbolic acid, these insect pests soon disappear. In dogs very badly affected, a bath of gas-water, after having been sprinkled with insect-powder, is often very satisfactory, especially in long-coated dogs. Literature on the Aphantptera : 1, Annals of Nat. Hist., 1848. ‘‘The Common Flea.” West- wood. 2. Annals of Soc. Entom. de France, 1872. ‘‘ Metamorphoses de la Puce du Chat (Pulex felis).” Dr. Al. Laboulbéne. 3. Annals of Soc. Entom. de France, 1873. ‘ Observations sur les Puces, en particulier sur les Larves des Puces du Chat et du Loir (P. felis et P. fasciatus).” J. Kunckel. 4. “Die Flohe,” von Dr. O. Taschenberg. Halle, Max Niemeyer, 1880. 5- “‘Insekten-Kunde,” von Dr. Taschenberg, p. 127. 6. Hist. Nat. des Insectes, Aptéres, Walckenaer, vol. ii. 7. Insecta Britannica, Diptera, vol. ill. Walker. 8. British Entomology. Curtis. g. Arcana Nature, tom. i. Leuwenhoeck. to. Ann. Sci. Nat., 1832 and 1836. Dugées. 11. Nov. Act. Acad. Czs. Nat. Curios., vol. xvii. Bouché. 12. Brasil. vorzugl. last. Ins. (fig. 5), translated in Mag. Nat. Hist. vol. ix. Pohl and Kollar. 13. On the Affinities of the Aphaniptera. Nat. Hist. Re. Pro. ili., p. 9, 1856. A. H. Haliday. Note 1.—The “ Jigger.” Mr. Newton, Vice-Consul at Loanda, informs us that the ‘‘ Jigger ” was not known on the W. coast of Africa before 1872, but that year the ship Zhomas Mitchell went from Rio Janeiro to the port of Ambry, and the crew,on arrival were suffering from “ Jiggers.” These were quickly communicated to the crews of the boats and introduced on shore, and in a short time everyone had them in Ambry. They have since gradually spread along the coast. Mr. Newton continues to tell us that he has seen many natives without toes and in a dreadful state from allowing the eggs to hatch and burst and the wound to fester. The ‘‘Jiggers ” keep along the coast, and are seldom found in theinterior. They generally attack the hands and feet, but have been observed in all parts of the body, and are chiefly found in dy and sandy places, not in the damp. NoTE 2.—P. evinacet, p. 32, has a few, bristles or spines on the prothorax (not mesothorax), but no fringe. Note 3.—P. galling, p. 31. Mr. G. C. Bignell, F.E.S., has kindly sent me some fleas from house-martins’ nests. These are undoubtedly typical specimens of P. galline, and differ from those taken by myself from swallows’ nests in several points which will be given at the end of vol. i. CHAPTER IV. NOE MOAT O1G EE ReA® THE CECIDOMYID&. AFTER the short account of the Pw/icide, we now pass on to the chief sections of the Diptera, and proceed to describe the more important families of each section, commencing with the Nematocera. The characters of the two sections of the sub-order Orthorrhapha, viz., the ematocera and the Lrachycera, are as follows : Nematocera.* This section has the antennz composed of more than six joints, and the fundamental form is that of a thread. Two of the joints are known as the scapus, and the following those of the fiagellum. ‘The third joint, that is the first flagella joint, is never so distinguished as to render the succeeding joints accessories to it, the joints being formed in such a way that we cannot consider the flagellum as one joint, marked by annulations. Palpi composed of four or five joints. Brachycera. Antenne short, three-jointed. The two joints of the scapus likewise separated. Third joint remarkably developed and has a peculiar anatomical structure, which is most probably for sensorial functions. ‘The succeeding joints absent, or very few in number ; when present they are in the form of a bristle. In some genera the first joint of the flagellum is not enlarged, then the follow- ing joints are more numerous, and most seem to be sensorial in function. These joints are so closely approximated that they can almost be considered as one joint, marked by annulations. . The palpi are 1 to 2 jointed. Although the above characters seem to sharply separate these two sections, they nevertheless are so closely connected by intermediate types, that some cannot be satisfactorily placed in either division. The Xylophagide,t for instance, can be placed on the limits between both sections, and amongst the Nematocera the AZyphide are nearly related to the Brachycera. Se Videip ats. + Vide p. 20. a es eee NEMATOCERA. 39 (Cecidomyzide, Hal. Tipularize Gallicole, Meig. THE CECIDOMYID#& = 4) Cecidomynz, Rond. [cesidomites, Newm. Cecidomyzides, Zett. Fic. 6.—Catacha latipes. A, Ungues and pulvillus of C. Za¢zpes. This is one of the most important families of the Nematocera,* and contains a very large number of extremely minute insects, characterized by the following points: “ Eyes lunate, ocelli very often absent. Antenne moniliform, composed of thirteen joints in 9, 24 in g, at least, and ornamented with short verticillate hairs. Very few veins are present in the wings, which are often hairy. Thorax devoid of transverse sutures. Legs long, coxze short, femora elon- gated and thin, tibize destitute of spurs.” Taschenberg + describes the Cecids generally as follows : Extraordinarily small. Colours change in death. Head com- paratively large, proboscis short, palpi generally four-jointed ; rather large eyes, generally bare, ocelli absent in most species. Antennze long, often very long, globular or cylindrical, depressed or stalked, articulations varying in number according tothesex. Thorax arched, scutellumsmall. Abdomen cylindrical, eight-ringed. Legs very slender, tibiz without spurs, tarsi small, with one pulvillus (Fig. 6, A). Wings large, broad, rounded in front, decreasing at the root, edged with hairs, often hairy at the surface. The radial, discoidal, and anal veins are wanting, so that there are only three to five veins. Sub- * This family is included by Osten-Sacken in his 7yae Mematocera. + Taschenberg’s ‘* Praktische Insekten-Kunde,” 1880. 40 AN ACCOUNT OF BRITISA FLIES. costal and cubital often close together, postical often forked.* Between the cubital and postical isa vein-shaped fold. The little cross vein is long and often so crooked that it looks like the beginning of the cubital. The cross vein often found between the discoidal and postical is wanting in the Cecids. Rs SS Fic. 7.—Balancer of a Cecid. The “ balancer,” or “ haltere,” of the Cecidomyide (Fig. 7): Lownet divides the “ balancers ” or halteres of flies into three portions, viz., the base (extremity which joins the body), pedicle (or stalk between the two extremities), and globe (distal extremity). The base contains four groups, each group composed of rows of vesicles (as Keller and Lubbock name them), the number of rows varying in various kinds of Diptera. The two upper rows or “ridges” of vesicles, viz., those nearest the pedicle, are generally arranged in the form of two half cylinders, and the lower rows form a hemisphere. The grooves between the rows bear curved hairs. Lowne thinks that the vesicles are contained in sacculi, and that there are bright ‘corpuscles of high refractive power” beneath them. In the blow-fly there are altogether nearly 1,000 vesicles in each halter. The globe contains large vesicles of fluid. ‘The nerve of the halter divides into several branches in the base, and passing through the pedicle, ends in loops and nerve cells in the globe. The vesicles are supposed by Keller, Lubbock, } Lowne, and others, to be auditory rods, forming part of the hearing apparatus of Diptera. Lowne (who describes a similar structure in the sub-costal nervure of the blow-fly’s wing, believed by him to serve a similar purpose) remarks that, being beautifully balanced by muscles, the halteres are not much affected by the vibra- tions of the body, and are, therefore, well-fitted for the development of auditory organs. Owing to the extreme smallness of the halter in a Cecid (the object being almost invisible to the naked eye when detached from the insect), we have found it very difficult to discern the rows of vesicles * ist longitudinal vein = ‘‘ subcostal.” 2nd = ee ecubitalas 3rd 55 a posticales 4th = ‘* discoidal,” etc. Tas Anatomy of the Blow-Fly,” p. 96. { “Senses of Insects,” Sir J. Lubbock. NEMATOCERA. 41 under the microscope, and impossible to count them. Only a rough sketch of the balancer is therefore given here, the bulb being the part which joins the body, and some groups and rows of vesicles being indicated in the narrower part. The males are smaller than 9, and their abdomens have knotty pincers (Fig. 8) ; the females have pointed projecting ovipositors. Fic. 8—-6 Genita’ia of a Cecid. Larvie, fourteen-ringed, become pupz within the larva skin, or -are uncovered.* These characters are sufficient to separate the Cecidomyide. ‘The limits, however, between this family or ‘gall gnats,” as they are popularly called, and the ‘“‘ Fungus gnats,” or AZycetophilide, cannot be easily fixed, the genus Zygoneura, for instance, bridging over the two families, this genus showing combinations of characters found in both families; the cox being far less elongated, and the spurs of the tibize far shorter than in the AZycetophilide. Besides this, they have undoubted Cecid characters in the antennz, which are monili- ‘form with verticillate hairs, a character never found in “ fungus- * Winnertz figures larvae of C. Urtice and Tremude (Lin. Ent.), Pl. I., 1 and 2. 42 AN ACCOUNT OF BRITISH] TUG1ES. gnats.” But in spite of these Cecid characters, Zygoneura agrees closely with Sciara, which is a true Mycetophilid. Notwithstanding these few exceptions, the Cecidomyid@ are a well- defined family, and one that has a great number of extremely interesting points, both froni an entomologist’s and from an agriculturist’s point of view, while the student of biology will also find much of great interest, such as the parthenogenetic develop- ment of the larvee. The natural history of these minute insects has been studied in close connection with their classification. This is owing to the fact that one of the most important stages in their life-history is the formation of “galls,” in this respect resembling the Cynzpide, a family of small hymenopterous insects, which attack plants in a similar way. All the Cecidomyide are small insects, and not easily identified. Their wings are covered by minute hairs and scales, which very easily rub off. They are most easily identified by studying the “ galls” in which the larve live, and for this reason we are so well acquainted with many of the life-histories of the family. There are certain species which do not produce gall formations, but live upon cereals. Of these we must particularly note the Hessian-fly (C. destructor) and the wheat-fly (C. ¢ritic’), which are so destructive to crops. Perhaps no family of Diptera are so interesting as the one we are considering ; not only are they interesting as perfect insects, but their larval stage is, ifanything, of more importance, as in many cases it so well illustrates that curious phenomenon in the animal kingdom known as parthenogenetic development. It was first discovered and studied in these larvee by Wagner,* and has continually called forth a great deal of attention at the hands of embryologists. It takes place as follows : The female places her eggs under the bark of a tree, where they first develop into ordinary larva, but internally curious changes take place. The ovaries become fully developed and bud off eggs ;t these eggs live upon the visceral mass, and soon hatch into secondary larvee, which again give rise to another generation, and so on until as many as five generations of larvae may be seen in the old larval skin. In the following summer a metamorphosis takes place and the sexual generation appears. There are other interesting cases of partheno- genesis in the Diptera, but none so interesting as those of the Cecidomyia. * Zeitschr. f. Wiss. Zool., T. xiii., 1863; also Schneider, Zool. Beitrage, i. (3), 1885, p. 272; and Mecznikow, Z. n. Z., xvi., 1866, p. 407. + =Pedogenesis (7.ec., the production of ova by the immature animal, and is in the insecta always parthenogenetic). en NEMATOCERA. 43 The explanation of this alternation of asexual and sexual genera- tions is the same as that given to the phenomena observable in the Aphides. This parthenogenetic development has a very limited range in the animal kingdom, being found only in Arthropods and Rotifers. It has no doubt been derived in a secondary way from sexual repro- duction. Some most remarkable cases are found in insects such as bees and saw-flies, in which ¢’s are produced without any fertiliza- tion, contrary to the usual rule, where 9?’s are produced when no fertilization has taken place, and these give rise to further generations of females. Eventually through a change of climatic conditions and food both males and females are produced. The existence of sexual with asexual parthenogenetic reproduction has led to that remarkable phenomenon in the animal kingdom called “alternation of generations,” so typically displayed in the Ccelenterates and Annelids. These furnish us with the most simple forms of “alternation of generations,” viz., a sexual form giving rise to an asexual form which, by a process of budding, gives rise to sexual forms like the one from which it started. This form of alternation is easily understood. The ancestors of the species originally produced themselves sexually and by budding at the same time, but most likely at different seasons of the year. By degrees the two modes of reproduction became confined to separate indi- viduals, and then gradually the dissimilarity in habits caused their structure to become considerably modified ; and thus gradually a compiete alternation of generations became-established. A closely-allied mode to the one above (sexual and budding) is seen in the case of those animals where sexual reproduction alter- nates with parthenogenetic reproduction, or with larva that may produce sexually or parthenogenetically. The Aphides may be taken as an example of this. In this case the ova develop partheno- genetically in the oviduct of the female, and as long as warm weather and plenty of food remain this mode of reproduction continues, but as soon as these conditions fail, sexual (¢{ and ¢) individuals appear. We may assume here the capacity of the females for producing parthenogenetic young without the intervention of the male element has been found advantageous, and has been taken hold of and moulded by natural selection and has led to the permanent pro- duction of viviparous parthenogenetic young, which only change to male and female forms at the cessation of favourable conditions. The same explanation applies to the Cecidomyia larvze as mentioned above. 44 AN ACCOUNT OF BRIS TILES. The egg of the Cecidomyia is rounded at each end and slightly elongated, yellowish to white in colour, The period of hatching is extremely variable, some ova taking weeks to develop ; some can, by artificial warmth, be made to hatch in a few hours. The larva.—The food of the larva is mostly vegetable ; some live on decayed wood, others under the bark of trees, and some few are said to be saprophytic, but most are true vegetable feeders, living on the soft parts of leaves and stems of plants. A few have also been recorded from fungi, and some from pine- ‘cones (C. strobi). They each have definite plants to live upon, and are seldom found on widely-different genera. There are, of course, exceptions to this rule, as shown by Winnertz, who points out that C. sisymbrit inhabits a gall on Berberis vulgaris in May and June, and a gall on Nasturtium sylvestre from June to November. Again, there are larvee that live as guests* in the galls of other species. It is a general rule to find several larvae in company with one another. (D¢plosis with AZylesinus and Apion in the stems of Sarothrium scoparium.) The larvze mostly live inside the vegetable tissue and produce the so-called galls, destroying, stunting and deforming the tissues of the plants. There are also some that live outside the plants (as Dzplosis ceomatis) ; and others, as the Hessian-fly and Wheat Midge, that live in the axils of leaves and amongst the florets of wheat. As to the various deformations produced by these larvee, it is not possible to enter here into all the numerous varieties produced. They vary from rounded protuberances attached by stalks to the stems of plants to rugosities and swellings on leaf and stem, arresting the growth and often destroying the reproductive faculties of the plant by forming gall-like masses in the flower-heads. On leaving the egg-membrane the larvee (Fig. 9) are colourless and transparent, the alimentary canal being seen through the body-wa!l, often assuming a green appearance, derived from the vegetable food it has been consuming. The whole larva, as it advances in age, becomes opaque, and assumes a reddish appearance, or sometimes a yellowish colour. One striking peculiarity of these larve is the number of joints. Between the head and first thoracic there is placed a supernumerary joint ; to which segment this belongs we cannot say; it might belong to either the head or the thorax. Thus we have in these larvee fourteen joints instead of the normal number, thirteen. The head and mouth parts do not seem to be properly under- * Often called ‘ zzgudlines,” from the Latin znguzlinus, a guest, or sojourner. NEMATOCERA. 45 stood. The horny parts consist of a ring with two backwardly-pro- jecting processes, with a soft and fleshy labium passing through it. There are also two 2-jointed appendages above, the palpi of Ratzburg and the antennze of Osten-Sacken. On the under side of the larvze we at once notice a curious, horny appendage. This is called in America the “breast-bone,” and in England the ‘‘anchor-process” (Fig. 10). It is situated at the junc- tion of the supernumerary and first thoracic segment. This appendage varies in the different species ; the base is buried in the first thoracic segment, the elongated stem of the process ends in various forms, some being toothed and some serrated. Fic. 9.—Larva (A) and Puga (B) of a Cectdonyia, greatly enlarged (about 18 times). What is this process and what is its function? Neither of these questions can be satisfactorily answered. It is considered by some to be homologous to the pseudopods of Chironomous larvee. Osten- Sacken considers that the fourteenth segment is part of the head. This anchor-process, then, might be taken for the mentum, in analogy to the horny mentum of Tipularee larvee. Miss Ormerod considers that it is used as a scraper or digger to assist in acquiring the food from the stem.* The stigmata, which are horny projections, are normal in number * See also Mr. Enock’s opinion, p. 50, Tr. Ent. Soc., 1891. 46 AN ACCOUNT OF SRITISH FLIES. and position. One pair on the first thoracic, and eight on the first eight abdominal segments, the last segment being devoid of any stigmatic opening. In C. fini the last segment was considered to be stigmate, but this is not the case, the last segment being hidden under the eighth. The larvae may be hairy or armed with bristles, and may have fleshy caruncles along the back, or may be entirely smooth. The last segment may be armed with two curved processes, which are used in leaping, several of these larvee being noted for their saltatorial habits (C. xégra).* They are often very active, and this has been particularly noticed in rainy weather, and also during and after a thunderstorm. The larvae may also have pseudopods on their ventral surface. They do not seem to require much nourishment, moisture being essential to them. They produce the galls through some irritating function Fic. 10.—The Anchor Process of (1) Hessian Fly (C. destructor) and (2) of Wheat Midge (LV. ¢rztzcz), (from Miss Ormerod’s manual). peculiar to them, causing an abnormal flow of sap. Some species are seen, however, to be extremely voracious. They are generally found in companies ; as many as eight or ten may often be got from the galled flower spikes in which many live; on the other hand, single larvae only may be found, as in certain willow galls (C. clau- silia on Salix alba). : There are certain larvee that live as “‘ guests ” in the galls of other species ; whether these live upon the excreta of their companions or upon the sap is not definitely known. The same applies to species that live under bark ; they may live upon the excrements of other insects. M. Vallot mentions some that live upon Acar?, sucking their juices, and found under the leaves of Chelidonium majus. At the close of larval life the maggots may leave the galls and pupate in the earth ; but some species remain and pass the dormant stage in their old homes. The lives of the maggots vary in length. The larva -of the Hessian-fly (C. destructor), according to Dr. Lindeman, lives twenty-eight days, and then changes at the spot where it fed to a “ This is a character of the sub-genus Dz7losts, to which C. x#z%gra most probably belongs. NEMATOCERA. 47 brown flat chrysalis, known as a “ flax-seed.” ‘The larve of Cecids do not undergo many moults, and eventually form a cocoon. The history of this cocoon formation, if correct, is curious. Win- nertz absolutely denies that this cocoon is spun: he says it is generally formed by an excretion and not by threads. He observed one larva that in twenty-four hours was surrounded by a halo of white thread-like particles, resembling the spicules of crystals, the larva remaining motionless the whole time. There are often no signs of a thread in these cocoons, which are formed in a few days. Others have resinous cocoons, and some spin undoubtedly a silken thread. The larval skin is not always shed during transformation. This change from the larval to pupal state is marked by a change of colour in the maggot, the anterior segment at the same time becoming distended, and by degrees the rudiments of the wings, legs, etc., become developed, and eventually the full pupal state is reached. ; The pupe (Fig. 9) of the Cecidomyide resemble in some respects those of Sczara, and are usually brownish flattened bodies of small size, resembling seeds. The bases of the antennz are often produced into points, resembling horns. Behind these horns bristle-like pro- jections may be seen in most pupee—one pair on the head, and another on the thorax. Spinose processes may also be developed on the abdominal segments, all these processes helping the insect to work its way out of the gall or earth at the time of emergence. The length of pupation is very variable, warmth greatly hastening the development. Under unfavourable conditions the pupze may remain unhatched until the next year. Those of the Hessian-fly may be retarded by cold, but are not killed by a low temperature ; dampness is essential to their hatching, a dry cold being injurious to the ‘‘ flax-seeds.” Mention has been made of the injurious nature of the Cecido- myide. Of this there is no doubt; they, nevertheless, are beneficial as well as injurious. By their means a great many plants are fertilized ; owing to their small size they can enter plants that very few insects can enter. No better example of the fertilization of a plant can be taken than that of Aristolochia clematis, which is largely done by Cecidomyide. I have myself seen as many as five Cecids in a single blossom of this plant ; one, however, is the general rule. Fertilization takes place in the following way: This plant, which is a protogynous dichogamous plant, belongs to the family A7zsfolo- chiacee, and is widely spread over the globe, several species of the 48 AN ACCOUNT OF BRITISH FLIES. genus Azistolochia being cultivated in England, and one, A. clematis, which is a European species, has been found occasionally wild, but is not an indigenous form. Few plants outside the Orchidacee have become so modified for fertilization by insects as the one in question. The flowers are all brownish-green, contrary to what we should expect, as we are told in Darwin’s “‘ Origin of Species” “ that flowers have been rendered conspicuous in contrast with the green leaves and in consequence at the same time beautiful, so that they may be easily observed by insects.” And likewise that ‘if insects had not been developed on the face of the earth, our plants would not have been decked with beautiful flowers.” In this Aristolochia we have a decidedly inconspicuous flower, not only visited by insects, but having assumed most curious adaptations to ensure fertilization. It is strange that this family, which calls in the aid of insects more than most plants, should not have developed a more conspicuously coloured blossom to attract them during the time it has been forming those complicated habits and structures relating to fertilization ! Each of these greenish blossoms commences with an expanded lip. This passes into a funnel or throat (A), which is lined by hairs, so placed that they allow the entrance of an insect, but not its exit. This long funnel opens into a flask-shaped enlargement (B), in which are placed the generative organs. ‘This cavity is also lined by hairs, especially at the base, around the anthers. The stigmas (9) are placed above the anthers (¢), and curve over them, the anthers being surrounded by the hairs of the flask. Fertilization takes place in the following way: The Cecidomyia enters the throat and passes down it, the hairs being placed so as to allow its free passage. As soon as it enters the flask it crawls about until its back, which is laden with pollen, comes in contact” with the stigma, and thus fertilizes them ; upon this taking place they spring up and assume an erect position. At the same time the hairs of the flask collapse and the anthers dehisce. The insect then crawling down, gets the pollen upon its back. While all this has been taking place the hairs of the funnel have withered up, and the Cecid or other insect, laden with fresh pollen, flies away to another blossom to repeat its experiences. But this is not all; as soon as the insects are free from the fertilized flower, the lip of the corolla bends over the entrance to the blossom, and thus effectually stops another fly from entering on a useless mission. ‘The whole pedicel assumes a bent appearance, while the unfertilized ones are erect. This is, perhaps, one of the most curious adaptations that a plant | . | NEMATOCERA. 49 has undergone for fertilization by insects, and has called forth a great deal of attention. The figure below shows the modifications. The distribution of the Cectdomyide in space seems to be very great ; most regions of the globe furnishing examples of this family. They seem to extend into the Arctic Circle, but are more abundant as we approach warmer climes. Their distribution in time is limited, as far as we know, the tertiary ambers alone yielding their remains. From these, two extinct genera, Zithomyza and Monodiciana, Lw., have been described. The former belongs to the Anaretina, and the latter to the Cecidomyina. About twenty-three species in all have been described, amongst the sub-genera Lpidosts,* Dirhiza, Diplosts, Cectdomyia, and Asynapta, some from America and some from Europe. Zasvzoptera has also been found in a fossil state in Wyoming. Their small size "and fragile nature would naturally hinder their preservation. FG, 11.—-A7?stolochia clematis, showing method of fertilization. 1. Unfertilized blossom. 2. Fertilized. A. Funnel. 3B. The flask with generative organs. C. The ovary. The classification of the Cecidomyide is as follows. They can be divided, according to Loew, into two sub-families : A. Cecidomyina = Cecidomyine, Rd. Three or four longitudinal veins on wings, the last two often coalescing at the beginning of their course, forming a fork. Ocelli absent. B. Anaretina = Lestremine, Rd. Has a supplementary vein between the second and third of the Cecidomyina. This additional vein is furcate. Ocelli are present in most of this group.t * ** Bernstein-Fauna,” p. 32 Loew, descriptions of C. (Zfzdos¢s) incompleta and C. mdrutisstma. + Cectdogona has no ocelli. 50 AN ACCOUNT OF BRITISH FLIES. He makes three genera in A; viz., (i.) Cecédomyia, (11.) Spantocera, and (iii.) Laséoptera. The first he divides into several sub-genera. (i1.) Cecidomyia.* Antenne long and moniliform, or cylindrical; generally verti- cillate, 13-36 joints. Wings always very hairy, and have densely pubescent margins. Three or four longitudinal veins. ‘There are two types of wings. In the first type the third vein is forked, thus representing the third and fourth veins, which have united for most of their length. In some rare cases this fork may become obliter- ated. In the second type cf wing the four veins are separate and simple. We must note in these insects a curious longitudinal fold between the second and third longitudinal veins, present in most Cecidomyide. (ii.) Spantocera, Wtz. = Brachyneura, Ra. Antennee filiform, having no verticils, and composed of thirteen joints. Wings covered by scaly hairs. There are three longitudinal simple veins, the first running parallel to and close to the costa. The other two widely separate (Fig. 94). (il.) Laszoptera, Mg. = Lasiopteryx, Steph. Antenne composed of 16-26 joints, each joint being sub-globular, with short verticils. ‘The three longitudinal veins not so easily seen as in the above genus; the first and second run close together, and near the costa. There is a large space between the second and third vein (Fig. 104). Proboscis short. The following is a short description of the sub-genera of Cec7- gomyla : ( Dasyneura, Rd. Cecidomyia, Lw. = - | Rhabdophaga, Westw. Same number of joints in the ¢ antenna as in the ¢. The joints may be pedicelled or sessile. The second longitudinal vein reaches the margin of the wing before its tip (Fig. 14). | Phytophaga, Rd. ( Bremia, Rd. The antenna of +f = 26 to 27 joints); that of the 9 —14 toms. The joints are pedicelled. The second longitudinal vein reaches the margin beyond the tip. The joints of the antenne of the ¢ double the number of those of 2 (Fig. 24). Diplosis, Lw. = * As far as I can make out, there seems to be a great division of opinion as to what the genus Ceczdomyza is to mean; Meigen, Latreille, Macquart, Zetterstedt, and Walker, holding one opinion; Loew, Rondani, Westwood, Winnertz, O.-Sacken and Schiner, another. Taschenberg describes the genus as having sub- costal and cubital veins plainly separable ; postical vein forked. NEMATOCERA. 51 fTormomyta, Lw. = Angelinia, Rd. This sub-genus is distinguished by the gibbose thorax, which is often drawn over the head. ‘The second longitudinal vein ends as in the preceding sub-genus. Wings without lustre. ( Cylindrocera, Lioy. \ Fhyllophaga, Rd. Antenne with short hairs of equal length ; joints cylindrical and sessile ; no verticils. Same number of joints in ¢ and 9. Second longitudinal vein reaches the margin of the wing, beyond its tip. Wings shiny. Asphondylia, Lw. = Dirhiza, Lw. Joints of antenne sessile in both sexes. Second longitudinal vein hardly undulating before the cross-vein. Epidosis, Lw. = Forricondyla, Rd. Joints of antennz pedicelled. Second longitudinal vein is sinose before the cross-vein. The cross-vein runs obliquely, commencing at the root of the first longitudinal vein in the last two sub-genera (Fig. 3A). In the others the cross-vein commences in the middle of the first longitudinal. Asynapla, Lw.= Winnetsia, Rd. Has four distinct longitudinal veins—all other sub-genera having three—the last being divided. Reputed British (Fig. 44). B. The second section is not satisfactorily classified. Loew considers the members of this section as forming a sub-section of the Cecedomyide. Winnertz isolates them as a separate and distinct family between the Cecids and the Mycetophilids. Brauer places most in the Cectdomyide and some in the Mycetophilide (Zygoneura). The following are the more important genera of this section : Catocha, Hal. = Macrostyla, Wtz. Ocelli present. Wings hairy. Third longitudinal vein forked, the upper branch forming a single smooth curve. The ¢ has verti- cillate antennz, composed of sixteen pedicelled joints. ¢ antenne ten-jointed, joints moniliform (Fig. 5A). = . ( Campylomyta, Z.H. Campylomyza, Meig. = ; ‘ EGE’ | Neurolyga, Rd. Ocelli present. Wings hairy. Fourth longitudinal vein forked. Antennze 11-20 joints, moniliform in J, with pedicelled joints. Sub-moniliform, with sessile joints in 2 (Fig. 6a). 4—2 52 AN ACCOUNT OF BRITISH TLIEES, asi zinie, Mined = ( Mimosciara, Rd. | Yposatea, Rd. Ocelli wanting. Wings pubescent. Antennz moniliform in ¢, sub-moniliform in ?, 16 joints. First longitudinal being short, third forked (Fig. 74). Colpodia, Wtz. One species is reputed as British. The second longitudinal vein forms a curve before the cross-vein, and joins the margin beyond the tip of the wing (Fig. 8a). Cecidogna, Lw., antennze 11-jointed ;* JZicromyia, Rd., is another genus found in Britain, and given in Bergenstamm and Low’s work. Zygoneura, which shows certain affinities to the Ceccdomyide men- tioned before, and also to Sctara, one of the JZLycetophilide, is now included in the latter family ; but is no doubt a transitional form between the two. Avarefe is now placed in the Bzdionide. The following are the genera and sub-genera found in England, the names being those used by Verrall and in Bergenstamm and Low’s classification} : Lastoptera, Mg.; Cecidomyia, Mg.; Asphon- adylia, Lw.; Diplosis, Lw.; Hormomyia, Lw.; Dirrhiza, Lw.; Epi- dosts, Lw.; Winnetsia, Rd.; Campylomyza, Mg.; Micromyta, Rd. ; Catocha, Hal.; Lestremia, Mcq.{ Most of these are considered sub-genera of Cecidomyia by Loew ; by others as true genera. By tar the most important is Cectdomyia proper, which contains as many as fifty species indigenous to Britain,§ and amongst these by far the most interesting and important is the Hessian-fly (C. destructor), which we now proceed to describe, with other species of this sub- genus. (Dasyneura, Rd. | Rhabdophaga, Westw. Cecidomyia destructor, Say (the Hessian-Fly). The egg of the Hessian-fly, which is small and cylindrical, is described by some as being rounded at each end, by others as being pointed at each end,|| pale-orange colour at first, with reddish dots, becoming darker later and transparent the third day ; about ‘oz mm. long by ‘oo8 broad. ‘The larvze emerge on the fourth day. Accord- ing to Mr. Enock,‘' a female will lay from roo to 150 eggs; others. say as many as 280. They are laid on many separate plants of Sus-GENus.— Cecidomyia, Lw. = * This is now merged into the sub-genus Lestremia. Diomyza, Clinoryncha, Heteropeza and Tritozyga are other foreign genera. + Synopsis Cecidomyidarium, 1876, J. E. von Bergenstamm and Paul Low. t The following is a reputed British genus: Co/podza. § Ninety or more, if we include reputed and doubtful records. | ‘*Hessian-Fly Report of Department of Agriculture, U.S.A.,” p. 208, 1880-82. {] Trans. Ent. Soc. of London, June, 1891. NEMATOCERA. 53 wheat or barley, about eight in a patch, glued together by a sticky fluid. The greater number are deposited on the latest-developed leaves. The eggs are laid with the head end downwards, so that when the larvze are hatched they are prepared to crawl down the leaves and stem, and to establish themselves within the leafy sheath, generally at the second joint above the ground. The /arva is short, stout, cylindrical, and soft-bodied; about 2 mm. long when young, increasing to about 3 mm. There are fourteen segments, and indications of prehensile feet at the anal end. When first hatched the larve are transparent, showing the alimentary canal through the extremely thin body wall, often green in colour, owing to the colouring matter of plants. They change colour when pupating. The larva, when it has passed its feeding stage, develops a forked appendage, a horny short stem with two little projections, situated close to the head on the under surface of the second segment—the ‘* anchor-process.” ; In the case of the fly now under consideration, Mr. Enock has made the notable discovery that the larva, after it has finished feed- ing on the juices of the stem, with head placed downwards and inwards, turns itself completely round in its third stage, bringing its head upwards, anchor-process outwards, and that it uses the anchor- process to perform this feat. This turning movement takes place within the “fpupartum,” as the hard case, or skin, is called, which gradually forms itself around the larva, in its second stage, after the first, or feeding stage, is passed. This case is chestnut brown, and in size, shape and colour re- sembles a small flax-seed, so much so that this stage in the life-history of the fly is often called the “ flax-seed stage.” At first the puparia are smooth, but after a few days they become marked by longitudinal striations. There are also transverse markings on these “flax-seeds,” showing the old segmentation of the larval body. The ¢ puparium is narrower and paler than the 9. ‘The “ flax- seed” stage may only last five or six weeks, or the fly may remain in this state throughout the winter or longer. (The time of emer- gence greatly depends upon climatic conditions, cold greatly retard- ing their development.) The larva then works its way out of the puparium, casts its skin, and gradually changes into a true pupa. The ¢rue pupa is at first white, then pink, and becomes darker by degrees. It is oval, with rounded ends, the thoracic portion narrower than abdominal, limbs and body before emerging enveloped in separate cases. The pup 54 AN ACCOUNT OF BRITISH FLIES. have the power of climbing up between the leaf-sheath and stem until they find an opening through which the imago can emerge. A hard, sharp beak takes the place of the anchor-process, often used by the pupz for cutting an opening through the leaf-sheath. The fly breaks the pupal skin and emerges at the end of twelve or thirteen days. The ferfect Insect.— 9 Larger than the male. Length 3 mm. Eyes brownish-black ; front of head black, and clothed with dark, long hairs. Palpi yellowish, composed of four joints, partly covered by minute black scales, entirely covering the terminal joint. Antenne yellowish-brown to almost black, composed of seventeen joints, with short, black verticillate hairs.* The first two joints (basal joints) very thick; the first joint is cup-shaped, the second globular, the next smooth, cylindrical and elongated, gradually becoming smaller and terminating in a long, tapering point, longer than any of the preceding. The proboscis is minute and rose-coloured. Thorax black, with gray tints in certain lights, white hairs on the sides, and also scattered on the central region. Scutellum black, hairy. Halteres yellowish-pink, with occasional black scales. ‘There is also a light-red line running from the neck to the base of the wing along the side of the thorax. The abdomen is pinkish, or yellowish-brown, and is composed of eight segments. The first segment is nearly black, the remainder are marked by a large, square, black spot on each side. These black markings nearly unite on the seventh and eighth segments. The last two segments have a curious V-shaped marking, with two small lines, one on each side of it, and placed on a somewhat darker area than the yellowish colour of the segments.t The ventral sur- face is marked also by a line of black spots running down the centre. The oviduct is pale reddish-yellow, brownish at the tip, and composed of three joints. The last is pointed, and wthout lamelle. Legs pink to light red, clothed by black, scale-like hairs. Troch- anters black, coxze brown, other joints yellowish-white. Wings pink at the base, clothed by black hairs. The second longitudinal vein runs nearly straight, and then bends down and reaches the margin above the apex. 3 Smaller and more elongated than the female, 2 mm. in length. The antennz are composed of seventeen joints, as in the ? ; they * Enock describes the hairs as red. _t First discovered by Miss Ormerod. Dr, Meade, in his description, say she did not observe this V-shaped mark. NEMATOCERA. 55 are pedunculated, but longer than in the female. The terminal joint no longer than the others. Hair on the scutellum is also different to the female, being white Or gray. Abdomen black, pink at the end, marked in the same way as in the female, but the black spots have united, owing to the thinness and elongation of the body. A pink line is seen down the centre of the dorsal segments, and often a streak across each segment at its edge. The last segment is pink, and bears a pair of claspers of a brown colour ; between these claspers are situated the generative organs.* Legs lighter than in the female. Wings not so dark as the female, and longer in proportion to the size of the body. The colours vary as the insects grow; by some observers they are said to possess a reddish tinge when hatched (Enock). Miss Ormerod saw the changes taking place as described by Wagner: “from a golden-brown, through the shades of mulberry with transverse black bands above on the first six segments of the abdomen, on to the general brown tints of the abdomen,” etc.f Mr. Enock finds the 9 flies shy and retiring, hiding themselves under leaves and in holes in the ground, and resting on the earth, where their dark colour protects them. The first brood appears in August or beginning of September, and the second towards the end of April or May. Egg-laying continues through May and June. The eggs are laid either on wheat or barley; oats at present not being attacked by this fly. Rye is, however, subject to the injurious attacks of this most important insect pest. At present we are not aware that it attacks root crops in any way, nor pulse, such as beans, peas and tares. Couch grass (Zriticum repens) suffers largely from the Hessian-fly ; in Russia whole districts have been destroyed ; it is also known to attack “Timothy grass” (Phleum pratense) ; and at present, as far as we can tell, many more may be attacked ina similar way. Agri- culturists should note this, as thick, grassy hedges, etc., near corn- fields may form nurseries for the Hessian-flies to develop. It also shows how beneficial burning stubble is in destroying this pest. The ova are placed by the female a little above a node or joint of the wheat or barley stem. Dr. Griffiths says, in his manual of “ Diseases of Crops,” that the larvee establish themselves ‘just A Entomologist, 1887, p. 172. Fig. of male genital organs. —Meade. y ‘‘ Life-History of Hessian-Fly in Britain.” 2vtomologist, 1887, p. 9. 56 AN ACCOUNT OF BRITISH FLIES. above the second joint.” ‘This seems to be generally the case, but it is not at all uncommon to find them as high as the fourth joint, and as low as the first. ‘They never are present in the ear. The ‘“‘ribbon-footed corn-fly” (Chlorops teniopus) feeds in the ears of corn, and has very often been mistaken for the maggot of the Hessian-fly. The attack of this insect is easily seen in a field of wheat, the straw bending down just above the abode of the maggot or maggots, for there may be several in very bad attacks at one point. It is not unusual to find a gall, or swelling, above the infested part. The larve living on the juices of the plant weaken the stem, and although the ear and upper part of the straw may become stunted, the infested part becomes so weak that the upper part with the ear bends down, as if beaten down by rain and wind, thus doing immense damage to the crops. Hundreds of acres of wheat and barley are destroyed in this way in America, but at present we have not suffered much from its ravages, the loss in infested areas in England being from one to twelve bushels per acre. This insect, which is two-brooded in America, has only one brood in England, and so here we are only subject to one attack. Young autumn-sown wheat, which is so much devastated on the American continent, is free from the attack here. ‘This second form of attack is very different to the former. The maggot, which has developed from the autumn brood, lies just above the root, at the surface, and before assuming the “ flax-seed ” state it comes to lie between the leaves and the stalk. ‘This second form of attack may be known by the dark colour of the leaves, their great breadth, and the absence of the central leaf. ‘The whole wheat plant becomes stunted and rank- growing. ‘The first brood appears in May and June, the second in August and September. According to Professor Riley the Hessian- fly ‘is very injurious only under conditions where two annual genera- tions are pretty uniformly produced ; and he is satisfied that in England, as a rule, only one generation will be produced.”* ‘The same entomologist, in “Insect Life,” says that “there is very little danger of any such injury in England as is suffered in America and in portions of Continental Europe.” Whether this is correct time will show ; certainly the climatic conditions of our island are favour- able to its increase. The distribution of C. destructor is very wide ; 1n America it extends from the Atlantic to Kansas and from the Gulf of Mexico to the St. Lawrence, doing an immense amount of damage. It was known * Griffiths’ ‘* Diseases of Crops,” p. 114. NEMATOCERA. 57 in 1776 in America, and was said to have been imported by the Hessian troops, but this is most improbable. On the American continent it has flourished far more than in Europe, where it was first detected in 1834 in the Island of Minorca. According to Dr. Lindeman* it appeared in Russia in 1880. It is found also in Germany, Austria-Hungary, France, Italy, and Sweden. In England its first recorded occurrence was in 1886,+ when in July of that year “‘flax-seed” puparia were sent to Miss Ormerod from Hertford. Since then the attack has been shown to range from Cromarty to the Moray Firth and down the east coast ‘of England to Kent. In Scotland it has been discovered in Lothian, Perthshire, Haddington, and Berwickshire ; attacks have also been recorded from Northumberland. As we pass in a southerly direction the attack widens out. Lincolnshire, Cambridgeshire, Huntingdonshire, Bed- fordshire, and in some places in Northamptonshire it has been prolific. In Hertfordshire and some of the eastern counties very heavy attacks have also been recorded. In Hampshire it has appeared at Petersfield and Lymington ; at Goring Heath, in Oxfordshire ; at Salisbury, and in Kent and Surrey. This is a somewhat curious distribution, it seems, to keep to the sea-coast as much as possible. Perhaps Cambridgeshire and Lincolnshire have suffered from the worst attacks. In Ireland it has not yet appeared, and not farther north in Scotland than Cromarty, no records coming from Caithness or Orkney. This fly is subject to a number of parasites, and by their study we can safely assume that the Hessian-fly was imported into England from Russia, or is at least of European origin. The study of these parasites has been ably worked out by Lindeman} and Riley. The latter entomologist expressed an opinion that the parasites in England would be shown to be of Russian or European origin, and such is the case. The following are Russian parasites : Merisus intermedius, Tetrastichius Riveyi, Eupelmus karschit, Platy- * Bulletin de Ja Société Impériale des Naturalistes de Moscow, 1887. 7+ “Hlessian- Fly in Britain: Life- History.” vtomologest, 1887. Mr. Verrall does not consider the Hessian-fly a recent introduction, but had probably been here for a great number of years.—Prof. Riley considers that it has been re- cently introduced. It was not recorded by Banks, Curtis, Westwood, or Kirby, and by no economic entomologists—vde Ent., 1887, p. 327—but noticed by the founder at least eleven years ago, in the February number, 1876. + Die Pteromalion der Hessenfliege von Prof. Lindeman. Moscow, 1887. § Proc. of U.S.A. National Museum, 1885 (Parasites of the Hessian-Fly). 58 AN ACCOUNT Of BIAPISH HLLES, gaster minutus,* Semistellus nigripes, Eurysapus saltatus, Platygaster,. Sp. ? Four of these Dr. Lindeman found in a collection sent him. by Miss Ormerod, viz., S. nigripes, T. Rileyi, M. intermedius, P. minutus. There was also a species which agreed with Riley’s. description of the American JZersius destructor, Say.{ But this is also found as Ceraphon destructor in Germany, as mentioned in, Kollar and Kaltenbach’s works. From this we see that our attack has been derived from some European source, most likely Russia. Careful investigations on imported straw on the east coast seem to show that that was not the mode of introduction. It most likely came over in infested screenings, many other diseases and pests being imported in this way in foreign corn. Modes of preventing attack.—The early sowing of wheat and barley is strongly recommended in districts where the Hessian-fly has been at work during the last few years. In all cases it is found that late- sown wheat is more liable to attack than that sown early in the season. («) In the case of autumn wheat, the Zater it is sown the better. In America and Canada, where autumn-sown wheat is started earlier than in Europe, this is a rule especially followed. The reason being simply this: that if the wheat is not up until the flies are hatched and dead it cannot suffer from the attack, and for this reason we are free from the attack of autumn wheat, which in America seems. to do most of the damage. (8) Agriculturists should also pay great attention to the kind of wheat sown, for some resist the attack much better than others. The stout-strawed varieties should be chosen. ‘The following are found to resist the attack well: the “golden drop,” “ Rivett’s red,” “‘ square head,” ‘‘chaff red,” amongst the wheats; and the “ battledore,” “awnless,” and ‘‘bere” amongst the barleys. ‘The finer varieties. are all subject to attack. The thick-strawed varieties do not bend * Platygaster, which is a genus of Hymenopterous insects, lays its eggs within the eggs of the Hessian-fly, and the victims do not live beyond the puparium stage, as the larve of Platygaster devour them. The larve of Platygaster undergo the most remarkable changes, they scarcely being recognisable as insect larve ; in many respects the larvee resemble the Crustacean Cyc/ops in appear- ance. Anyone interested in this curious development should read ‘‘ Beitrage zur Erkenntniss d. Entwicklungsgeschichted. Insecten.” Ze@t. f. wiss. Zool., Bd. xix., 1869.—Ganin. This author (Ganin) has given a very good account of their development. Another account may also be found in Balfour’s ‘‘ Comparative Embryology,” 1880, vol. i., p. 345. + Entomologist, 1887. Parasites of Hessian-Fly.—Miss Ormerod. { ‘* Ergot” is largely imported in this way. § It is recommended in Canada and U.S.A. that wheat should not be sown until after the middle of September. NEMATOCERA. 59 down so readily as the others, and where they are healthily grown, they can resist any amount of attack. (y) The burning of stubble is an important point in aiding the destruction of these insects, and is a method that may be well adapted to other diseases. It may be done by commencing the firing at the borders of the field, so that the fire cannot spread out- wards, but gradually gets smaller and smaller as it approaches the centre. Dr. Packard, the American entomologist, however, is strongly of opinion that this remedy would be worse than useless, as large quantities of the invaluable parasites would be destroyed in the straw. (6) Deeply ploughing in the stubble can also be employed to great advantage, as the puparia, which are usually left in the stubble, cannot then develop satisfactorily. (When this is done the stubble should be cut high, so that the puparia are left.) (¢) Corn and straw that is imported should also be well examined, and if the “flax seeds” are discovered, even in small quantities, should be destroyed at once. (2) The stacking of infested straw should also be paid attention to. If it is stacked square, as hay, and firmly put together, a large number of the insects, even if they hatch, are unable to escape, and thus are not able to advance the disease. (n) The destruction of all rank-growing weeds and grasses in hedges around the cornfields ; for, as we have seen, the Hessian-fly infests certain kinds of grass, and most probably far more than we know. In this way the homes of many hundreds of flies may be destroyed. (6) Well-manured lands resist the attack, if a top-dressing of the following is added : ‘‘ Two hundredweight of nitrate of soda and one and a half hundredweight of salt per acre.”* Without this latter the crops will suffer from the attack. The choice of soil for wheat and barley growing in the infested districts should also be noticed. In hot and dry places the crops suffer far more from the Hessian-fly attacks than in less exposed and damp surfaces. I have seen fields in Cambridgeshire, in dry and exposed places, badly attacked, whilst others close by have almost escaped. There are said to be certain cuves ; but, as in all other cases, ‘ pre- vention is better than cure.” These cures are not satisfactory in the case of this pest. One of the most important is a “ dressing of gas- * Griffiths’ ‘* Diseases of Crops.” 6o AN ACCOUNT OF BRITISH FLIES. lime, which is said to destroy the larvee of the pest”; but neither this nor the application of soot and lime can be strongly recommended. Cecidomyia muricate, Meade. This species was discovered by Mr. Inchbald, and described by Dr. Meade,* in 1886, the perfect insect not being known before. ¢.—Head black, covered by white hairs. Face brownish-yellow, inner margins of eyes bordered by a yellow line. Palpi light yellow. Antenne composed of seventeen joints, blackish-brown, nearly as long as the body. Joints petiolate and verticillate, white hairs. Thorax blackish-brown, marked by three dark stripes, running longitudinally and gradually becoming less conspicuous as they pass backwards. ‘Thorax covered by white and gray hairs, especially at the sides and in two lines on the dorsum. Roots of wings bright red. Shoulders marked with a yellow spot. Scutellum black at the base, reddish-yellow towards the end and sides. Metathorax black. Abdomen dark reddish-brown, the first segment almost black ; white hairs upon all the segments, especially at the sides, and a few at the borders of the segments. A brown band runs down the ventral surface on a flesh-coloured ground. Last two segments narrow and testaceous in colour, the male armature also testaceous. Halteres brown, knobs clothed with patches of white hairs. Wings covered with a dark pubescence, veins clothed with scales, having a reddish tinge. The second longitudinal vein is straight and joins the costal in front of the apex of the wing. The under surfaces of the brown legs are clothed with silvery hairs. The knees and ends of tarsi pink. ? The female is distinguished from the male by the following - points: 1. The antenne smaller than g—about half the length of the body. 2. Joints of antenne sessile ; they lessen gradually as they approach the apex, the last joint being half as long as the pre- ceding one. 3. Abdomen lighter than the g. 4. Zhe oviduct long and slender, basal joint round, yellow; second joint elongated and brownish-black ; the last joint being long and slender, yellow at base, brown in centre, and pink at the extremity.. No terminal lamelle. The larve are found on Carex muricata, amongst the seeds and flower spikes. They feed “within the utricle on the embryo nucule, pupating in the spikelet.”+ In this position they pupate, forming a papery cocoon, towards the end of the autumn. * Entomologist, 1886. A New Cecid.—Inchbald and Meade. + Notes on Cecidomyide during 1886, 7t., 1887. NEMATOCERA. 61 The pupz are red, and hatch during May. The larvee may be found during July, and are mostly pupated by February. Cecidomyta clausilia, Bouché.* This species infests the willow (Sa//x alba), forming small, half- moon pads on the margins of the leaves; a single larva inhabits each pad, according to Bremi.f Bergenstamm says,} “these leaf- rollings are the work of a Phytoptus, and thus the Cecid-larve may be looked upon as inquilines.” According to Mr. Inchbald, in the paper mentioned, this is not the case, as far as his experience goes. /mago.—General colour dark-black ; abdomen dark reddish-brown ; head black, with a reddish spot and a tuft of white hairs on the face. Antennz 14-jointed in male; joints petiolated in g, sessile Ine Thorax black, striped and shaded with gray; roots of the wings red. Scutellum yellowish-white. Abdomen reddish-brown, covered by dark scales, arranged in irregular transverse rows. Genitalia of male small and black ; the oviduct of the female is long and slender, with no lainellee ; terminal joint yellow. Halteres with pale stalks and black knobs. Wings clear, slightly hairy ; second longitudinal vein straight in its whole course, terminat- ing before the apex of the wing. Legs pale brown, with white hairs beneath ; joints and ends of tarsi pink. This species was found by Mr. Inchbald, and described by Dr. Meade, it being unknown in the perfect state to Bergenstamm.§ C. stsymbrit, Schrk. = C. barbarea, Curtis. General appearance black; face reddish, with silvery-white pro- boscis and palpi. Antennz dark, composed of sixteen and seventeen joints in the ¢g sixteen only in the 9 ; longer than the body in the former, about half the length of the body in the latter. Thorax dark reddish-yellow at the sides ; wing covered by a dark pubescence, with dark veins ; transverse veinlet very obliqu:, joining the first longitudinal near its middle ; second longitudinal vein bent forward at its junction with the transverse veinlet, joining the border a long way from the tip of the wing. The second branch of the third longitudinal vein curved oliquely * Description of New Cecid. Lvztomologist, 1886, p. 213. + Bremi. Trans. of Swiss Nat. Hist. Soc., 1847 ; and also 475, p. ‘2, Bergen- stamm and Low. t ‘Synopsis Cecidomyiarum.” § Synopsis, p. 36, ‘‘ Imago unbekannt.” 62 AN ACCOUNT OF BITS TH HLIE,S. to the hind border. MHalteres dark, with reddish tinge, sometimes slightly yellowish. ‘The base of the femora yellowish beneath, tibize and tarsi shining white. Abdomen dark reddish-yellow, sometimes almost black. The oviduct is long, having the second and third segments yellowish-white ; no valves. The larvee form spongy galls in the stalk and inflorescence of the Barberry (Barbarea vulgaris) during May and June, and, according to Walker, from June to November, in the folded, blister-like galls of Nasturtium sylvestre, also in WV. palustre and Sisymbrium Sophia. The larvee undergo their transformations in the galls, and do not pupate in the ground, This species is figured by Winnertz,* and also by Loew in his “ Dipterologische Beitrige” (Figs. 8 and 9). C. Salicina, Bouché. ; Dh IC Gallarum salicis. Cecidomyta salicts, Schrk. = - C. Degeeri, eed \C. Argyrosticta, Macq. Black ; thorax with two stripes of whitish hairs. This insect is covered by silvery hairs, especially on the legs. In the male the joints of the antennee are 20 to 22 in number ; in the female from 22 to 24; half the length of body, longer in the male. The basal joints twice the length of their petioles. Wings pubescent ; trans- verse veinlet at the end of the basal half of the first longitudinal vein. Halteres dark. The larve of this willow Cecid form woody galls on the boughs and twigs of Sa/ix aurita, cinerea, caprea, and purpurea. ‘The larve pupate in the galls—not in the ground, as done by many other Cecids. Mr. Inchbaldt describes the galls as ‘: multilocular bosses on the upper twigs of S. cinerea.” They appear during June. C. acrophila, Wtz. Black ; abdomen on yentral surface pink, with flesh-coloured markings on the sutures ; sides of the thorax also pinkish. Antenne, 19 to 20 joints ; as long as the body in the @ ; joints and petioles of nearly equal length; in the ? the antennz are only half the length of the body ; both clothed by whorls of silvery hairs; wings silvery or whitish in some lights. ‘“‘ Transverse veinlet placed before the middle of the first longitudinal vein ; second longitudinal vein bent forward at its junction with the veinlet ; curved hindward from thence to its tip, joining the costal at some distance from the tip of the * «Linnea Entomologica,” 1853 (pl. ii., fig. 4). + Entomologist, 1886, p. 35. NEMATOCERA. 63 wing.” Legs brown, shining white underneath. Oviduct long and brownish yellow ; first segment flesh-coloured ; no valves. The larve live on Fraxinus excelsior, forming hollow elongated, pod-like aggregations, generally on the highest leaves. Before pup- ating they drop down to the earth and undergo their metamorphosis in the soil. The fly hatches in the spring. This species does not seem to have been figured; but has been described by Winnertz, Walker, Schiner, etc. C. betule, Wtz. The larvze of this species pass the winter in the seed-capsules of the birch, Betula alba. They pupate in the same place. Some- times two pupz may lie side by side in the same capsule. The perfect insect commences to appear at the end of March and during April. The perfect insect is dusky yellow, with the top of the thorax black ; the abdomen also occasionally dark. Legs pale yellow. Antenne dark brown, 12 to 13 jointed in ¢, apical joint with a very ‘short petiole ; in the @ twelve sessile joints. Wings limpid ; trans- verse veinlet placed a short distance before the middle of the first longitudinal vein ; second longitudinal nearly straight, joining the ‘costa near the tip of the wing; the second branch of the third longitudinal bending round to the hind border. Halteres grayish- white. ‘Third segment of oviduct white; no valves. We know of no figure of this species. ‘The metamorphosis was made known by Loew. Described by Winnertz, p. 234, Lin. Ent. C. saliciperda, Duf. (the Willow Fly) C. albipennis, Lw. Wtz. Walker. = 2C. terebrans, Lw. Rhabdophaga viminalis,* Westwood. The orange-coloured larva of the willow-fly may be found from July to the following April in the wood of young willows, under the bark—chiefly Sadix alba, but also on poplars.+ The ? lays chains of long yellow-coloured eggs. ‘The larve dig out short, irregular passages, forming gall-shaped swellings, and causing the bark to become scabby and to crack and burst. Bergenstamm says “ Ver- wandlung daselbst”;} but this does not always seem to be the case. The perfect insect is black, clothed with black hairs. The thorax is grayish, with four indistinct black bands; sides of the abdomen Lin Litt. LOSlsspe 3736 {+ Gard, Chron., 1847, p. 588. t+ Sy. Cecid., 70. 64 AN ACCOUNT OF BRITISH FLTES. with red markings. Wings dusky white and hairy; apex of the halteres also dusky white. Costal vein dark brown, second longitu- dinal vein straight ends at some little distance from the tip of the wing. ‘The transverse veinlet in g is before the middle of first longitudinal vein; in the 9? a¢ the middle of first longitudinal. Antenne yellowish-white, composed of 15 joints. Silvery hairs on the legs. These willow-flies only live twenty-four hours, and are found in many parts of Europe besides England. ‘They are subject to several parasites, including Zyryedymus salicis, Torymus salicicola, and Eury- tomus (Sp. ?). Cecidomyia nigra, Mg.* This species is placed amongst the reputed British Cecids in Verrall’s list. It has, however, been found in England in recent years, and can fairly be entered as a British insect. ‘The Rev. E. N. Bloomfield, of Guestling, showed me many of the larvee of this species a few years ago. They were remarkable for their saltatory powers. They affect the cores of young pears, destroying the pulp, and causing the pears, when only partly formed, to drop off. ‘They form blackened tunnels from their cavity in the pulp in all directions. Mr. Bloom- field found they used the ‘‘ Marie Louise” pears for their nurse, whilst we have found similar larvee in the ‘‘William” pear. They are yellowish-white in colour, and, according to Mr. Inchbald, pupate in the soil, spinning a papery cocoon enclosed in a case of earth,+ and also according to Bergenstamm. ‘This possibly belongs to the sub-genus Deflosis. C. brassicae, Wtz.1t=C. napi, Lw. The larve of this species live in the flowers and leaves of the cabbage (2B. oleracea) and in the pods of /Vapus and Chetranthus, Walker§ says as many as fifty to sixty live in one pod of the rape (B. rapa). The turnip (zapus) suffers largely from this larva in parts of England. ‘They appear in May and June, and change in the earth. Imago black. Abdomen red, black bands on the dorsum. Palpi white, antenne 15-jointed, with long whorls of hairs in the ¢ ; joints petiolate. In the ¢ the joints are sessile and the hairs much shorter, antennz not half the length of the body. Base of the halteres rose-coloured. Wings limpid, with black veins. First longitudinal near * Meigen, ‘‘Systematische Beschreibung der bekannten europaischen Zweiflii- geligen Insekten.” Aachen, 1818, pl. iii., fig. 11. + Entomologist, 1886, p. 35. ~ Lin. Ent., p. 231, Winnertz. Laboulbéne, Ann. Ent. Soc., Fr. 1857. § Ins. Brit., vol. iii., p. 84. NEMATOCERA. 65 the costa, transverse veinlet joining it near its centre. Second long. vein joining the costa far from the tip of the wing. Silvery hairs on the under surface of the legs. The /arve are milk white, with yellow intestine, the skin being granulated. Winnertz also says, “der Hinterrand des vorletzten Ringes mit einigen Borsten haaren bekranzt.” They are found in June. C. rosaria, Lw.= C. cinerearum. The larve form rose-shaped galls on the ends of the boughs of various willows, as Salix alba, aurita, Caprea, purpurea, cinerea, etc. Each larva inhabiting a separate gall, they metamor- phose in the rosette. The general appearance is dusky-black, with silvery hairs. Thorax with two stripes of silvery hairs, the sides and base of wings flesh-coloured, halteres reddish-yellow with brown tip. Antennze as long as the body in the 4, 20-22-jointed, sometimes as much as 24-jointed. Palpi yellowish-brown. Wings gray, iridescent, with blackish-gray pubescence. Costa and second longitudinal vein thick and black, the latter especially in the middle, and ending hardly in front of the tip of the wing. The second branch of the postical curved obliquely to the posterior border. In the 9 antennz 22-24-jointed. Winnertz says :* After death the colour of this insect is blackish or dusky-brown to black, with reddish-yellow bases to the wings. C. taxi, Inch. No cocoons are spun within the close-fitting nest of whitish leaves composing the interior of the gall. Pupa 1 lin. long, notched between thorax and abdomen, reddish, eyes black. The pupa passes up the tract of the gall, and the white pupal skin remains with the “ feeler ” sheaths. The zmago is between C. rosaria and riparia. They live only two or three days. An échneumon is parasitic on this species. 'C. urtica, Perris, “The Nettle Gnat.”t This species forms pale green hairy galls in the stem and leaf of dioica (the nettle). June to September. A single larva inhabits each gall ; the first segment very slender; second broader, one-twelfth as broad as the third; the fourth to the seventh each a little broader than the preceding ; the eighth is the largest ; the segments then decrease until the fourteenth. No cocoon is spun. They pupate in the ground. Pupa.—Forehead broad, armed on each side by a protuberance ; respiratory pointed tube behind each eye on the thorax ; yellow, tips * Lin. Ent., i., fig. 17; ii, fig. 13; iii., fig. 1; also vol. ii, fig. 23,in Bremis’ ‘* Beitrage zu einer Monographie der Gallmucken.” 7 Larva palpi (figs.), Lin. Ent, T. 8, Taf. 1. 66 AN ACCOUNT OF BRITISH FLIES. fuscous. Head fuscous. Wing-cases pitch black; antennze and legs black ; abdomen dirty yellow. Jmago.—Tawny, head yellow. Thorax has three brown stripes. Wings with dark borders. Halteres brown, yellow at base. Abdomen dirty yellow, black hairs. Legs black, femora at the base, and coxe yellow. C. terminalis, Lw. = C. fragilis. Twenty to thirty ova are laid on shoots of Salix fragilis. The larvee, which are yellowish-red, live in bloated galls, and live fourteen days. They pupate in the earth. When the larve have left the shoots, many scars appear between the healthy and the galled parts (=woody cells). The same process takes place which takes place at the fall of the leaf in autumn. ZImago.—Brownish-black ; antennze brown or yellow at the base ; 1g-jointed in g, 16-jointed in 9. Abdomen tawny beneath. Ovi- duct long, last two segments yellow. Costa of wings thick, deep black ; veins dark brown; transverse veinlet, situated about the middle of the first longitudinal vein; second long. vein curved towards the tip, ending at some little distance in front of the tip of the wing. C. campanule, Mill.—Larvee form galls on the seed vessels, and live also in green galls (axillary), developed from buds, or may be in terminal clusters on C. rotundifolia. Red larvee, with first segment beak-like. /mago unknown. C. bursaria, Bremi. Galls on Glechoma hederacea ; they are tubular bodies, with one pale larva ; when full fed the tubes become detached and fall. Fig. 12 (2). ZImago.—Crown of head raised conically. Reddish-yellow ; thorax has three confluent black lines and dark gray hair. Abdomen dark brown. Palpi yellow, crown black. Antennz brown. 18-jointed, petioles shorter than joints. Legs blackish-brown, whitish beneath, yellowish at their junction with body. Wings gray, scarcely iridescent, dark thick gray hairs. Antenne of ? shorter than 2, petiolate as in do. Oviduct very long and yellow. C. veronica, Bremi= C. chamedrys, Inch. The larve form tufts of leaves, forming a hairy pouch on the barren stems of Veronica chamedrys. Fig. 12 (5). The larve change in these nests. Pupa figured by Winnertz in “ Linnzea Ento- mologica,” Taf. 1. C. Crategi, Wtz. = ZT: oxyacanthe, Schk. In white-thorn hedges we often see the shoots terminated in tufts nd knobs; each of these is a gall tenanted by several of the larvz NEMATOCERA. 67 of this fly. They sometimes pupate in the leaf-tufts of C. oxya- canthus and coccinea, sometimes in the earth. Imago black, with yellowish palps. Antenne 16-jointed in ¢ ; 15-jointed in ?. Oviduct long, and yellow at the tip. Sides of thorax and meta-thorax flesh-coloured. Abdomen flesh-coloured, with black bands. Halteres white. Wings hyaline ; black pubescence and costa. Second long. vein bends forward at its junction with the transverse veinlet, then, passing in an almost straight line, joins the costal a little distance from tip of wing. Length, 2 lin. C. gal, Wtz.= C. molluginis, Lw. The larvze live in the blister-like galls of the flowery stalks of Galium mollugo, uliginosum and verum. They pass to pupal state in the earth. Jmago.—Yellow, head brown, tip of the palpi yellow, three dark bands on thorax, pectus shining. Wings limpid, veins and costa dark. Abdomen tawny, with black bands. Legs silvery underneath. Antenne in ¢ 17-jointed, 16 or 17-jointed in 2. Oviduct long and yellow. Length, # lin. C. pyri, Bouché. Pear trees are affected by this cecid, especially young trees. The larvee form and live in the rolled-up borders of the leaves, and pass to the earth to metamorphose. The imago is dark brown, with limpid wings, and tawny palpi. Transverse veinlet joining the middle of the first long. vein; second branch of the third longitudinal curved to the hind border. Length, 1 lin. C. Persicarie, L., infests the leaves of Lolygonum amphibium and Persicarie. ‘This is a black species, with a flesh-coloured abdomen, with dark hairy bands. The larvz may be found in July. C. subpatula, Bremi. C. Euphorbia, Lw.= { 4 ; C. capiteana, Bremi. According to Walker, the larvee of Luphorbie live in the tips of the leaves of Euphorbia Cyparissias. Perris,* in his account of the “Insectes du Pin Maritime,” says, “L’extrémité des tiges de 7 Lup. amygdaloides.” They pupate in the galls. Bremi figures the galls, wings, palpus and antenne.t Imago.—Black ; antennze fuscous, 16-jointed; the abdomen is flesh-coloured, with bands of black, which in the ? are hairy ; wings with dark pubescence ; transverse veinlet, which in some specimens is very indistinct, is situated at the middle of the first longitudinal vein. Second longitudinal nearly straight, ending near tip of wing. * An, Ent. Soc. Fr., 1870, p. 179. t Mon. de Gallmucken, pl. i., figs. 2, 5 and 7; pl. ii, fig. 25. 5—2 68 AN ACCOUNT OF BRITISH FLIES. Legs almost black, white beneath. Oviduct long, the third segment yellow. Male genitalia dark. C. galeobdolontis, Wtz.* = C. Strumosa, Bremi. The larvee live in the stalks of Gadleobdolon luteum, and form woolly galls. The description of this species is taken from Inchbald’s paper quoted below. ¢d Antennz with joints not pedicelled as in the 9. Wings limpid, gray pubescence in both sexes, the anal fork extending to the inner margin, more deeply coloured in ¢ than in 9. MHalteres darker (than ¢). Abdomen prominently forcipated. Legs longer in com- parison of its size. ? Antennz fuscous, 13-jointed, pedicellated. Thorax with disc pale fuscous. Halteres pale yellow. Oviduct pale yellow. Bremi in his monograph gives a good figure of the gall of this species (Pl. II., Fig. 26), and says concerning it: “In den gallen, welch ich dieses Jahr Ende Februaris fand, und welch vorziiglich gross und ganz frisch waren beobachtete ich die Larren bereits eingesponnen, aber noch nicht in nympten verwandelt.”t The imago appears in May and June. C. salicina, Schrk. = C. Frischit, Bremi. Imago.—Brownish-black ; face and palpi brown, yellowish bands on the side of thorax. Abdomen pinkish-brown, with black bands on the dorsum ; tawny beneath in the 2. Costa of wings thick and almost black ; second longitudinal vein very nearly straight, ending near tip of wing. Antennze, 16-17-jointed in J, as long as body; in the ? always 16-jointed, about half the length of body. Legs with silvery hairs on under-surface ; halteres white, gradually becoming dusky at the apex. Walker says, “The larvee live in the withered tips of the young shoots of Salix Caprea and S. alba, and also according to Muller.” They live in the young terminal leaflets of the shoots, which wither away and form a bud-shaped nidus, three to eight larvee in each. C. serotina, Wtz. The larvee live in the tops of the shoots of //ypertcum humifusum ; they drop to the earth before pupating. ZImago. — Blackish-brown; head, antennz and palpi brown; antenne, 16-jointed in @ ; 16-17-jointed in ¢. ‘The halteres are pure white in the living specimen, drying yellowish white. The abdomen of ¢ is sometimes tawny; each segment havimg_ black hairs on the posterior border; in ? the abdomen is flesh-coloured, * For more detail refer to Ent. W. Int., 1861, p. 69. + See Ent. W. Int., 1861, p. 56. + Ent. Mo. Mag., vi., 1869, p. 109. NEMATOCERA. 69 with hairs the same as inthe ¢. The oviduct elongated and white, or light brown, the ¢ genitalia brown. The first longitudinal vein very near costa. Second longitudinal vein joins the costa some way from the tip of the wing. C. cardaminis, Wtz. The larvee of this Cecid feed on the flowers, etc., of Carvdamine pratense and amara, and destroy all the parts they attack, usually picking out those plants that grow on damp and spongy ground ; the white amara often assuming the purple hue of Avatense through the action of these insects. ‘They change,to the pupa state in the earth. The zmago is black; thorax with three dark bands on a light ground colour; scutellum sometimes pinkish; abdomen tawny ; 16-17-jointed antennez ; in the ¢ the petioles of the joints near the base are short, those in the middle one-fourth shorter than the joints, antenne as long as body; in @ they are much shorter, and the abdomen is rose-coloured, with dark-brown or black hinder borders to the segments. Wings darkly pubescent ; brown veins ; first longi- tudinal vein very near costa; second longitudinal vein bending forwards at its junction with the transverse veinlet, and joins the costal at some distance from the tip of the wing. Inthe ? the second longitudinal is straight,from the transverse,veinlet to the border. C. heraclei, Ktb. Concerning this species, Low and Bergenstamm* say the imago is unknown. The larve are social and live on the leaves of Heracleum Spondylium, and pupate in the ground. Ca (Cc. strobilina, Bremi. (C. saligna, Hardy. The larvz of feterobia live in the ¢ flowers and in rosettes on the leaves of Salix amygdalina. The larve mentioned by Perrist seem to be referred to this species. Concerning the galls he says: ‘ Daris ce feutre vivent de nombreuses larves de Cécidomyie.” They pupate where they live. They also live as “ inquilines” An the galls of C. rvosarta. The zmago is dusky brown to black; abdomen tawny beneath ; scutellum and end of thorax pinkish. Legs fuscous, paler on under surface. Antenne of ¢ 17-19-jointed; 16-jointed in 2. Oviduct long, last two segments yellowish-brown. Costa of wing very thick and dark ; transverse veinlet pale, meeting the first longitudinal about its middle ; second longitudinal vein generally straight. Second branch of third vein curved so as to form an obtuse angle. = Sys (tesa ob ye + An. Ent. Soc. Fr., 1870, p. 180. 70 AN ACCOUNT OF BRITISH FLIES. C. pleridis, Mill. = C. filicina, Kief. Imago unknown. Miller describes the larvee as reddish in colour, living in the “rolled” and “laid down” leaflets of the fronds (of Pteris). One larva in each leaflet. The leaf-rolls are at first green, then they become cigar-shaped and reddish, and as soon as the larvee pass to the earth they become black. Perris* describes the habits as follows: ‘‘Au mois de juin, en observant avec soin les feuilles de la grande fougtre, Preris aguilina, on remarque ¢a et la des folioles roulées en dessous d’un peut cété, la partie roulée €tant ordinairement brunatre, ce qui la rend plus apparente. Si on la déroule avec précaution on met & découvert une larve Cécidomyie d’un blanc rosé.” C. quercus, Lw. ; . C. roboris, Hardy. CPEB Deen C. reaperiens, Bac le . npflexa, Rudow. Jmago unknown according to Bergenstamm. Hardy gives an account of this in the “ Scottish Gardener,” iii., 1854, which I have been unable to obtain. The larvze are said to live chiefly in the leaves of the oak ; the lobes of the leaf being folded and laid down on the under side, forming a hollow for two or three larve. The folds are paler than the leaf. The larvee pupate in the earth. C. thalictri, Traill. As far as I can make out this only appears to have been mentioned by Low.t Bergenstamm says, “Imago unbekannt.” The larvae live in the deformed fruit of Zhalictrum. Guilin See C. limbivolens { Maca, C. excavans The zmago likewise unknown. Concerning the larve Walker says: “In June the gallst of C. “#/i@ are not uncommon on the young shoots growing from the stumps of lime-trees by the banks of the Wye, near Chepstow. They are round or oblong, green on one side, bright red on the other. Some of them contain more than twenty separate cells, each inhabited by one larva. The latter is about one line of length, of a bright yellow colour, and has the faculty of leaping, like the larva of Prophila. It is full grown in the third week in June.” Bergenstamm says: “ Die Larven leben gesellig in dem nach oben eingerollten Blattrande von Zilia europea.” * Tr. Ent. Soc, Hr, 1570sp sso: + D. B. iv., 1850, p. 30. { Ins. Brit. Diptera, iii., p. 130. Bremi in his monograph figures the galls of C: tiliacea on the leaf of 7. Europea in several stages. s NEMATOCERA. ai C. Tornatella, Bremi. The larvae produce smooth light green, nearly cylindrical one- celled galls, on the top leaves of Fagus sylvatica, one larva in each gall, in which it pupates. Jago unknown, Fig. 12 (1). Fic. 12.—Galls produced by some Cecidomyide.—1. C. Tornatella on Fagus sylvatica ; 2. C. bursaria on Glechoma; 3. C. ulmarta—a =under-surface ; b=upper-surface; 4. C. marginemtorguens on Salix viminalis; 5. C. Veronice on Veronica, sp. ; 6. C. Fraxint. 72 AN ACCOUNT OF BRITISH FLIES. C. trifoltt, F. The larvz live in the united leaflets of Trifolium pratense and pupate there. This species is described and figured by Low.* C. ranunculi, Bremi. The “ Buttercup Gnat.” The larvee of this gnat live in the leaves of Ranunculus bulbosus and Zrifolium pratense. The zmago.—Head yellow, with some brownish markings; crown, antenne and eyes black: antenne in the ¢ 13-jointed; joints irregular, spherical; gray hairs. Thorax reddish-brown to black, sides and pectus yellowish ; wings gray ; halter steel-gray ; head long and dark. Abdomen tawny, dark bands on the dorsal surface. C. rhododendri, Vallot. Vallot + gave an account of the ‘‘ Rhododendron Gnat” galls some time ago. The larve live in bud-shaped pustules on the upper twigs of the Rhododendron. The imago appears to be un- known. C. rosarum, Hardy = C. rose, Macq. and Bremi. Bremi { in his monograph figures the galls produced by the larvee of vos@ as swellings on the back of the leaves of Rosa incana, Hardy,§ who describes this species, also gives a vague account of the larve of some rose parasites, but the species are not definitely stated. Jmago.—Small, black, and shiny ; posterior margin of thorax, base of wings, apex of scutellum and metathorax may be flesh-coloured ; abdomen pinkish, with black markings on the ventral surface. Legs long and slender. Costal and first longitudinal vein dark. Antenne 14-jointed in ?, black, short, and slender: joints surrounded by numerous long verticillate hairs. Halteres light. Length 14 lin. C. prunt, Kitb. Moncreaff || describes the galls as “ boat-shaped ” bodies, and bred from them a number of parasites, as Callimome macropteris (Walker). C. ulmaria, Bremi. This gnat appears in August. The larve live in wart-like galls on and under the leaves of Sfir@a ulmaria. The galls are hood- *V. z. b. G., 1874, p. 143, pl. ii, fig. 4.—F. Low. + Mém. Acad. Se. Dijon, 1836, p. 190. ~ Mon. der. Gallmucken, pl. ii., fig. 31. § An. and Mag, Nat. Hist., 1550, p. 186. || Antomosogzst, 1870-1871, p. 240. NEMATOCERA. ie shaped on the under surface and pale in colour. I once found many on the Meadow Sweet, near Eastbourne. The metamorphosis takes place in the gall, Fig. 12 (3). /mago.—Brownish-yellow, head yellow, antennze and palpi brown, some faintly yellow. Thorax marked by three dark-brown stripes. Abdomen tawny, with bands of dark, dense hairs. Legs dark brown, lighter beneath. Wings dusky. Transverse veinlet indistinct, meeting the first longitudinal near its centre ; the second longitudinal vein joins the costa far from the tip of the wing. Halteres yellowish- brown. Oviduct long; first segment reddish-brown, remainder yellow. Length } lin. Kidd* describes the gall as follows: “On the upper side of leaf the gall is hemispherical, nearly smooth and pink ; small, size of mustard-seed ; on the under surface the gall is produced into a snout-like cone and is pubescent.” C. lathyri, Fefld. The larvee of this gnat are social and live in galls deforming the young shoots of Lathyrus sylvestris. Some metamorphose in the galls, others in the earth. The zmago appears to be unknown. C. marginemtorquens, Wtz. Bremi. The larvz live in the deformed leaf borders of Salix viminalis, and pupate there. They are gregarious.} The leaf-borders become infolded and swollen, generally in elliptical patches, but sometimes extending all around the leaf. When young these deformations are variegated with red, yellow, and green, Fig. 12 (4). The zmago is black ; face, sides of the thorax, scutellum and metathorax tawny. In the ¢ antenne are 15-16-jointed, as long as the body. In 9 antenne 15-jointed, only half the length of body. Palpi pale yellowish-brown. Abdomen yellowish-brown, with broad black hairy bands on its dorsal surface. Wings covered by darkish hairs, costa dark, transverse veinlet pale, situated in the middle of the first longitudinal ; the second long. vein joins the costal at some distance in front of the tip of the wings. Legs dusky-brown, hairs white, changing to yellowish-brown in death. Oviduct long and slender at the end ; first segment broad and dark, remainder lighter in colour. © C. medicaginis, Bremi.} The larve live on Medicago sativa, forming a deformation between leaf-stalk and stipule ; they are gregarious, and pupate in the earth. * Ent. Mo. Mag., 1868, p. 233. + Miiller, Zzt. Mo. Mag. vi., 1869, p. 109, and Bremi, Mon. Gall-, 1847, pl. ii., fig. 32. + Mon. Gall., p. 17, pl. i, fig. 16.—Bremi. 74 AN ACCOUNT Of BRITISH FLTES, C. onobrychidis, Bremi. The larvee live gregariously, and, according to Bergenstamm, “in hilsenformig zusammengefalteten Blattern von Astragalus onobrychis und asper, Medicago falcata, sativa, lupulina und Onobrychis sativa.” They pupate in the ground. Bremi gives a description of this species which answers nearly to the following : Head black, also the antennz, which in both sexes are strongly hairy ; in the ¢ they are 14-jointed and as long as the body, the spherical joints being far apart ; in 9 antennz only half the length of body, 12-jointed. Thorax dark and shiny ; sides of thorax and pectus reddish, halteres also reddish-brown. Wings limpid, nerves deep black, first and second longitudinals strong, pubescent. Legs brownish-red, tarsi pale. The ? is stout and reddish, each segment having a black band on it; ovipositor thin and pointed; the ¢ is slender and almost black, on account of the development of the black bands on the abdomen ; ventral surface of abdomen tawny in both sexes. C. foliorum, H. Lw.=C. fulcorum, Macq. This is a somewhat rare gnat, the larve living in a small-sized gall on the leaf of the wormwood, Artemista vulgaris. The zmago.— g brown; bases of wings and body red, the latter having two rows of dark spots. Antenne 15-jointed. Wings brownish-gray, first longitudinal vein very strong, second quite straight, ending near tip of wing; wing fold like a vein. Legs slender and brownish. Points of the tarsi brown. Ican find norecord of the 9. C. plicatrix, Lw. The larvee live gregariously when young, and curl up the leaves of Rubus cesius and pass to the ground before metamorphosing. Imago.—Dark brown, sometimes with a reddish tinge. Abdomen red, with dark brown rows of scales. Antenne 14-jointed; each joint has a double row of hairs, the upper row the longer ; antennze red at base, brown above, joints sessile in 9. Wings short and broad. Third longitudinal ends a long way in front of tip of wing. Legs brown, not very slender. The following are also British species belonging to this sub-genus : C. pilosella, Binnie.=C. potentillc, F.C. viole, F.C. alpina, Lw. C. tubicola, Keif. — NEMATOCERA. 75 Sus-GEnus.—Diplosis, Lw. D. coniophaga, Wtz. = C. oidit, Hardy (Scot. Gard., 1854, p. 170 [?]). The larvze of this species live on the leaves of various plants, especially on the following: Betula, Populus, Rosa and Salix ; Bergen- stamm and Low also give Cirsium and Lactuca. Walker says “ they live with D. Ceomatis* on Ceoma miniatum, on the fallen leaves of Rora, and feed on that fungus.”t They feed on the spores of the fungi, and pupate in the ground. The zmago is yellow, the dorsum has three brown markings ; abdomen, each segment has white hairs upon the posterior margin ; legs brown; wings transparent, with thick gray hairs (Schiner) ; transverse veinlet joining the middle of the first longitudinal vein. 2 to 2 lin. § Tipula lott, Deg. Cecid. loti, Meigen. The larvee of this species have the power of leaping well de- veloped; this saltatorial habit seems common to this sub-genus. Low remarks ‘that all such larve belong to the sub-genus Diplosis.”t If this is the case, C. migra belongs here. The larve of Zoti live in the flowers and in the husks of the seeds of Lotus corniculatus, Medicago sativa and Vicia cracca. Many larve may live in the same flower-head and form curious gall-like deformations. They pupate in the ground. Jmago.—Blackish-brown ; neck and scutellum dirty whitish-yellow ; scutellum with yellowish little hairs. Wings have a dark pubescence and brown veins, dorsum has two rows of whitish-yellow hairs. Ovipositor large, black, yellowish in parts. DP. loti, Deg. = D. tremule, Wtz.—“ The Aspen Gnat.” _ § Tipula populea, Schrank. l Cecid. polymorpha, Bremi. The laryze|| of the “‘ Aspen Gnat” seem to form two kinds of galls; the first are formed on the leaves of Populus tremula—these are red galls the size of a pea—the second kind is the well-known gall formed on the leaf stalk: each gall is inhabited by a single larva, which pupates in the ground (Winnertz). Imago.—Dorsum blackish-brown, with two rows of whitish-yellow * Described by Walker, but only considered a reputed species by Verrall. The pout brown spots on the white wings easily distinguish this species from D, cozzo- prhaga. + Ins. Brit. viii., p. 106. ‘ Rora’ being a misprint evidently for Rosa. + Mon. of N. American Diptera, Osten-Sacken, pt. i., p. 183. § Vide note at end of Chap. IV. | Vide pl. i., fig. 2, vol. viii., Lin. Entomologica. 76 AN ACCOUNT OF BRITISA FLIES. hairs ; abdomen dark brown, with thin, flesh-coloured incisions and white hair. Posterior half of seventh ring, and the rest of the abdomen, flesh coloured; QJ genitalia black; ? yellow. Wings large, gray, with thick biackish-gray hairs, third longitudinal vein bending in an almost straight angle to the posterior edge ; r to r4 lin. ' D. tritici, Kirby.— The Wheat Midge.” This is a very interesting species, on account of its being so in- jurious to wheat, etc., and therefore we deal at greater length with this than with most species. The eggs are transparent, cylindrical, rounded at both ends, four times as long as broad ; they are laid in little heaps of six to thirty in the inner bloom of the wheat, close to the embryo grain. The /arve hatch in eight or ten days, first transparent, then yellow, changing to orange. Composed of 14 joints, the last cut out and curved, with four little teeth. When it wishes to push itself forward, it first curves itself round and holds on to some firm support. It feeds on the germs and flowers of the wheat, and seems to possess the power of jumping to the ground, where it buries itself from one to five inches deep for about fourteen days, after which it changes to a pupa. Before burying itself, the larva sheds its skin and appears covered with fine-pointed hairs. Pupa.—Reddish-yellow, and apparently enclosed in a filmy trans- parent case. ‘Two bristles on the forehead. Imago.—Citron yellow, with downy hairs ; antennz blackish; eyes black ; legs pale yellow ; wings covered with strong hairs ; antennz of ¢ 3 length of body, 13-jointed, hairy; those of ¢ 14 times length of body, 25-jointed; thorax of ? gray ; abdomen has brown edges ; ovipositor can be extended to twice the length of the body, and is as thin as a hair; wingsof ¢ twice as long as abdomen. Length of 9 1°5 to 1:6 mm,; of ¢ o’9 to 1 mm. The ‘“‘ Wheat Midge” comes out in June and July, and has been seen in England as late as the 17th August. The 92 seems to fly about amongst the wheat stalks during the day, to begin laying eggs an hour or two before darkness begins, and to continue laying throughout the night. These ‘ Midges” are also found in grass along hedge sides and in clover.* There are probably two broods or more in one season. It attacks wheat and rye, and according to Wagner, barley and oats also. Some think that on first emerging it lays eggs on couch grass, and perhaps * Manual of Inj. Insects, p. 90,—E. A. Ormerod. ee ees se ee aan t. NEMATOCERA. 77 on other grasses, and that broods from these infest the wheat ; the reference above is certainly in favour of this theory. The ‘‘ Wheat Midge” is attacked by Platygaster tipule, which lays eggs within its eggs by means of a very long ovipositor, and by JZacroglenes pene- trans, which lays eggs within the larve. This insect was first recorded in England in 1776, then in North America, then in France, and later in Austria, Hungary, Germany and Prussia. Prevention and Remedies of Attack: Miss Ormerod says (in the work mentioned before): ‘‘ The best method for prevention of this ‘Red Maggot’ is to give it no winter shelter, which is zaturally at the roots of the corn crops or of couch grasses, and artificially in large chaff-heaps. The chaff-heaps and the rubbish and dust from the threshing machine can be easily managed, and in the fields a great deal of the ‘Red Maggot’ may be got rid of by special methods of ploughing, or by taking the cultivator through the land and collecting and burning the stubble roots.” In America various methods of ploughing in the stubble and top soil, and thus placing the ‘‘ Red Maggot ” under unfavourable condi- tions, are employed. But one of the most important points in pre- venting the spread of this pest is entirely doing away with those hot- houses of ‘‘ Wheat Midge,” namely, heaps of chaff and dust from the threshing machine, which are so often seen. Not only does this mode of heaping the chaff seem to hasten and favour development of the Midge, but it enables the breeding to take place more freely, for we know that very few ¢’s are found in the cornfields, and Miss Ormerod, from her observations, thinks that the pairing takes place amongst the countless number seen over these heaps ; if, then, these were burnt or placed in unfavourable conditions, such as in catile yards, much good might be done by not only retarding development of the ‘ Red Maggot,” but by stopping the further production of the species. Dr. Taschenberg recommends the destruction of couch grass near cornfields, as it harbours this fly to a large extent, and he further says: “The meadow foxtail grass is certainly at present open to suspicion of infestation.”* Griffiths? says destroy especially the wild oat grass (Avena fatwa), upon which the larvee of the wheat fly feed. D. Fraxinella, Meade. ) « =C. Minuta, Wtz.) Dr. Meade says this is probably the same as C. minuza, of \Vin- nertz. It seems to be intermediate between Diplosis and Cecidom ia. The Ash-cauliflower Gnat.” * Practische Insectenkunde, pt. iv., p. 16; also vzde American Goy. Repo. ts. + Diseases of Crops, chap. iv., p. 117. 78 AN ACCOUNT OF BRITISH FLIES. Lives as an ingulbine in the cauliflower ash gall.* It is a small yellowish-brown gnat with black head; palpi and proboscis pale yellow, a tuft of white hairs on the face. Thorax brownish-yellow, with three brownish-black longitudinal stripes nearly confluent on the g. Abdomen yellow, white hairs, base black. D. helianthemt, Hardy. The larvee live in the terminal leaves of HZ. vulgare, collecting them into bunches and stopping the growth. ‘They usually are found at the base of these amalgamated leaves, sometimes in great numbers. The larvee have a few hairs on each segment and several apical ones. The anchor process is dark testaceous. Length about one line. They appear in June and July. The zmago is very small and yellowish-brown ; the thorax is yellowish with brown markings ; eyes brown ; scutellum reddish-brown ; face, antennze and palpi yellowish ; the antennze are 14-jointed in the @. Wings moderate-sized, of a yellowish tinge, the veins slightly marked with bands having spots of an ash colour, the ends of the bands having seven ash-coloured spots on the edge. Halteres pale. This species has been described by Hardy in the Annals of Natural History, in 1880. D. buxt, Laboulb. { Zipula flava, Sch. \D. Schineri. The larvee live in blister-like galls on the leaf of Buxus sempervirens, and pupate in these inflated patches. Laboulbenet gives a good series of figures relating to this species. ZImago.—Yellowish ; metathorax reddish and of a rather rosy tint. On the back of prothorax are three bands, one median and two lateral, not well defined and slightly brownish. Wings in @? trans- parent and more opaque in the dg, veins yellowish in 9; hairy. Halteres yellow at base, red at the tips. Abdomen yellow, extremity deep orange in?, brown in ¢. Ovipositor brown. Feet yellowish ; thighs dark gray, black hairs. Tarsi yellow; first joint shortest ; second very long. The body is hairy. PI. ii. (7). D. botularia,} Wtz.— The Ash Midge.” = C6: jraximt. Br: In many parts of England, but especially in Kent and Surrey, the leaves of the ash in sheltered places are seen to turn yellow and fall off prematurely in July and August. They are known as “blighted ” leaves, a name which may mean anything. ‘These infected leaves * Ent. Mo. Mag., 1888, p. 23. + Ann. Ent. Soc., France, 1873, pp. 313-326, pl. ix., figs. 1 to 17. + Gard. Chron., Dec. 31, 1870.—Miiller. NEMATOCERA. 79 are distorted and crumbled ; with thickened mid-rib ; this is enlarged chiefly on the under surface of the leaf. The sides of the leaves are folded over, and they resemble a pod. These galls are pubescent. Each cell contains a single larva, reddish-yellow in colour. When the larvee require to fall to the earth to pupate, the galls, through lack of nutriment, split, and the larvee escape by this crack. Pupa skin silvery white ; three weeks in this state, Fig. 12 (6). Imago.—Reddish-yellow ; three pale brown streaks on thorax ; halteres white; abdomen brown, hind border fringed with white hairs. Legs brown, white pubescence. Wings grayish, violet irides- cence, veins brown. Antenne 26-jointed in ¢, 14-jointedin ?. D. linarie, Wtz. The larvee live in tufts formed on the tips of the buds of Zénaria vulgaris. ‘They pupate in the same place. The zmago is yellow ; the antennze brownish-yellow ; thorax brown, with three dark bands or stripes. Abdomen brownish-yellow; legs brown, yellowish white underneath. Wings covered by a light pubescence, veins yellowish. Halteres pale. Antenne of @ 26- jointed, very much longer than the body; in 9 the antennz are 14-jointed, shorter than body. ‘Third segment of oviduct white. ( Tipula pint, Deg. | Cecid. pint, Mg. PIT Den — , C. pini-maritime, Du. | C. pilosa, Bremi. es laterella, Zett. The larvee of fzvz have rows of fleshy setiferous caruncles along the back, with two setiferous tubercles on the last segment. They live on Lrnus sylvestris, This larva is figured by Perris, who evidently mistook the dorsal for the ventral surface, as was also done by Dufour. The cocoons are resinous structures on the pine-leaves. They appear to inhabit almost any species of pine. The zmago is dark brown to black ; antennze yellowish, palpi tawny ; sides of the thorax and abdomen reddish-brown, becoming brown after death. Wings pellucid, veins dark, halteres light gray. The antenne in the ¢ longer than the body. In the ? 13-jointed, about half the length of body, the joints four or five times the length of their petioles. Legs dusky, with white or silvery pubescence on the under surface. The whole insect may sometimes have a dirty white pubescence on it. The oviduct is short, with two small roundish valves, light brown to yellow; ¢ organs brown. 80 AN ACCOUNT OF BRITISH FILLES. D. callida, Wtz. The larvze live in the seed-capsules of various poppies, and are said to be found in company with Cecidomyia papaveris, according to Walker. Verrall, however, only considers Papaveris a reputed British species. The zmago of this “‘ Poppy Gnat” is tawny ; the thorax has three dark brown stripes, pectus shining; antennze brown, base yellow. Wings brown; veins also brown. ‘Transverse veinlet joining the first longitudinal beyond its middle. Legs brown, moderately long. In the ¢ the antenne are very long, nearly twice the length of the body, the double joints as long as their petioles. In ? antenne are shorter than the body ; joints and petioles of equal length. Oviduct short, and composed of two lamelle. The wings have dark violet markings, which are especially characterized by two rows and a pointed spot. D. centralis, Wtz. = Cec. annulipes, Mg. The life history of this gnat seems uncertain ; if it is the same as Cecidomyia annulipes of Meigen* it inhabits beech-trees, but the synonym seems doubtful. Centralis is described by Schiner as follows: ‘“ Reddish-yellow thorax, with three chestnut-brown streaks ; the hairs of the whole body pale reddish-yellow. Antenne brown, much shorter than body ; joints six times length of petioles, the end joint with bud-like protuberance, Legs whitish. Wings clear as glass, with three blue- violet cross rows and similar spcts ; fifth venation starting violet, bent down in a right angle to the hind margin ; the third joining the edge rather behind the wing-point.” I believe Meigen’s description of annulipes is the same as that given by Walker under Centralis, viz.: “ 9 tawny, Antenne brown, a little more than half the length of body ; joints six times the length of their petioles. Thorax with three chestnut-brown stripes. Pectus blackish. Wings limpid, with three brown bands; veins brown ; transverse veinlet situated before the middle of the sub-costal (first longitudinal vein), anal (third and fourth) and its second branch forming an almost right angle. Halteres white. Oviduct as long as the abdomen, with two somewhat rounded valves. Legs whitish, with black bands.” + * Syst. Beschr., vi., 1130, p. 268 2. Schiner evidently does not consider them the same species. t+ Walker, Ins. Brit., viii., p. 115. | . NEMATOCERA. 81 D. flava, Mg. = Cec. hilarella, Zett. The ¢ yellow; with black head. Antenne dark brown, 16-jointed, as long as the body ; joints never longer than their petioles, the latter yellow, the joints are alternately longer and shorter. Wings opal- escent ; veins faint and yellowish ; first longitudinal less than half length of wing; second longitudinal vein slightly curved ; second branch of anal (3.4) curved obliquely to the hind border. Halteres pale. Legs long and slender; pale yellow. Length x lin. The larvz live in rosettes on the stalks of corn. (Die Larve soll nach Roser I. c. in Getreidehalmen leben.) D. jacobe, Lw. The larvee live in the flower-heads of Senecio _Jacobea. Susp-GENus.—Hormomyzia, Lw. #7, Fagi, Hartig. This species, which is common all over Europe, is most abundant in Switzerland and in England. The galls in the former place seem to be of a pyramidal shape, in England they are horn-shaped ; both upon the upper surface of beech-leaves (Fagus sylvatica). According to some accounts the galls drop off and the larvze pupate in them. /mago.—Dorsum blackish-brown, with three narrow stripes ; abdo- men flesh-coloured, with gray hairs. Antenne of JQ 24-jointed, petiolate, of @ shorter and sessile. Wings brownish, with gray hairs, but appear white against a dark background ; base of second longi- tudinal vein hardly discernible ; third longitudinal bent in front in a rectangular manner, lower branch only visible at base, upper hardly discernible, the fold almost looking like a vein, 2-24 lin. (Hartig— Jahres-bericht, 1, p. 4, 641 (1839). Lupa, Fig. 5, Taf. i., vol. viii., Lin. Ent. Winnertz. a/fi, Figs. 22 and 23. Wang, Fig. 8, Taf. ii. Antenne, Fig. 9, a, b, c and d, Taf. iil. fT. capree, Wtz. = C. capree, Hardy. The larvee of this species live in pustule-shaped galls on the leaves of Salix caprea, aurita and oletfolia, and pupate under fallen leaves, according to Winnertz. The zmago is dark reddish-yellow, with three dark stripes on the dorsum, of which often only the middle one exists in fragments. Antenne shorter than body, 14-jointed, petiolate in ¢, sessile in 9. Wings large, whitish with grayish-white hairs ; second longitudinal vein ending in the extremity of the wing, its base very weak ; third longitudinal vein bending in front in the form of a bow; #? to 1 lin. 6 82 AN ACCOONT OF BIATISE LLIES. Ht. Pow, Bosc. = H. graminicola, Wtz. The larvee of this species form rough brown oval galls on Poa nemo- ralis, and pupate in these galls. d Whitish-yellow. Pectus and metathorax dark brown. Antenne grayish-brown, yellowish in places. Wings limpid; legs brown. Antenne, 19-20-jointed ; shorter than the body ; the joints are twice the length of petiole. The abdomen is dark brown, the sutures being lighter, sometimes yellow. ? Abdomen tawny ; the posterior borders of the segments have brown bands on them. Antennze, 19-jointed and half the length of body. Joints much longer than the petioles. Tip of oviduct ex- panded, no valves. fT, piligera, Lw. = annulipes, Hartig., Wtz. The hairy galls on the leaves of Fagus sylvatica are the home of the larvee of this “ gnat.” ¢ Dark brown; palpi yellowish-brown; antennze longer than body, joints longer than petioles ; dark brown. Sides of thorax and abdomen flesh-coloured. ? Antenne as long as head and thorax ; joints not petiolate. Ovi- duct long, yellow, no valves. The joints of the antenne are from 17 to 20 in number. ff, fasciata, Mg. ? Brown; antennze 14-jointed. Thorax yellowish-brown ; three dark brown stripes and a black spot on each side behind. Pectus dark brown. Abdomen yellowish-white, with a black shining band on the posterior margin of the first to seventh segment. PI. ii. (1). Hf. Ptarmice, Vallot= H. floricola, Wtz. One often notices the flowers of Achill@a Ptarmica deformed and stunted ; this is generally due to the attack of the larvee of this gnat, which live in the deformed flower-heads, ¢ Black ; dark pubescence ; antennz brown, 18-jointed. Antenne shorter than body, joints twice length of petioles. Sides of thorax brownish-red to pink. Wings broad and milky. Abdomen brownish- yellow. Legs dusky brown, silvery hairs beneath. ? Antenne only half length of body ; joints five to six times the length of their petioles. Abdomen flesh-coloured. Legs have white pubescence beneath. Oviduct elongated. Length 1 lin. I find this first mentioned in “ The Memoirs of the Academy of Science, Dijon,” for 18409. NEMATOCERA. 83 FT, millefolii, Uw. = C. achillee, Inchbald. The larvee inhabit calyx-shaped galls in the axils of the leaves of Achillea millefolium. Besides these there are four other British species, viz. : Ff, abrotantz, Traill. Fl. cornt, Gir., the larvz in galls on Cornus sanguinea. Vide Kalten- bach (18), p. 295. H!. Fischeri, Fefld., form swellings on the stems of Carex pilosa. Vide (18), p. 730. The _ larvee live in spindle. shaped galls on ° Tipula juniperina, Linneé. the upper twigs Cecid. 7 Deg. of the juniper, H. juniperina, 1. = Oligostropnus juniperina, Lat. }and metamor Lastoptera " Mg. |phose in the é ead flavimaculata, Zett. galise at ade Bremis (1); "1p: 24, and Schiner (7); P+ 399: Sup-GENUs.—Dirrhisa, Lw. Schiner unites Dirrhiza, Lw., with Lp7dosis, from which it only differs in this: that the transverse veinlet is plain, and the antenne in ? sessile, and in ¢ only short petioles. D. rhodophita, Hardy. This small sub-genus is represented in England by one species only, viz., D. rhodophila, described by Hardy.* Bergenstamm says, ‘‘Lebenweise unbekannt.” Found only in England; another species Zazerita is found in Europe, habits likewise unknown, 9 Jmago.—Pale; small; elegant; head black; thorax brown above, with three lines of “ griscous” hairs ; scutellum and meta- thorax yellow or pinkish; abdomen short, light yellow ; legs long and slender, yellowish. Wings wide, with purple iridescence, finely pubescent and fringed. Costal and first longitudinal vein distinct. Antenne black, 18-jointed ; first and second joints thick and cup- shaped, gradually getting smaller, last joint ovate, short verticillate hairs. Halteres white. Length $ lin. SuB-GrEnus.—£prdosts, Lw. Walker describes several of this sub-genus, but they are not now * Ann. of Nat. Hist., vi. 182 (Larvee possibly form galls on the rose). 6—2 84 AN ACCOUNT OF BRITISH FLIES. included in the British Fauna. The only true British species is Ee. longiges. Pl. 1. (3). £. longipes, Lw.* Low describes the 2, and Walker gives a good figure. Mr. Haliday took it in Tullamore Park, Ireland. The antennz are about twice the length of body, and 16-jointed in the ¢. Wings large, much longer than body. Legs long and slender. PI. 1. (3). £. defecta, Lw. This is a reputed British species. The larvee live in decaying beechwood. The imago is pale yellow, the extremities of pincers black. Antenne pale brown, 15-jointed, with whorls of very long hairs. The last joints of tarsi white. Wings long and narrow, with pale sray hairs and pale brown veins; slightly iridescent. Antenne of ? 13-jointed. Ovipositor long, no lamellae. Colours fade at death. SuB-GENus.—Asynapta, Lw. Of the sub-genus Asywapta, Taschenberg remarks that it may be divided into two groups. PI. 1. (4). First group (Asyzapta, Rondani), lengthened neck and large palpi, with four very long joints. Second group ( Winnertzia, Rond.), unlengthened scutum, smaller palpi, with four only moderately-lengthened joints. Asynapta luguéi-ris, Lw.t The larvee of this gnat live in decaying beechwood, according to Schiner. Taschenberg describes the 2 as piercing the budding ' leaves of the plum to lay her eggs therein, and the larvee as inhabiting lemon-shaped galls in June. They pupate in August. Jmago.—Scutum black-brown and shiny; sides dark yellow; abdomen yellow with whitish-gray hairs. Palpi very hairy. Antenne 14-jointed, joints double the length of petioles. Legs yellow. Wings blackish with dark hairs ; first longitudinal vein apparently distant from front edge ; second longitudinal vein rising steeply, finishing in the tip of the wing. Antennz in @ short ; ovipositor long, two long lamella. Parasites attacking this species: Preromalus piscipalpis and Lurytoma Amerlingt. * Vide Low (2) D.B., 1850, iv., p. 35. ft Ins. Brit., vol. iii., p. 129. NEMATOCERA. 8s Winnertsia tenella, W\k. This seems only to have been described by Walker,* and is re- corded from England. Walker describes the zmago as being testaceous, with black antenne. Wings limpid, being narrow towards the base; veins testaceous ; first longitudinal vein about } length of wing; second longitudinal vein curved towards the tip of the wing, parallel to the border, ending near the tip ; first branch of third longitudinal obso- lete ; second curved abruptly and slightly obliquely to the border. Antenne in ¢ 16-jointed, in ? 12-jointed. Oviduct short. Life history unknown. Sus-GENus.— 4 sphondylia, Lw. Four species of the sub-genus are recorded in England. Walker describes several others, but they are not considered authentic. A. sarothamnt, Lw. The larvee live in galls produced on the twigs of Sarothamnus scorparius. The galls are small bud-like structures, and in these the metamorphosis takes place. The perfect insect is dark gray, with tawny head, scutellum, pectus and metathorax. Wings brownish ; antennze 15-jointed in g, r4-jointed in ¢. The ovipositor is brownish-yellow and very long in this species. ‘The oviduct, pupa and palpus have been figured by Winnertz.t This species is much smaller than U/7ic’s, and the ovipositor much longer. PI. ii. (8). A. ulteis, Traill. dg and @ brownish-black, paler on the breast, sides and bases of humerus ; face and palpi yellowish; abdomen shining-brown, sides paler ; antennz 13-jointed, not so long as body ; the joints following the two basal ones decrease in length until the last two, which are stout and form a knot. MHalteres and legs yellowish, varying to brown ; coxz grayish. 4 genitalia yellow, ¢ orange. ‘l’ransverse veinlet indistinct ; wings iridescent, hairy. The larva form galls resembling flower buds, but larger on Ulex Europeus. ‘he galls are lined by a gray pubescence, on which the larvee feed A. geniste, Lw.t The larvee form green galls on Genista Germanica, and meta- morphose there. This species is larger than the above. * Vide Schiner, Die Fliegen, vol. i1., p. 406. + Lin. Ent. Tom. 8, Taf. 1, figs. 6, 15 and 20. 2 VadevAnna Ents.soc. Pr; 1370) p..L7/7- 86 AN ACCOUNT OF BRITISH PLIES. A. pimpinelle, F . The larvee live in galls on Pimpinelle saxifraga. ‘They pupate in the earth. ; SECTION 2.—LESTREMIN A. SuB-GENus.—Campylomyza, Mg. The life histories of this sub-genus are not well known—many live in decayed wood. ‘They are common insects in hedges, woods and windows, especially those of hot-houses. Pl. 1. (6). C. flavipes, Mg.=C. pallipes, Zett.* Black, shining, with brown abdomen. Wings limpid, nerves dark , halteres pale ; legs testaceous ; length } lin. Found amongst grass in the autumn. C. bicolor, Mg. Very like the former. Black; fuscous abdomen ; wings limpid ; distance between tip of first longitudinal vein and transverse veinlet is four times the length of the latter; halteres whitish ; legs pale ; length $ lin. Appears in the autumn. Cc. aceris, Mg. Shining black ; abdomen piceous ; wings limpid ; halteres, veins of wings and legs testaceous. Length # lin. C. halteraia, Zett: — C. aira, Wik. Black, piceous legs and abdomen. Halteres white ;+ wings limpid, gray, dark pubescence; length 1 lin. Habits unknown. Pie i.“(6). : A fossil, Campylomyza (C. grandeva), has been found in the Purbeck beds of the Dorsetshire Coast. Susp-GENus.—Micromyia, Rud. M. globifera, Hal. = Campylomyza globifera, Wik. et Hal? Imago.—Deep black, not glossy. Antenne not so long as the thorax, r1-jointed, fuscous ; first two joints black; second joint very large in g. Wings white, hyaline ; costal and two anterior veins light brown, posterior veins colourless; halteres and legs dingy yellow— abdomen long ; posterior segments in 9 not so much attenuated as usual; eighth and ninth largely exserted, dingy yellow; terminal “ Diptrscane, volix., p. 3072. + According to Walker they are piceous. NEMATOCERA. 87 tentacles more dusky, 2-jointed; second joint smaller, orbiculate ; beneath them a compressed obtuse process nearly as long ; forceps of ¢@ unguiculate. Found on short grass at Holywood, etc. (Haliday) ; length ¢ ? lin. 9 2 lin. PI. ii. (3). SuB-GENus.— Catocha, Hal. C. latipes, Hal. = Macrostyla latipes, Wtz. Black, head small, round; eyes lunate; ocelli three, unequal ; abdomen eight segments ; dirty brownish-yellow, with dark incisions ; antenne in ¢ 16-jointed ; 10-jointed in 9, shorter than in 2, joints oval, except three and ten, which are elongated ; antennz brown, dark brown at the base ; thorax shining, oval, convex ; scutellum large, semilunate ; wings broad, obtuse, pubescent, broad fringe on posterior border. The first longitudinal vein ends at about half- length of wing, second longitudinal ending hardly in front of tip of wing ; cross vein small; third longitudinal forked ; fourth and fifth simple ending at the border ; halteres brown ; legs brownish-yellow ; last two or three tarsal joints dilated, one pulvillus (Fig. 6). When alive the zmago is metallic-blue, with brick-red appearance under the wings. This colouring soon fades in death. Bergenstamm says ‘* Lebensweise unbekannt.” PI. 1. (5). SuB-GENus.— Lestremtia. This sub-genus is interesting as connecting the Cecidomyidze with the Mycetophilide. ‘The veins of the wing resemble Sczava, while the antenne and legs are truly Cecid in character. PI. i. (7). “Sciara leucophea, Mg. Tipula juniperina, Fab. | Chironomus juniperina, Fab. EB cinerea, Macq. L. leucophea, Mg. = This species is found in larch groves; the habits are unknown. Antenne of ¢ 15-16-jointed. Scutum brown above, yellow at sides. Abdomen dirty brownish-yellow. Legs pale yellow; tarsi dark. Antennz brownish ; long petioles. Wings transparent ; small hairs, with brown veins. First and second longitudinal veins parallel and near each other ; second longitudinal ending far from the extremity of wing ; fork of fourth longitudinal vein very long ; that of third longitudinal still longer ; upper tooth straight ; under tooth bending towards posterior edge. 38 AN ACCOUNT OF BRITISH PLES. L. carnea, H. Lw.= Cectdogona carnea. This species has white halteres ; antennz black. Wings with pale veins ; black near costa. Abdomen of ¥ testaceous, also legs (in both sexes); tarsi brown. Habits and metamorphosis likewise unknown. PI. ii. (9). A third species is recorded in Verrall’s list as British, viz., Z. cénerea, Meg., and also described in Walker and Blanchard.* Bergenstamm and Low say it is synonymous with Z. deucophea, Mg. GENus.—Lasioptera. The insects in this genus are distinct from the ones we have been discussing. ‘There are three longitudinal veins, although this is not easily seen at first; the first being very faint and running with the second close to the costa. Pl. i. (10). The wings are short and broad. Antennz 16-26-jointed ; the joints are sessile and sub-globular. Proboscis very short. They are small and delicate insects. Ocelli absent. Eyes lunate. ‘Tarsi very long ; metatarsus often very short. In their habits they resemble the Cectdomyzda, infesting plants much in the same way. The larve are much the same as in the Cecids, having the same peculiar reddish hue and curious “ breast- bone.” Clinorhyncha is considered by some as a sub-genus of Laszoptera, by others as a distinct genus, the chief difference from Laszoptera being the prolongation of the mouth into a rostrum. This sub-genus is not recorded from England, however. There only appear to be two verified British species of Laszoptera ; three others recorded in Verrall’s list seem to be doubtful, and there are also two reputed forms. . L. picta, Mg. L. rubi, Schrk. et Heeger.t =+ L. argyrosticta, Mg. L. fusca, Vallot. The larvee live in excrescences on the stems of various Audz and metamorphose in the galls. They appear in May. Lmago.—Brownish-black ; antennze of ¢ black, shorter than the head, 20-21-jointed. Palpi yellow; head yellow and_ brown. Thorax deep black ; “schildchen” white. Abdomen and ¢ genitalia covered by white hairs. Legs also covered by silvery hairs. Wings clear ; costa thick and dark, in the middle a white spot, root of costa * Histoire Naturelle des [nsectes, iii., 1840, p. 574. + Lin. Ent., vol. viii., p. 306., pl. iv., figs. 11 and 14. NEMATOCERA. 89 so pale. @ resembles ¢, only the antennez are 21-22-jointed. Ovipositor yellowish-white; long; no lamellz. After death the colours turn browner and the white hairs less silvery. PI. i. (2). L. albipennis, Mg. The larvz live between the scales of the galls produced by C. rosarta on Salix alba. Lmago.—Deep black ; wings limpid and hairy, gray at the tips, with veins and cilia black; a small white spot is present at the tip of the first longitudinal vein, on the costa. Legs piceous, stout moderately long.* L. stygia, Mg. This is a brownish species, yellowish on the ventral surface ; black antennz ; densely pubescent dark-gray wings. Legs long and stout, white in certain lights. Metatarsus longer than any of the following joints. Life history unknown. L. obfuscata, Mg. = Cecidomyia obfuscata, Walker (p. 86). Testaceous ; black head and antenne. Thorax brownish. Legs as in species above, but with brown bands on the tibiz and tarsi. Walker says the larvee have been observed by Kaltenbach to feed on the thistle. L. fuliginosa, Steph. Habits unknown. Recorded in Stephen’s “ Illustrations of British Entomology,” 1846 (p. 42, Fig. 4). L. pusilla, Mg., and derberina, Schrk., are two reputed species in the English fauna. The family just passed over in this chapter is seen to be one of great importance, on account of its containing so many insects that are injurious to plant life, especially two (C. destructor and D. tritici) ; many of the others are injurious in a less extent. Considering, then, the destruction caused by these small and insignificant-looking flies, it is strange that they have passed unnoticed so much in England ; scarcely any local lists contain more than one or two species out of the great number already recorded in Britain. Dale, for instance, only records C. ¢ritic’ from W. Cornwall; only three or four are * Sys. Besch. der b.e.z., Insekten, A. 1818, T. i., p. 89, pl. iii., fig. 5. go AN ACCOUNT OF BRIGTSE FILIES. mentioned in the list of Diptera found at Hastings, etc. Yet with a little trouble a great many may be captured. I have taken as many as ten different species myself on the windows of a single room on one wet afternoon. With careful collecting a large number may be met with, and many new species to the English fauna are sure to be captured. Verrall gives a long list of reputed species, none of which have been dealt with here ; many of these are recorded and described in Walker’s “ Diptera Insecta Britannica,” but until further evidence is found they will be left out of the British list ; by degrees, no doubt, they will all find their way back again, but at the present rate it will take many years. Amongst those who have done most for this family must be mentioned Winnertz, whose ‘‘ Monographie der Gall- mucken ” in the Linnzea Entomologica is of so much value. Other works of importance on this family are quoted below : Literature on the Cecidomyide : 1. Beitrage zu einer Monographie der Gallmiicken. Denkschr. allg. sch. Ges. f. d. ges. Nat. Neuenburg, T. ix., 1847. —Bremi. 2. Dipterologische Beitrige, 1850. Posen, T. iv.—Low. 3. Ueber den Bernstein und die Bernstein fauna.—Low. 4. Ueber die Entwicklung der Cecidomyienlarve aus dem Pseu- dovum. Archiv. f. Nat., 1865, T. xv.—Mecznikoff. 5. Systematische Beschreibung der bekannten Europiischen zweifliigeligen Insekten. Aachen, 1818-1838.—Meigen. 6. Monograph of Diptera of North America.—Osten-Sacken. 7. Fauna Austriaca, Diptera.—Schiner (Wien, 1864, T. ii.). 8. Practische Inseckten-Kunde. Leipzig.—Taschenberg. g. Insecta Britannica Diptera, vol. iii.—Walker. 10. Linnzea Entomologica, 1853, T. viii Winnertz. tr, Beschreibung einiger neuen Gattungen aus der Ordnung der Zweifliigler. Stett. ent. Zeitg., 1846, T. vii. 12. Dipterologisches, z/d., 1852, T. xiil. 13. Synopsis Cecidomyidarum. Vorgelegt in der Versammlung, v. 5, Jan., 1876.—Bergenstamm und Low. 14. Hist. Nat. des Insectes Dipteres. Paris, 1834.—-Macquart. 15. Naturgeschichte der Insecten, 1834.— Bouché. 16. Fauna Boica. Landshut, 1803, T. 11i1.—Schrank. 17. Beitrage zur Kenntniss der Insectenlarven. Stett. ent. Zeitg., 1847, T. vill.—Bouché. 18. Die Pflanzenfeinde aus der Klasse der Insekten. Stuttgart, 1874. fo nN NEMATOCERA. 91 9. The “ Hessian Fly” and ‘‘ Wheat Midge.”—Miss Ormerod : Reports. . Die Pflanzengallen Norddeutschlands und ihre Erzeuger.— Rudow, 1875. . Ueber die Gallen und andere durch Insekten hervorgebrachte Pflanzendendeformationen. Stett. ent. Zeitg., 1861, T. xxil., p. 405.—O. Sacken. British Entomology, 1872.—Curtis. CHAP TE Ra, TALE MY CERO PH 1 igieD A OR ‘“* FUNGUS GNATS.” THE JAlycetophilide are a large family of gnats related to the Cecidomyide, and formerly contained two genera (Catocha and Les- tremia), which are now placed in the latter family, although both these genera show affinities to the Sctarina. The following names are synonymous with the family— (Mycetophiline et Sciarine, Zett. | Mycetophitites, Newman. | Zip. Mycetophitides, Westwood. \ Tip. Fungicole, Mg. On the one hand we see the family is closely connected to the Cecidomyide by Lestremia, etc., and on the other to the Aidionide by the genus Azarete, which was for a long time retained in the family we are dealing with now. Besides these two connections there are also close affinities to the ‘“ Fleas,”* as exemplified by the genus Mycetophila, and, according to Walker, especially by the species M. nigra, a northern species, but from the description of it given by Zetterstedt in his “Insecta Lapponica” (p. 860), I fail to see any resemblance unless in the appearance of the legs, but even there it is very slight. These “fungus gnats” also appear to be connected to the Tipulide through the genus Dzxa, which for a long time has been hovering from family to family, and at last has been satisfactorily disposed of by raising it to a family of its own in the neighbourhood of the Ptychopteride. In many respects the problematical ava resembled the genus Bolitophila. t was included in the family under consideration by Meigen and Zetterstedt, but is now definitely separated from it. At present the JZycetophilide seem to be little understood, My cetophitida = - * Walker’s Ins. Brit., viii., p. 6. THE MVCELOPHILEIDAL. 93 although some good work has been done recently on the Continent, especially in Russia. Verrall has not worked this family yet, so the British list is far from complete ; nevertheless, forty genera and about 160 species are recorded, and many reputed. Many of the species described by Walker must be eradicated, as in all the other families, with the exception of the Dolichopodide. Few insects are more abundant than the “fungus gnat,” but their appearance is so extremely erratic that one may go a whole year and find none, then hundreds may suddenly appear. They seem to have been first discovered in the Purbeckian Period, and many genera have been obtained from these Mesozoic beds, including Platyura, Sciophila and Macrocera (vide Brodie’s ‘ Fossil Insects”), from the lower Purbecks of Wilts and Hants. From the Solenhofen States Germar* describes a Sctava, S. prisca, and one also by Giebel.t+ The three genera figured by Brodie are given by Giebel as new genera, viz., Adonia, Sama, and Thimna respectively. Besides these Westwood also figures an obscure species referred to the extinct genus Zhiras. When we come to the Tertiary Period we find large numbers of these ‘‘ gnats,” which are represented by the genera Zygoneura, Mycetophila, Leta, Sctara, Sciophila, Sciobia, Platyura, Macrocera, Heterotricha, Dianepsia, Mycetobia, Aclada, Diadocidia, Boletophila, Cordyla, Brachypeza, Trichonta, Boletina, Gnoriste,t and an extinct genus Sackenza; more than 280 species have been found, and from widely separate areas, mostly from the ambers of the Continent and from America, the rock species being few compared to the amber. Their range in “me is seen to be fairly wide, as also is their distri- bution in space, for the fungus gnats appear in most parts of the globe, from Scandinavia into the tropics. They pass into the Arctic circle, cold seeming to have no influence on them. For some time I kept the pupz of some A/yee/ophilide in a temperature of 30°, the effects of the cold only retarding the development a few days, and in no ways injuring the species. In England several species may be taken in the middle of winter. The habitat of the imagos is generally amongst the grass and in hothouses, where they may sometimes be taken in great numbers on the glass. They also often appear in great numbers on windows in houses, and I have noticed this especially during the autumn. One of the most notable points in the habits of these gnats is the peculiar * Germar, ‘ Nova Acta,’ Ac. of Leo. Ch. of Austria, 1839, xix. 2, S, 189-222. + Fauna der Vorwelt. Giebel. + Edin. New Phil. Journal, 1829, pl. vi., figs. 8, 9. 94 AN ACCOUNT OF BRITISH FLIES. method of leaping, resembling the “hop” of a flea, the hind legs being adapted to this use. When found out of doors, many (Mycetophila) may be taken in damp ground, and others in plenty near and around fungi, especially when they are somewhat decayed. Many are (Sctophila) short lived; others (AZycefophila) hibernate, and appear in the early spring, and according to Heeger, “ copulate after a few days, generally in the evening. After six or ten days the female, if the weather is moist and rainy, lays its eggs on the funzi growing on old horse-chestnuts, singly, twenty or thirty on the same fungus. ‘The larvee hatch after eight or ten days.” The “fungus gnats” have not been studied in the same way the Cecids have, and our knowledge of them is not very satisfactory. Recently some good work has been done on the Continent, especially in Russia, by Dziedzicki, whose ‘‘ Monograph of European Phroniw”* is of great value. The small size and the absence of damage done by the larvee has hindered their study in such detail as has been done in the Cecidomyidz. Some few are certainly injurious, as the species that live upon the ‘“‘ Mushroom,” whole frames of this edible fungus being destroyed by these larvae; but the amount of damage done is small compared to the amount of good which these maggots do in destroying fungi. The @ lays her eggs generally on the under surface of the pileus (AZycetophila), walking about over the surface first to find a suitable place, then depositing the ova singly. Others (.Sczara) lay their eggs in decaying vegetable matter; they may, as in some of this genus (Sczara) be laid in long strings. The eggs are white and cylindrical, and vary from 4 to } of a line in length. ' The larve hatch after eight or ten days. ‘The account of the larvee is mainly taken from a paper kindly sent me by C. R. Osten- Sacken,t which gives a concise and full description of the structure and habits of AZycetophila larvee. In this paper he gives the follow- ing characters of the larv: ‘“A distinct horny head; a fleshy labrum, encased in a horny frame ; horny flat lamelliform mandibles, indented on the inside ; maxillee with a large coriaceous inner lobe, and a horny outside piece, with a circular excision at the tip; labrum horny, small and almost rudimentary ; body fleshy, with eight pairs of stigmata.” The antenne are mostly rudimentary (JZycetophila, Sciara) and spring from a pit on each side of the mouth; they are often only “fleshy swellings,” but in some (Ao/itophila) they are distinctly * Tor. Ent. Rossland, xxiii. 7+ Characters of the larvee of AZvetophilide. | THE MYCETOPHILIDA. 95 jointed ; in this the first joint is fleshy, and divided into two by a horny ring; second joint cylindrical and horny; third joint short, often bearing a bristle. Fic. 13.—Mouth parts of AZyeetzd larva.—a. Labrum ; 8. Maxilla; y. Mandible = a 6. Labium. Ocelli may be present, and are figured by Osten-Sacken in his paper as a small, pellucid convex spot below the antenne in A/ycefophila larvee. The mouth parts of the larvee are typical and normal, consisting of labrum, mandibles, maxille, and upper lp. The dabrum, Fig. 13 («), is fleshy and encased in a horny frame ; its function, according to Osten-Sacken, ‘‘seems to be, principally, to shut the oral orifice, and perhaps to press on the mandibles and maxille: during the process of mastication.” The maxille, Fig. 13 (8), are horny and serrated on the inside. The maxille consist of two pieces: a triangular cardinal piece («) and a s#ixps composed of two distinct pieces, an inner and outer (@) and (a); the inner one has a serrated lobe on the inside, showing much analogy of structure in all the larvae (Scéara has six or seven indentations, Mycefophi/a ten or eleven). A rudimentary fa/pus ts present in some forms (.Sciophz/a) ; it is 2-jointed. In other genera it is very rudimentary. The upper lip, Fig. 13 (6), little developed. Usually as a V-shaped, horny piece between the maxilla. This may have some function in connection with the cocoon spinning of the larvee. The Mandibles, Fig. 13 (y), are horny lamels serrated on the inside, and are compressed between labrum and maxille. The general form of the body is sub-cylindrical, elongated, and fleshy, white or yellowish, and composed of twelve segments. In many it is serpentiform (Scéophila), some stout (Lolitophila). Vne skin is smooth ; hairs on the ventral surface. Eight pairs of stigmata are present: one pair on the first thoracic and seven on the first seven abdominal segments. The larve are generally transparent, 96 AN ACCOUNT OF BRITISH FLIES. the alimentary canal being plainly seen through the integuments. On the ventral surface organs of locomotion seem to be represented by slight swellings armed with bristles. Fic. 14.—A. Larva of Sczophila ; B. Larva of Ceroplatus ; Cc. of Sctara. The habits of the larve are interesting. They are all gregarious. They all, with the exception of Sara, seem to live in fungi. Sciara prefers vegetable mould and under the bark of trees for its home. The larvae, according to various observations, appear to moult several times before they pupate. The Sczophila larvee do not live zuszde fungi, but seem to prefer to crawl about on the outer surface, on the under side of the pileus, which they cover with threads. This web- formation is a very common feature in the larvee of this family ; a coarse webbing is formed over the surface or under side of the pileus, and in and under this the larve live. The larve forms a slimy tract where it crawls along. Perhaps the most interesting are those of Sciara, known as the “ Army Worm.”* They differ from other Mycetid larvee by the absence of any bristles on the ventral surface, by the structure of their trophi and by their habits, nearly all living in large numbers under the bark of trees and in mould. At certain times these larvae seem to migrate, for what purpose we do not know. They form columns twelve to fourteen feet in length, two or three inches broad and half an inch thick, containing countless numbers as close together as they can be packed. These processions are often seen in woods on the Continent, but what they are for or what they mean we cannot tell ; as the larvee are always full grown it cannot be for feeding purposes. It is this habit that has given them the name of “ Army Worms.” Some larvee of this family are noted for a * Heer-wurm is a better term, as so many larvee which are gregarious are called <¢ Army Worms.” ee THE MYCETOPHILID. 97 curious structure formed of their own excrements, and carried on their backs, one such structure, resembling an Azcy/us-shell. This has been observed by Perris in the larvee of J/ycetophila scatophora, and by Brauer in a species from Brazil. The larvee, as a rule, spin a cocoon, but this is not always the case. Aolitophila, according to Dufour, has no cocoon; neither have certain A/ycetophile. Others (Sciara fuscipes) have an earthy cocoon. ‘The general rule, however, is that some kind of case is formed for the pupz, which are found, as a rule, in fungi.* Some species of Scéara are also met with in cow-dung. Zhe pupa (Fig. 15) is smooth, the angles being rounded ; not sharp, as in the Tipulide. (The pupz of Sczara are somewhat different, and strongly resemble those of the Cec¢domyza.) ‘The larval skin is not retained in this stage, as is done in many cases. The legs are applied to the breast and venter; the antennz bent round the eyes, and their remaining portion between the legs and wings. In Fic. 15.—Pupa of Sczara. Sciara they may be expanded into a tooth at the base. In the same genus the prothoracic stigmata is placed on an elevation, which may extend into a horn. An air-tube may be seen entering it. Stigmata on abdomen plainly marked. There are certain interesting points about the !arvee of JZyceto- philide. One, is their curious habit of congregating into large bodies for migration; the other the brilliant luminous nature of certain larvee in this family. The former we shall deal with when we go more fully into the genus Scara, whilst now we will look at the remarkable phenomenen of luminosity shown by certain species in- cluded here. The cases of larvee emitting a brilliant light are few in the Diptera. This phosphorescent character has been observed in * Mr. Dale tells me ‘‘some larvee spin a web on the outside of a fungus, and turn into pupze somewhat after the manner of the small Eggar Moth (A. danestris).”” This would be probably in the genus Sczophi/a. 7 ors) AN ACCOUNT OF BRITISH FLIES. the larvee of Chironomus by Osten-Sacken, * in Culex by Pallas,+ as long ago as 1782, and also in the larvee of Zipula oleracea by Main.t These are the only records of any importance I can find. But in the AZycetophilide this phosphorescent character has been more fully observed. It was first noticed by Wahlberg,§ who, whilst studying the transformations of Ceroplatus sesioides, saw a bright light emitted by the larva and pupa, but not by the perfect insect. More recently some interesting papers have appeared in the Lxtomologist’s Monthly Magazine\| by Hudson and Osten-Sacken. These luminous larve, described by Hudson, came from New Zealand. According to one of the best authorities, Osten-Sacken, they were the larve of Scophila, certainly those of one of the J/ycetophilide. The vividness of the light produced is best described in Mr. Hudson’s own words: ‘‘ The light from a single individual kept in a caterpillar cage may be seen streaming out of the ventilators at a distance of several feet.” He describes it as coming from a gelatinous knob at the posterior ex- tremity of the larva. Those who are interested in phosphorescent insects should read ‘‘ Les Insectes Phosphorescents,” Henri Gadeau de Kerville. Rouen, 1887. Internal Anatomy of Ceroplatus§ and Mycetophila. The alimentary canal has two salivary glands opening into its proximal end, close to the mouth. Each gland is a slender, single tube, one on each side of the canal. In AZjcetophila these glands are composed of large secreting cells with a dark nucleus. The duct of the gland is very fine, and is a simple tubular structure, the cells being more regular and clearer than those of the glandular part. The mouth opens into an asofhagus, which is short in Ceroplatus, but of moderate length in JZycetophila. The crop is oblong, with simple walls and with a small tubular neck in Cevop/afus. In the Mycetophila 1 examined there seemed only a slight constriction between the cesophagus and crop. The Chylific ventricle is long and cylindrical, and commences from two lateral conical, sack-like ceeca. These two czeca I was unable to find in the flies -I examined, but Dufour found them in Cerop/atus. There are four Aepatic ceca, which open into the base of the chylific ventricle. The zxéest7ne is small and the walls appear to be smooth, ending in a somewhat * Ent. Mo. Mag., 1878, xv., p- 43. + Kleine Notizen in den neuen Nordischen Beitragen, 1782, t. iv., p. 396. + Mag. Nat. Hist., 1837, p. 549. § Act. Holm., 1838, and Stett. Ent. Zeit., 1849 (trans.). || Ant. Mo. Mag., vol. xxili., pp. 99, 133-230. “| Dufour, Anns. des. Sc. Nat. T. xi., 1839, pp. 193-213, pl. 5. LHE MVCETOPHILID A: 99 swollen part—the vectwm. I failed to find any traces of J/a/phigian tubules in Mycetophile. The Wervous System is composed of nine ganglia. Dufour says they are distributed as follows: ovze in head, two in thorax, and six in abdomen. In the mycetid I examined this was certainly not the case. There are certainly ¢wo cerebral ganglia, two thoracic, and only five in the abdomen. This is the normal number for the /wzg7- cole. \Vhether Cerof/atus is abnormal in having ten, or whether Dufour miscalculated the cerebral ganglia I have not been able to make out, as I have not had any live Cerof/adi to examine. The Respiratory System.—Vhere are eight pairs of stigmata, two thoracic and six abdominal, from which proceed delicate trachez. I have been unable to make out their distribution. The 9? sexual organs are composed of two long and rugose glandular ovaries, opening into a long neck and passing into an oviduct, which can be extended by the 9. Internal Anatomy of Larve. The mouth parts of the larva consist of the following parts: A fleshy labrum in a horny frame; a pair of horny, serrated mandibles ; a pair of maxilla and an upper lip (Fig. 14). Dufour, in his descrip- tion of Cerop/atus, figures two large eyes in the larva. These are wrongly described, they only being the bases of the antennz. Into the mouth open ¢wo salivary glands ; these are long, tubular struc- tures, often as long as the body; but in one species I examined (Sctophila ?) they were not so long. The walls of the glands seem tc be simple. No doubt these have some function in the web- spinning of the larvz, and possibly manufacture the fluid that forms the thread for the web as well as a fluid for digestive purposes. I failed, however, to find any difference in the structure of the cells that would justify this conclusion. ‘The wsophagus is narrow, but soon passes into a large crop with corrugated walls, somewhat in- flated. The crop is preceded by a small, almost globular tract, which I take to be the fpvoventricu/us. Into the base of this open four ceca, which are evidently the same as the proventricular caeca of the tipulid larva. Dufour in his Cerof/atus larva only figures two of these long ceca. The stomach is large, and its walls are much folded. Into its base, or distal extremity, open the /epatic ceca. I was unable to make much of these in the Mvcetophila larve I examined. There are certainly four czeca, but whether they united into a single pair before entering the stomach, as shown in the figure of Ceroplatus, or entered as four separate tubes, as is usually the Ue 100 AN ACCOUNT OF BRITISH FLIES. case, I was unable to settle. The stomach passes into a sma// intestine, which somewhat suddenly becomes inflated, the latter part being the /arge intestine. ‘The intestine is coiled several times, one of the chief features of the whole alimentary tract being its great elongation and also the same of its glands. ‘The body cavity being densely packed with adzpose tissue. Fic. 16.—Alimentary Canal of Mycetid larva (Mycetophila).—a, cesophagus ; 6, crop; c, proventriculus; d@, salivary glands ; e, stomach ; /, small intestine ; g, large intestine ; 4, cecal appendages (4 ?); z, hepatic czeca. The Nervous System is composed of eight ganglia in ALycetophila, six in the body and two cerebral ganglia in the cerebral mass; viz., a supra- and infra-cesophageal united by a thin tract on each side. Fic. 17.—a, head of an Astndiulum ; b, antenna of Aszvdileum (hairs too long) ; c, head of a Sciara. Characters of the Family (Imago). Body elongated and compressed, often bare ; head small; eyes round or oval, ocelli present two or three in number, unequal in size; palpi q-jointed, cylindrical, the first joint very small. LE MM CERO RTILLD Ze. IOI Antenne 1o-16-jointed, porrect and simple; pronotum small ; scutum of meso-thorax undivided : wings and halteres present except in Zpidapus ; the discal areolet wanting, veins few ; abdomen, seven segments, rarely eight ; legs formed for leaping ; coxe large ; tips of tibiz armed with large spurs ; bristly hairs are developed on the legs, which are not, however, macrochetz.* Fic. 18.—Boletina dubia. Classification of Mycetophiiide. The family is now divided into eight sub-families, which are given below in tabular form : A. Middle transverse vein elongated. a. Brachial vein wanting. 1. Diadocidine. ©. Brachial vein present. I. Antennz not very long. a. Brachial vein long. 2. Mycetobine. aa. Brachial vein short. Ceroplatine. II, Antennz very long. 6, Antennze setiform. 4. LBolitophiline. (oS) om -& 66. Antenne filiform. . Macrocerine. b. Middle transverse vein not elongated. a, Brachial vein present, legs long. 6. Scophiling. 8. Brachial vein wanting. 7. Mycetophiline. * The Nematocera are characterized by the total absence of macrochetz. The stouter hairs on the thorax and scutellum of Cz/ex and on the legs of the AZyceto- philide, Osten-Sacken tells us, ‘can hardly be considered as such” (An Essay of Comp. Cheetotaxy, Tr. Ent. Soc., Lond., 1884, Pt. 4). Continuing, he tells us “The Culicida, Chironomide and Tipulidz are distinguished by the development and sexual differentiation of the antennz, which are in this case very probably the organs of orientation. The same conclusion may be arrived at with regard to the Cecidomyidz and ALycetophilide.” The difference, however, between the bristly hairs on the legs of ‘* Fungus Gnats” and the typical macrochetz of the Muscide seems to be very slight. On the legs of certain AZycetophilide and Cecidomyiade 1 have found curious club-shaped hairs ; what their function is I do not know. Mr. Dale thinks they are probably to assist them in leaping. 102 AN ACCOUNT OF BRITISH FLIES. y (i). Joints of antennz cylindrical, petio- late or non-petiolate. (ii). Joints of antenne in d oval, petioles long; in 9 sessile and cylindrical. 8. Sciarine. The following are the characters of the more important genera found in Britain : Sub-family Scaring.” y (i.) 1 Wing longer than body; surface minutely hairy; joints of an- tennze hairy. Te SSCLOTa. y (1.) 2. Wing small, shorter than abdomen ; surface minutely hairy. y (1.) 3. Wings and halteres absent. y (ii.) 4. Wing much the same as Sciara, but the fork longer; basal branch wavy, and upper branch vaulted. 4. Zygoneura. bo Lradysta. Epidapus. i) Sub-family AZvcetophiline.t A. Three ocelli on the front. I. Abdomen with seven segments. a. Proboscis not elongated. 6. Costal extending beyond tip of cubitus. c. Basal part of cubital vein and middle transverse vein equally long. d. Auxiliary vein extending to costal. Anaclinia. cc. Basal part of cubital vein longer than the middle transverse vein. d. Base of fourth hind areolet under base of cubital vein. Leptomorphus. dd. Base of fourth hind areolet nearer base of wing than is the base of second hind areolet. Boletina. 46. Costal vein not extending beyond the tip of the cubitus. Glaphyroptera. aa. Proboscis elongated. Gnoriste. * Beitrag zu einer Monog. der Sciarinen. Winnertz. Wien., 1867. + The classifications of the following families is also according to Winnertz. Verh. Zool. Bot. Geo., 1863.) ITEC MMC LO PELMELIDA, II. Abdomen with six segments. a. Hind vein forked. 6. Fork short. 66, Fork long. aa. Hind vein not forked. 6. Middle discoidal forked. 66. Middle discoidal not forked. B. Three ocelli: one on the inner border of each eye; third in the middle of the fore front. a. Costal vein extending much beyond the tip of the cubital vein. c. Two ocelli: one on the inner border of each eye. The third either in a pit and scarcely noticeable or absent. a. Base of fourth hind areolet nearly in a transverse line with that of the second hind areolet. 6. Base of fourth hind areolet much more distant from base of wing than is the base of second hind areolet. . Base of fourth hind areolet much nearer to the base of wing than is the base of the second hind areolet. 6. Petiole of second hind areolet long. 6b. Petiole of second hind areolet short. aaa. No fourth hind areolet. b. Fore cubital areolet moderately broad. 6b. Fore cubital areolet very narrow. c. Hind vein not forked. a. Base of fourth hind areolet in a trans verse line with that of the second. aa. Base of fourth hind areolet more dis- tant from base of wing than is base of the second hind areolet. 6. Costal extending a little beyond the cubital. c. Costal not extending beyond tip of cubital. a. Base of fourth hind areolet a little nearer base of wing than is the base of second hind areolet. _ Celosta. Leta. Acnemua. Azana. Mycetophila. Dynatosoma. Cordyla. Exechta. Mycothera. Zygomyta. Sceptonia. Decesia. Anatella. Phronia. 104 AN ACCOUNT OF BRITISH FLIES. b. Petiole of second hind areolet very short. 66. Petiole of second hind areolet long. aa. Base of fourth hind areolet much nearer to base of wing than is the base of second hind areolet. 6. Costal ends a little before tip of wing. Sub-family Scophiline. A. Costal vein extending to tip of wing. B. Costal not extending to tip of wing. a. Base of fourth hind areolet much nearer base of wing than is base of second hind areolet. 6. Base of fourth hind areolet a little nearer to base of wing than is base of second hind areolet. a. Second hind areolet with very long petiole. aa. Second hind areolet with moderately long petiole. c. Base of fourth hind areolet in a transverse line with the base of the second, or very near the base of the wing. ad. Base of the fourth hind areolet much more distant from the base of the wing than is the base of the second hind areolet. Sub-family Ceratopline. A. Mouth elongated, like a beak. B. Mouth not elongated like a beak. a. Antenne dilated ; palpi not bent to- gether. 6. Antenne not dilated; palpi bent to- gether. Sub-family AZycetobine. A. Brachial vein and cubital forming a sessile fork. Leymosta. Allodia. Brachycampta. Sciophila. LEmpheria. P olylipta. LEmpatta. Tetragoneura. Lastosoma. Asindulum. Ceratoplatus. Platyura. Mycetobia. THE MYVCETOPMILIDA, 105 B. Brachial vein and cubital forming a petio- late fork. a. Base of this fork is nearer to the base of wing than is base of second hind areolet. Ditomyta. 6. Base of this fork is more distant from base of wing than is base of second hind areolet. Plesiastina. The other three British sub-families only contain a single genus. The above synopsis is compiled from Winnertz, whose knowledge of the Mycetophilide is unequalled, although, as we shall see, very much has recently been done in Russia, especially by Dziedzicki. Before ending the general account and classification of the fungus gnats, one word for their preservation. If, as mentioned in a former page, they do a certain amount of damage to mushrooms, the amount done is small compared with the benefits derived from their exist- ence. The larve of these gnats act as “scavengers”; not only do they do away with rotting fungi, but they cause these often injurious productions to putrefy and to become scarce by their destruction. I have seen large fungi on chestnut trees that were gradually increasing in number, until one of nature’s balancers came to the fore. The fungi, the first year of the attack of these Mycetid larva, decayed sooner than usual, and after that year they gradually decreased, until now scarcely any are to be found. ‘This work was done, then, by these larve, which were abundant in most of the fungi, and from which I bred several species of Mycetids ; had the production of the fungi continued at their rate of increase the trees must certainly have suffered. We now pass on to the more detailed part of the subject, and commence with the sub-family Scavina, Chironomus, F. flistea, ¥. Molobrus, Macq. Lat. | Tipula, Lin. GENUs.—Sciara, Mg. = - The members of this genus are small, and generally dark in colour, elongated and attenuated posteriorly. The antenne are porrect, 16-jointed, and have a few short hairs on each joint, the two basal joints devoid of hair. Five longitudinal nerves to the wings, the third forked and branching from the second about one-third from the base; wings longer than abdomen. Palpi curved downwards, 3 or 4- jointed. Proboscis large in proportion to the head ; the labium is a 106 AN ACCOUNT OF BRITISH PLIES. bilobed structure. Ocelli present, three in number, one much smaller than the other two. Eyes large, emarginate. No transverse sutures onthe thorax. Haltereslong. Abdomen elongated, seven segments. Legs slender, and slightly elongated ; tibiz armed with two spurs. Their habitat is in grass, flowers, fruit and fungi.* The larve, which are cylindrical and shining white, live under the bark of de- caying trees, also in fungi and Aoée/i, and, according to Walker, in putrescent galls. Zetterstedt} says ‘ sub-cortice arborum hybernant,” but this does not always appear to be the case, as they sometimes hibernate in hay and straw. The pupze have two divergent caudal sete, and remain under the bark of trees and in the fungi; a cocoon may Or may not be spun. In some respects the larvae resemble Mycetophila \arve, but they have no bristles or spines on the locomotive processes on the venter, as in the AZycetophile. One of the most remarkable characters of the larve of this family is their gregarious and migratory character. From the latter the name of “Army Worm,” or in Germany ‘“ Heerwurm,” has arisen. At certain times of the year large companies of this Aeerwurvm migrate in a long procession, sometimes as much as 14 feet in length, and 2 or 3 inches wide, and may be # inch thick. This dense layer of larvee must contain some millions of individuals, sticking close together and crawling over and over one another. The processions of the “Army Worm” are seen in Germany, Sweden, Russia and America. What this migration is for, still seems doubtful; the larve usually being full fed, it would not be for change of feeding ground. But Beling,} in a recent paper, comes to the conclusion that this is the object of the march. This latter view seems most natural were not the larvee full fed. It was usually believed that the larvee forming these masses were those of S. Thome, but Beling tells us they are those of .S. mzltaris ; in one case only did the larve belong to a different species. The “Army Worm” has also been made known in America by Cope,§ who has published his observations on the appearance of this worm in Pennsylvania ; and from this author’s paper the following notes are taken: The rate of advance about four inches in five minutes, the hinder ones working their way over the top of the rest, the whole mass thus taking up in the rear and laying down in the * A singular habit in this genus is that of two ¢’s frequently copulating with the same 2. Mr. Dale has more than once seen them flying in that position. t LZusecta Lapponica, p. 825. ~ Der Heerwurm (Zeit. f. die. ges. Naturw. v. 46, 1883, pp. 253-271). § Proc. Ac, Nat. Sc. Philad., 1867, p. 222. F THE MVCETOPHILIDE. 107 front. They are said to resemble a thin gray snake when migrating in this manner ; and he records the attack on these bodies by ants and coleopterous larvee when on the march. Berthold* says ‘‘ the Heerwurm can be regarded as a collection of larvae, for the purpose of mutual transformation : that is, it is accomplished through mutual protection at a period favourable to development. ‘This connection is given up before the formation of nymphs arrives.” Another feature of interest in Sc/ara larvee is the possible produc- tion of galls by S. ¢/¢co/a, as described by Winnertz, but Professor Mik and Osten-Sacken seem inclined to doubt this. Of course it is possible that the Sczava larvee live as zzguzlines in the galls produced by some Cecid. Fic. 19.—The three types of venation in Sczava. This genus has three well-defined types of wings, and is divided into three distinct groups by the following characters : (2) The second longitudinal joins the costal deyond the fork of the fourth longitudinal. (6) The second longitudinal vein joins costal a¢ the level of fork. (c) The second longitudinal vein joins costal defore the fork. (.S. lateralis, Mg. Tipula Thome, Lin. and Schrk. Flistea Thome, F. iron Thome, Lat. Salhome, lh. —- This species has a black shining thorax. Abdomen fuscous ; the ?has a yellowish band on each side. Antennze black, short, smaller in? than ing. Wings almost black, and shiny ; the second longitudinal vein extending much beyond the fork of the fourth, and more than half length of wing. Legs short and moderately stout, femora testaceous, coxee and tarsi dark brown. ‘The abdomen and thorax have dark brown hairs. This species, which is common, appears in the summer and * Nachrichten Uniy. Gottingen, 1854, p. I. 108 AN ACCOUNT OF BRITISH FLIES. autumn in woods and thickets. The larve are known to congregate in large numbers, and may possibly abroad form the so-called ‘‘ Heer- wurm ” in some instances. ‘This is the largest of the genus. It does not hibernate. S. carbonaria, Mg. This insect is almost black all over. The thorax is shining ; antennz a little longer than head and thorax ; wings hairy, shining brown in @, darker inthe 2. Costa faint ; second longitudinal vein dark brown. The abdomen of the ¢ is longer and slenderer than in the 2, and the wings with shorter hairs. Legs testaceous ; tarsi dusky brown. Found in the spring and summer; rare in England, but not so on the Continent. Winnertz* says: “Ich habe sie Laufig auf Weiden bliiten augetroffen, und auch in copulo sefangen.” f flistea forcipata, F. S. florilega, Mg. ls. lugubris, Wz. (?) This species is black, shining. Wings blackish, darkest along the costa; halteres piceous at base, knobs black. Second longitudinal vein ending much beyond the fork of the fourth, and much beyond half the length of the wing. Abdomen in ¢ slightly hairy, in the 2 with a yellow line on the sides when alive, this disappears at death. Legs piceous ; tips of femora in ¢ testaceous, dusky in the ?. Dalet records this from West Cornwall, and it is mentioned as being common in Walker. Verrall places it amongst the reputed species for some reason. Loew} obtained the larve from the stalks of Aretiums§ Se HOTLO, he — 1 S. guinguelineata, Macq. This is a species mentioned by Curtis,|| and was reared from rotten potatoes. The zmago is black, with shiny thorax, with five whitish lines ; wings nearly transparent; abdomen blackish-brown. Legs dark black ; ends of coxz and femora testaceous, tarsi dark. Antenne yellowish. S. pracox, Mg. = S. fascipes, Mg. 9. Black ; thorax black and somewhat shiny ; palpi black ; antennz * Mon. der. Sciarinen, 1867, Wien., p. 14. + Diptera of West Cornwall, 1890-91. { Dip. Beitrage, fasc. 4th, p. 18, 1850. § This is probably the same species as carbonaria. || Curtis, ‘* Farm Insects,” p. 460, 1860. SS —<—- THE MV CELOPHTEL DAL. Log short and stout in ¢ and in 9. Wings brownish; veins dark ; second longitudinal vein ending just before fork of third longitudinal vein ; fourth longitudinal vein distinct. Abdomen fuscous ; halteres piceous ; legs short and stout ; dark. Found in May on and about the Bilberry ; generally abundant. Heeger* gives the following account of the habits of this species : “The females lay their eggs in decaying fungi or vegetable mould. The eggs are in short strings, from six to ten in a row. If the weather is favourable and the temperature moderate the larvee are excluded in eight or ten days. They shed their skin three times, at irregular intervals, depending on the conditions of heat and moisture. Before undergoing the pupa-state they form near the surface of the soil a little barrel-shaped case, out of which the pupa extricates itself in part before the exclusion of the perfect insect. ‘The shedding of the skin and transformation generally take place in the morning ; copulation more frequently in the evening.” S. pulicaria, Mg. This has been reared from putrescent galls and, according to Curtis,t from rotten potatoes. It is found in the autumn about gardens and on windows. The zmago is black; thorax shining black, with abdomen dark blackish brown. Wings glassy ; costal nerves dark ; the remainder pale ; fourth longitudinal vein pale before its fork ; second longitudinal vein ending much before the fork of the fourth. Halteres brownish, with black knobs. Legs testaceous ; tarsi blackish. S. flavipes, Panzer. In this gnat the thorax is testaceous, with a small pale band on the humeral region. Abdomen dark above, yellowish on ventral surface. Palpi black and testaceous. Antenne black ; testaceous at the base; longer in ¢ than 2. Coxz yellowish-brown ; tarsi brown ; wings nearly limpid ; veins light brown ; fourth longitudinal vein pale before the fork ; second longitudinal vein extending to half length of body; not up to the fork of fourth. The fly appears in summer amongst bushes and underwood, and is fairly common. S. hyalipennis, Mg. This is another plentiful species found in gardens and hedges about the end of May and June. * Beitrage, etc., Sitzb. d. Wien. Ac. xi., p. 27, T. ii. + Curtis, ‘‘ Farm Insects,” p. 460, 1860. 110 AN ACCOUNT OF BRITISH FLIES. The perfect insect has a brown thorax with four black stripes. The abdomen is dark brown, almost black. Antennz brown. Wing nearly limpid (sab Ayalinis), with the veins dark. The second longi- tudinal vein extends to the fork of the fourth longitudinal vein. ‘The latter is indistinct before the fork. Halteres brownish. Legs tes- taceous or yellowish ; tarsi brown, or even black. Meigen obtained this species from flower-pots.* 5 pallizes, F = ! Tipula pallipes, F. Chironomus pallipes, ¥. Black ; thorax slightly shiny ; ventral surface yellowish. Antenne slender, }-length of body. Wings limpid ; veins dark-brown. Second longitudinal vein extending to fork of fourth longitudinal vein before joining the costa, more than half the length of wing. Fourth longitudinal vein pale before the fork. Legs yellowish ; tarsi dark. Walker says this species is common, but Verrall evidently doubis its authenticity, it being in italics in his list. The life-history appears to be unknown. S. tilicola, Lw. This fungus gnat is supposed by Loew to form a gall on the leaves of young linden trees. Winnertz first discovered this curious habit, and noticed that the galls were present on the leaves in shady and sheltered situations: “The /emon-yellow larve, capable of leaping, like cheese maggots, lives in numbers in the stem, generally near the origin of the last or two last leaves. Each of them has a hollow of its own, and produces a swelling of the size of a pea, which it abandons before its transformations.”+ Osten-Sacken and Professor Mik do not believe this account. They consider the galls are formed by some Cecid, and that the Z7/co/a larve are only “ inqui- lines” in the galls. It is most probable that the galls are the same as those described by Walker as produced by Cecédomyia tilie on the young shoots growing from lime-trees. He says: “ They (the galls) are round or oblong; more than twenty cells, each inhabited by one larva. The latter is about one line of length, and of a dright yellow colour, and has the faculty of /eafing, like the larva of Prophila.” The zmago of Tilicola is dusky, with somewhat shiny thoray. Antenne slender, yellowish. Wings nearly limpid, with costal nerves brown ; the remainder pale. Legs dusky yellow; tarsi dark, with somewhat yellowish bases. * Eur. Zweif, 1., p. 233. + Character of larvze of Mycetophilidz, Osten-Sacken, p. 17. LAE MN CE LO PEL ETD A. 101 S. Ruficauda, Mg. This is slightly smaller than 7Zome, and can easily be distinguished from it by its red abdomen. Dale has taken it from rotting hay and straw in the autumn. There are a large number of this genus found in England. Win- nertz, in his ‘‘ Monograph of the Sciarinze,” describes 175 species, and those who wish for detailed descriptions, and who intend work- ing at this group, should consult it. As it seems a somewhat rare work in England I append his method of classifying this genus of the Mycetids : I. The second long. vein (unterrandader) joins the costa at or beyond the fork of the fourth long. vein. (Fig. 19, A, B.) A. Wings black or brown. 1. Antenne black or brown. A. payee veinlet situated défore the middle of the second long. vein. . The apex of the cubitus (second long. vein) lies nearer to the apex of the wing, than does the apex of the lower prong of the fork. $8. The apex of the cubitus (second long. vein) and that of the lower prong are equidistant from the apex of the wing. . The apex of the lower prong of fork is nearer the apex of wing than the apex of the cubitus. The transverse veinlet is situated 27 the middle of the second long. vein. a, B. and y. as above. c. The transverse veinlet is situated beyond the middle of the second long. vein. a. Only. B. pee yellow. . Antenne black or brown. ‘f Transverse veinlet situated Jefore the middle of the second long. vein. a. and £. B. iy gape veinlet situated zz the middle of the second long. vein. Only. 2: Antenne sia A. Transverse veinlet situated before the middle of the second long. vein. 6B. Only. II. The second long. vein joins the costa before the fork of the fourth long. vein (Fig. 19, c c.) AG Wes black or brown. . Antenne black or brown. A. @, , y, as above. B. a, (3, as above. Cc. a, B, y, as above. 2. Antenne yellow. = y, as above. a, B, y, as above. B. Wi ings yellow. . Antenne black or brown. . aas above. - aas above. . a, B, as above. . Antenne yellow. . a as above. . a, B, y, as above. . a, B, y, as above. AOBrFNAAD Ss 112 AN ACCOUNT OF BRITISH FLIES. The British species of this genus tabulate as below : A. Second long. vein extends beyond fork of fourth long. vein. Wings dark brown or black Sides of abdomen yellowish Thome. Sides of abdomen black Morio (2) Sides of abdomen black Carbonaria. Abdomen red Ruficauda. Wings gray Legs testaceous, thorax with three cinereous stripes Avznnzfes. Legs testaceous, thorax black, shiny Nitidicoll?s. Wings nearly limpid, abdomen elongated Caudata. AA. Second long. vein extends to the fork of the fourth long. vein. Piceous, cinereous stripes on thorax Hyalipennt Black, veins dark Pallipes. Black, veins pale Trlicola. AAA, Second long. vein not extending to fork of fourth long. vein. Halteres brown or black Wings brown Pr@cox. Wings gray Fuscipennts. Wings limpid Fourth and fifth veins dark Large Vitripennts. Small Minima. Fourth and fifth veins light Second long. vein ending at about half length of wing Scatopsotd.s Second long. vein shorter, not half length of wing Fenestrata. Halteres testaceous, with black on knobs Piceous, thorax with gray stripes Fucata. Black, thorax black Pulicaria. Halteres testaceous or white Body black or brown Fourth and fifth long. veins dark Longipes. Fourth and fifth long. veins pale Body slender Halteres testaceous Aprilina. Halteres whitish Pusilla, Body very slender Gracilts. Body tawny Flavifpes. Body testaceous Slender : tarsi black Pallida. Very slender: tarsi brown Compressa. Nore.—Quinguelineata is not given by Verrall as a true British species ; five white lines on the thorax distinguish it at once. GEnus.—Braadysia, Wtz. This is a genus founded by Winnertz, and contains only three species. It is distinguished by the shape, etc., of the wings. The characters of the wings are as follows: Shorter than the abdomen, narrow, minutely hairy, with “ da/d mehr bald weniger keit formiger Basis” (Fig. 20). There is only one British species mentioned in the list, viz. : B. brevipennis, Wik. ' nase be Ens, ue . angustipennis, Wtz. (?) LAE MV CERO LDA, 113 This species is testaceous, with black head and antennz. Wings very short and narrow. Hind borders of the abdominal segments blackish. Tarsi brown. Fic. 20.—Wing of Bradysia. Walker describes this from a specimen in the British Museum. It seems to agree closely with Angustipennis, described in detail ( ? ) by Winnertz, and this author says concerning this point: ‘‘ Die Identitat derselben mit Scéara brevipennis, Walk, ist nicht unwahr- scheinlich.” Dale has taken this under stones in company with ants. Genus. —Zfpidapus, Hal= Chionea, Curtis. Thorax much compressed behind, so as to seem conical from above. Wings and halteres wholly obsolete. Abdomen incrassate in the middle ; tip attenuated, decurved, furnished with the ordinary two linear obtuse pubescent and free valves of the ovipositor. Fic. 21.—Epidapus venaticus. £. venaticus, Hal. Thorax black ; abdomen piceous, hairy; palpi yellow; antennz shorter than body ; legs testaceous ; lamellz of ovipositor round. The larvz live in the rotten wood of Carpinus betulus. GENUS.—Z) goneura, Mg. Osten-Sacken places the genus in the Cecidomyidz on account of the following characters: (1) the coxe being far less elongated, and the spurs of the tibize far shorter than in other genera of the AZycero- philide ; (2) antennz moniliform with verticillate hairs, seen in Cecids, but never in ‘‘ Fungus Gnats.” The same author continues 8 114 AN ACCOUNT OF BRITISH FLIES. to state that “the total habitus of the Zygoneure being more like that of the former (Cecidomyide) than of the latter (AZycetophilide), and the tibial spurs being so very short, that in some species they can only be discovered by the closest scrutiny, I think I may be justified if I add them to the Ceczdomyide, though in many respects they agree with the genus Sc¢ara, which has its place amongst the Myceto- philidz.”* But in other characters it approaches very closely to Sciara, and so it is placed amongst the MZycetophilide. No doubt it is a transitional form between the two families, and I see no reason why it should be placed one side of the line more than another ; but as it is so placed by Brauer, and as this work follows his classifica- tion, it is placed in the present family. Fic. 22.—Wing of Zygoneura. The characters of the genus are as follows: Ocelli present, three in number. Labium bilobed. Palpi 3-jointed, curved downwards. Antenne 16-jointed: in ¢ verticillate and pedicelled joints; in 9 pubescent, joints sessile. Thorax elliptical. Branches of fourth longitudinal vein very arcuate at the base. MHalteres long. ‘Tibial spurs small or absent. One species is recorded in England, and is somewhat scarce. Z. sciarina, Mg. Black, shining thorax. First part of the fourth longitudinal vein pale; rest of veins black. Halteres testaceous. Palpi yellow. Antenne in ¢ as long as body; in @ shorter than body. Legs yellow ; tarsi dark. Found in summer and autumn in underwoods. At the next genus we enter the second section, viz., the JZyce/o- philine. GENuSs.— Cordyla, Mg. = Pachypalpus, Macq., Zett. The characters of this genus are as follows: Body narrow. Ocelli two, small, contiguous to the eyes. Palpi thick at base, short. An- tenne incrassated, short and thick. Number of joints vary in sexes and species, and also in form. Wingsrather short. Abdomen some- what compressed and slender. Legs short; tibiz armed with longish spurs. The veins of the wings resemble JZycetophila. ‘The larve also are said to resemble those of AZycetophila, one C. crassipalpa, Macq., has been figured and described (larva and pupa) by Dufour.t * Dip. N. America, pt. i., p. 7. t+ Ann. des Sc. Nat., 2e series V., xii. and xiii. (pp. 5-60 and 148-163). THE MYCETOPHILID. 115 They live upon fungi. There are possibly four or five British species. C. brevicornis, Staeg. = C. valida, Wik. This seems to be a rare species, and is described in Walker under the name of Valida. Recorded from Glanvilles-Wootton and the New Forest. The zago is yellowish, stout, and compact. Lanceolate antennz shorter than thorax ; joints short. Wings grayish and stout. Veins tawny. Legs are stout, with longish spurs ; brown tarsi; hind tibize armed by very minute spines. ‘The second longitudinal vein ends at before two-thirds of length of wing. Sub-anal (fifth longitudinal vein) being forked and nearer base of wing than the fork of the sub-apical (fourth longitudinal vein). Length 2 lin. C. flaviceps, Staeg. Head yellowish. Thorax tawny or yellowish in front, also sides, and under surface. Antennz and palpi yellow. Wings having the fork of the fifth longitudinal vein much further than the fork of the fourth longitudinal vein from the base of wing. Legs tawny, short, and thick, long spurs ; tarsi dark ; posterior tibize with minute spines. Length 1 lin. GEeNus.—Mycetophila, Mg. This is an important genus, of which eleven species are recorded from Great Britain and twelve more are reputed; whilst Walker describes about fifty. The characters of the genus are as follows: Body generally small, elongated, and hairy. The head is sessile and transversely broadened ; round in outline. Eyes are far apart and oval. Ocelli two in number. Proboscis short. The palpi 4-jointed (Meigen* only figures three joints; the first joint being very small, was evidently overlooked). ‘The three joints are nearly equal. Antennz 16-jointed ; not more than half length of body; filiform to cylin- drical ; setaceous ; very thick in some species. The thorax very convex and generally oval; metathorax small and sloping down to level of the abdomen, which is of seven segments, and compressed, especially in the @ ; in the ¢ it is more cylindrical. ‘The wings are often spotted and of moderate length and breadth ; the second longitudinal is straight, and ends just before three-quarters of length; the third longitudinal vein emitting the sub- apical * «Sys. Besch. d. b. Eur. Zwei. Insecten,” t. 2, tab. 9, fig. 17 (1820). S—2 116 AN ACCOONT OF BRITISH FLIES. (fourth) a little before middle of wing. It forms an angle with the transverse veinlet, and then passes straight to the margin, a little in front of the tip of the wing. The sub-apical (fourth longitudinal vein) is forked. The remaining vein—the sub-anal (fifth longitudinal vein)—is forked in some; in others simple. Anal (sixth longitudinal vein) does not reach margin, and varies in length. There is also a small veinlet (humeral) near the base of wing. ase of fourth hind areolet nearly in a transverse line with that of the second hind areolet. WLegs slender; coxze long ; the four hind tibize spinose, with two long spurs; only one spur on fore tibize and spines scanty. Tarsi longer in fore legs than hind. The curious formation of the legs, which are adapted to their hopping and skipping move- ments, are very characteristic, and resemble the legs of Pudex. The larve of this genus have been mentioned in the general account, and so we can now pass on to some of the species found in this genus. The genus, as taken by Walker, included about fifty-one species; but the old genus JZycetophila is usually divided into several distinct genera or, more correctly, sub-genera, The differ- ences between JZycetophila and Rymosia and FExechia are, for instance, very slight, and although they are separated off as distinct genera, in my opinion the characters are not sufficiently marked to justify them being raised to that position. Fic. 23.—Mycetophila cingulum,* Mg. XM. striata, Wik. M. semicincta, Mg. M, tat = ES SE aa be cunctans, Wied. M. rufa, Macq. This is a large and common species (24 lin. long, 4-5 lin. alar). The general colour tawny. There are three large reddish spots on * MW. cingulum, Mg. Thisisa testaceous species, with tawny abdomen. Wings also tawny in front, marked as in Fig. 23. Notverycommon. Length 14 to2 lin. THE MYCETOPHAILIDA. E17 the thorax; the middle one placed before the two lateral ones. Pectus testaceous. There are also ferruginous bands on the abdo- men. The wings are marked with a tawny hue. The veinlets of the pree-brachial areolet forming a right angle, the fore one about half the length of the hind one, and nearly as long as the fourth longitudinal before its fork. The fork of fifth nearer base of wing than fork of the fourth longitudinal vein. Tarsi are brown; legs tawny ; tibicze covered with long stout spurs ; fore tibize longer than fore metatarsi. . M. stolida, W\k. This species is described* as being blackish-brown. The antennze are tawny at the base and no longer than the thorax. Palpi tawny. Thorax clothed with pale down ; tawny in front, on each side, and beneath. Wings gray; transverse veinlets of the prze-brachial areolet slightly clouded with brown; veinlets of the pree-brachial areolet forming an obtuse angle, the hind one longer than the fore one and twice the length of the fourth longitudinal vein before its fork ; fork of fifth longitudinal vein further than fork of fourth from the base of wing. Halteres testaceous. Legs tawny, short and stout. ‘Tarsi blackish ; hind femora with black tips ; fore tibize longer than fore metatarsi. M. signata, Mg.= M. distigma. } fo) } The life-history of this species seems to be roughly known. Stanniust reared it from Boletus edulis, found especially in pine- woods. The larvze, according to Osten-Sacken, spin their cocoons without leaving the fungi. The cocoon is truncated at one end, and this truncature covered with a delicate web, which the fly breaks through in escaping. The larvee, as in all of this genus, are yellowish-white and stout, the horny head being brown. The zmago is yellow to rusty yellow; the thorax with three distinct and dark- brown longitudinal stripes, the middle one expanded in front; sides of the thorax sometimes brown. Abdomen variable in colour ; yellow, the anterior segments marked with brown, and divided into two spots by a line down the middle ; the sixth segment and ¢ organs tawny. Head yellow and brownish in parts; antennze brown ; yellow at the base. Legs tawny yellow ; hind femora brown ; tarsi brownish. Wings yellowish; tawny veins; a brownish spot on = Sins.) Britsj., vols iis, ps Ss + Bemerkungen iiber einige Arten Zweiflugl. Gattungen. Macrocera etc. Isis, 1830. 118 AN ACCOUNT OF BRITISH FLIES. the tip of the pree-brachial areolet and another near the costa. Length, 14 to 2 lin. MM. lunata, Mg. The metamorphosis of the species has been well followed by Heeger, but in his paper are many curious and erroneous state- ments, as seen in the following quotations: ‘‘ The stigmata are nine, on nine consecutive segments of the body, except the two first ;” and another more important point, viz., ‘The locomotive swellings and their bristles are described on the éack of the larva,” etc., etc. The eggs are + lin. long, cylindrical and white. The /arve are stout white maggots, with a dark-brown corneous head. ‘The eggs may be laid by the 9 singly or in patches (twenty to thirty) on the same fungus. The larve hatch after eight or ten days, and com- mence to burrow into the under side of the pileus. They shed their skin three times, and transform near the outer margin. Haliday says: “The larvee spins for its transformation a long pouch of silk (white), with a flat circular lid.” The pupal state lasts nine to twelve days, the fly generally coming out in the morning. The perfect insects and pupze hibernate, and appear in the spring. Bremi obtained it from Agaricus citrinus, and Haliday also records the larvee as living gregariously in the hollow stalks of Agarics. M. bimaculata, ¥. = ELE ELL EN ‘ LZ. pictula, Mg. This is a somewhat rare species in England. It is brownish- black and covered with pale yellowish hairs. Head blackish-brown. Palpi yellowish. Antenne blackish-brown ; yellowish at the base. Thorax with a yellowish stripe on each side, which is largest and broadest in front. Abdomen blackish-brown; ¢ genitalia brown ; ? with blackish-brown lamellae. Wings with a brown spot, which passes from the costa to the pree-brachial areolet, and at three- quarters of length with a gray band, which is brown in front. Tips of wings gray. The veinlets of the pree-brachial areolet form an obtuse angle. The fifth longitudinal vein forked beyond the fork of the fourth longitudinal vein. Halteres brownish-yellow. Legs tes- taceous; tarsi brown. Length, 13 to 2 lin. This is a large species, with alar expansion of 4-5 lin. THE MYCETOPHILIDEA. I1g M. ruficollis, Macq. MM. lurida, Mg. MM. monostigma. M. centralts. M. lineola, Mg. = This is more common and smaller than the above species. ‘The general appearance is dark brown, but the head is tawny. The palpi yellowish-red, and the antennze tawny at the base. There is a tawny stripe on each side of the thorax, as in dzmaculata. The wings are gray, and there is a brown spot on the tip of the pree-brachial areolet and of the fork of the fourth longitudinal vein. ‘The veinlets of the pree-brachial areolets form nearly a right angle. The abdomen is brown, with tawny bands on the hind borders of the segments, and having a white tomentum underneath. The ¢ genitalia yellowish- brown; ovipositor (2) yellowish. Legs testaceous; tarsi darker than tibize ; the latter armed with many stout spines. Length, 1} to 2% lin. M. lutescens, Zett. = MZ. Senata, Steph. Somewhat like cmgu/um, but as large, or larger, than punctata. Occurs from Glanvilles-Wootton to N. Scotland. GENuS.—Lymosia, Wtz. Three ocelli, one near each eye and the third in front ; very small. The costal does not extend beyond tip of the cubital. The base of fourth hind areolet a little nearer base of wing than is base of the second hind areolet, zez¢h the petiole of the latter very short. Legs long and slender. Metamorphosis unknown. _ {M. rufa, Macq. la domestica, Mg. Winnertz says the larve live in Agaricus melleus. The perfect insect is black to reddish-brown. Vertex with white tomentum. Head dull yellow to brown; proboscis and palpi yellow ; antennz brown; base yellow. Antennz twice the length of thorax in the ¢; about the same length as thorax in the 9. Pectus and sides of the thorax yellowish-red. Wings having the pree-brachial areolet closed by two veinlets, which form an acute angle, the hind one longer than the fourth longitudinal vein before its fork. Anal vein very short. Abdomen club-shaped ;_blackish-brown ; testaceous beneath ; with testaceous bands for half the length from the base ; the base testaceous in the 9; browninthe ¢. The ovi- positor is composed of three angular valves; the lamella thin and oval. The colour varies in the male. The legs testaceous ; spurs R. fenestralis, Mg. 120 AN ACCOUNT OF BRITISH FLIES. short; tarsi brown; tibie dark; very short spurs in hind ones. Length, 24 to 3 lin. Rk. maculosa, Zett. R. Jasciata, Mg. = {2 aiscoidea, Zett. MM. sonata, Steph. This is a common species, reddish-yellow in appearance, with testaceous ventral surface. The palpi and antennz are testaceous ; the latter dark at the base. The two veinlets, which form the prze- brachial areolet, make a right angle; the posterior one very much larger than the fore one; about three times the length of the fourth longitudinal vein before its fork ; the hind branch curved. The anal vein extends far beyond fork of fourth longitudinal vein. The abdo- men is brownish-black, with four testaceous bands on the fore segments ; the extremity of the abdomen is testaceous. The legs are long and slender, dark reddish-brown ; tarsi almost black; spurs long; very small on hind tibiz; the fore tibiz much shorter than fore metatarsi. Length, 14 to 2 lin. There are four other British species of this genus ; viz., truncata, Wtz.; maculosa, Mg.; selecta, W\k.; and sericea, Mg. Genus.—Dynatosoma, Wtz. = Mycetophila, Mg. This genus much resembles Mycetophila. There are two ocelli only. Zhe base of the fourth hind areolet ts much more distant from the base of the wing than ts the base of the second hind areolet. D. fuscicornis, Mg. = (MZ, fuscicornis, Mg. (MZ. preusta, Staeg. This is the only species of this genus found in Britain. It was formerly included in the Mycetophile, and was described as one by Walker ; but it is now raised to a distinct genus by Winnertz. The zmago is blackish-brown ; thorax tawny in front, with three dark-brown spots; palpi yellowish. Antennze yellowish at the base ; abdomen with a white tomentum beneath; legs yellowish; tarsi brownish; tips of posterior femora dark-brown; fore-tibize long. Wings grayish-brown, with two distinct brown spots, one on the tip of the pree-brachial areolet and of the fork of the fourth longitudinal vein, the other near the costa; fifth longitudinal vein forked; sixth does not extend to the fork of the fifth. Length 1} to 2 lin. Found in the autumn and winter. Genus.—Lixechia = Mycetophila, Mg. The ocelli two, small. Sides of the thorax with bristles. Abdomen THE MYCETOPHILIDA. 121 club-shaped, flattened at the sides. Wings somewhat short. Base of fourth hind areolet much nearer the base of wing than is base of the second hind areolet. Petiole of second hind areolet long. Fourth longitudinal vein short. Larvee live in fungi. £. fungorum, Dg.= M. fusca, Latr., Mg. This is a fairly common species. The larvee living in the pileus of 4oletus and other fungi. Imago dark-brown. Head brown, palpi and antennz yellowish- red; the latter dark-brown at the tip, very slender, and about the length of thorax. Thorax brown, tawny on each side; with grayish and small black hairs on parts. Abdomen blackish-brown, with tawny extremity. Pincers small and tawny. Wings with a brownish tinge; the veinlets of the pree-brachial areolet forming a slightly obtuse angle, the hind one much longer than the fore one, and about four times as long as the sub-apical vein before its fork. The anal (sixth longitudinal vein) does not extend as far as the fork of the fifth longitudinal vein. Legs pale yellow, slender ; tarsi brown; hind tibiz with minute spines and very long spurs. Length 2 to 24 lin. (MZ. guttiventris, Mg. E. lateralis, Mg. = \IL. seriata, Zett. This is another fairly common British species. It is dark brown, with testaceous ventral surface. Head brown; antennz testaceous at base, dark brown at distal extremity, about as long as thorax. The thorax, which is brown, and covered in parts by minute gray and black hairs, is testaceous or tawny at the sides. The abdomen has five triangular testaceous spots on each side, the second and the third each forming a band above. The wings have the veinlets of the pree-brachial areolet forming a slightly acute angle, the hind one nearly eight times the length of the fore one; the anal does not extend to the fork of sub-anal. The legs are long and slender and testaceous ; spurs long; tarsi brown. Length 1} to 2 lin. These are the only two common species in this genus, but the following also occur in England: /eptura, Mg., dorsalis, Staeg., indecisa, Wik., tarsata, Staeg., leioides, W\k., ferruginea, Wlk., flava, Wlk., and fuscula, Wik. GeEnus.—Alodia. Slender, tawny or brownish-black genus. Antennz sometimes cone-shaped. Resembles Aymosia, but the petiole of the second hind areolet is long. 122 AN ACCOUNT OF BRITISH FLIES. A. crassicornis, Stan. = on = o eo ie . Spinicoxa, Zett. This is a dark species. ‘The head is yellowish-red ; the palpi are yellowish. Antennz testaceous at the base. Antenne are stout, and in the ¢ longer than the thorax; in the 9? they are shorter and lanceolate. Head and thorax covered with a gray tomentum. ‘The thorax has a reddish-yellow stripe on each side ; these two stripes are broadest in front. The abdomen is yellowish- red (yellow according to Schiner) on the ventral surface, and also on the hinder parts of each segment. The ovipositor and male genitalia are testaceous, and sometimes brown. The wings have a yellowish tinge; the hind veinlet of the prz-brachial areolet about twice the length of the fore one. ‘The anal does not extend to fork of sub-anal. The legs are yellowish-brown, and fairly long; tibize and tarsi brown; fore tibia much shorter than the fore metatarsi. The spurs and spines on the posterior tibiz long. Length 2 to 24 lin. Fairly common at times. (‘M. grata, Mg. A. ornaticollis, Mg. = \M. lugens, Mg. M. analis. This is also a common species. It is testaceous, some almost dark brown. The head is dark brown, and the vertex has a white tomentum. ‘The thorax is also blackish-brown, the sides having a white tomentum. The proboscis and palpi reddish-yellow ; antennze dark brown, yellowish at the base. The abdomen seems to be liable to a large amount of variation, and there seem to be three distinct types of variation : («) Blackish-brown, with small yeilowish patches (=ornate- collts) ; (2) Entirely blackish-brown, with bright incisions (helleren Einschnitten) = Zugens ; (vy) Or blackish-brown, with triangular yellowish patches from the second to the fourth segment, and with testaceous anal segment { = gvaza). Walker, again, describes his ornadicol/is as having a large triangular blackish-brown spot on each dorsal segment. The legs are moderately long and testaceous; tarsi brown; posterior tibiz having longish spines; the anterior tibiz are much shorter than the anterior meta- tarsi. The wings are transparent and grayish, the costa and its neighbourhood being tinged with yellowish-red. Length 14 to 24 lin. THE MYVCETOPHILIDZE. 123 Genus.—Mycothera. Moderately small, dark brown and yellowish-brown genus ; wings with brown markings. Head round. Fourth joint of palpi long. Antennz 16-jointed. Eyes roundish; ocelli small, the middle one standing in a little cavity. Abdomen 6 or 7-jointed; hypopygium small. The wings large, and the petiole of the second hind areolet is short, not long as in Exechia. M. semtfusca, Mg. This is a dark brown species, and, according to Walker, it has a gray tomentum. The head is brown. ‘The thorax is also dark brown, with a testaceous spot on each side, has bright yellowish hairs on it. Abdomen dark brown; the ¢ genitalia small; the ovipositor tawny ; lamelle brown. Palpi testaceous. Antennz brown, about length of the thorax, testaceous at the base. Wings marked with pale brown across the middle and at the tips. Legs testaceous, tibize and tarsi brown ; posterior femora also brown at their distal extremity ; spines on posterior tibize very small. The anterior tibize longer than antericr metatarsi. Length 1} to 1} lin. This does not appear to be a common species, nor does the other one that is found in England, viz., AZ. dimidiata, Staeg. =ocellus, Wik. Genus.—Brachycampta, Wtz. The costal vein ending a little before the tip of the wing ; base of fourth hind areolet much nearer base of wing than is base of second hind areolet. Metamorphosis unknown. BL. bicolor, Macq. This gnat varies from rusty yellow to brown, with a grayish tinge. Head brown ; thorax brown and testaceous pectus ; abdomen testa- ceous, with brown markings. Anal segment small ; palpi testaceous ; antennz brown or black, testaceous at base, stout, shorter than thorax. Wings yellowish, with a brownish tinge. Legs yellowish ; tarsi brown ; the posterior tibiz2 have only a few spines, and very long spurs ; anterior tibiz nearly same length as the anterior meta- tarsi. This is an uncommon species, and the only one of the genus found in England. Length 1} to 2 lin. GENus.— Docosta, Wtz. The base of the fourth hind areolet ts in a line with that of the second hind areolet. Head oval, proboscis short; palpi bent, 4-jointed —first joint small, the fourth flat and very long. Antennz 16-jointed ; 124 AN ACCOUNT OF BRITISH FLIES. eyes round, ocelli three. Abdomen cylindrical, 7 segments, anal segment and ¢ genitalia small ; ovipositor short, two small lamellee. The larve live in fungi and rotten wood. The gnats are found in woods and thickets. D. sttarina, Mg.= M. gilvipes, Hal. This is a slightly ferruginous gnat, covered by whitish hairs. Palpi yellow ; antennze blackish-brown and thick ; the second joint has a long hair above. Eyes dark and oval; ocelli three in number, almost in a straight line. Thorax ferruginous. Wings minutely pubescent ; first, second, and third veins reddish-brown : ‘“ Das steile Basalstiick der dritten Langsader liegt verder Basis der Gabel der vierten Lingsader, bei .S. va/da liegtes jenseits dieser Basis.” The legs are rather stout and thick, tibize darker than femora; a thick row of small spines on posterior tibize, the spines are stouter in the hind tibiz ; tarsi brown. Length ri to 2 lin. Winnertz found the larve in Aoletus-scaber and edulis, and in Hydnum repandum ; also in rotten wood. The species J. valida is also found in England. It has a chocolate thorax, and is much darker than scéarvina. It appears in May. GrENvus.— Phronia, Wtz. This genus has been admirably worked out by Dziedzicki,* and a most detailed and true classification has been brought forward by him. After giving the characters of this genus and the two British species, I will then give a short account of the method of classifica- tion he has adopted. Characters of genus: Moderately small, rusty yellow to brown in colour. Head roundish, and segment large. Anterior tarsi always longer than the tibia. Wings rather short, costa extends now and then beyond the apex of the third longitudinal. The first longitudinal vein generally incomplete, sometimes it ends’ at the costa; fourth longitudinal vein with short petiole ; the fifth with a long petiole and generally a very small fork ; sixth and seventh longitudinal veins rudimentary. P. austriaca, Wiz. Head yellowish-brown. Palpi yellow. Antennz brown; first segment yellow. ‘Thorax yellow, with three dark brown stripes, which are confluent at their origin. MHalteres yellow, or whitish- yellow. Abdomen of six segments, dark brown above, yellowish- * Ent. Hor. Rosslande, t. xxiii., 1889. THE MVCETOPHILID A. 125 brown beneath. Legs yellow ; tarsi of the anterior legs 2-3 times longer than the tibiz of the corresponding legs ; the tibize are in the same proportion to the corresponding metatarsi. ‘The ovipositor: the pars basalia supera with a deep angular hollow on the posterior side, and with a slight arched depression on the sides ; the w hole ex ternal surface of the lamella almost bare, and not clothed with any little hairs. The pars éasalia infera: the posterior border notched in form of a parenthesis, and covered by a single row of small hairs. The anterior lamella cylindrical, with the surface covered by delicate hairs ; the superior edge has also a single row of long hairs. The fostertor lamella small, pyriform. Length 14 to 1 lin, They appear in May, June, July and August, according to Dziedzicki. P. nitidiventris, V. d. Wulp. The larvze of this species live in rotten wood. The ¢ organs blackish-brown. The posterior border of the lamina basalis is divided into three blunt lobes by two moderately deep cuneiform depressions ; the middle lobe is the largest and more convex than the lateral; the external surface is covered by delicate hairs. The forceps infertor is almost rectangular in form, the ex- ternal border larger than the internal ; the posterior border furnished by a row of strong and also long hairs; the whole external surface covered by delicate hairs. The forceps superior, sickle-shaped (faucilliforme), furnished on the posterior borders and on the internal with small hairs; in the middle of this last piece is a triangular lamella furnished on its superior border with a row of strong hairs ; on the external parts of the forceps are found mem- branous lamellze with rows of rods (agueftes). Ovipositor brown. The ars basalis supera: the posterior border is notched with three semicircular depressions, the middle one much deeper than the lateral ones ; the external surface is bare, and there is a fine and long hair at the posterior angle. The fars basalts infera is a truncated triangle in form, with the posterior angles rounded ; the external surface and posterior border are covered by delicate hairs. The azz, or superior lamella, is heart-shaped, depressed in a deep arch on the posterior surface; the external surface covered by minute hairs. The fost, or inferior lamella, is in the form of a button, and is furnished with some short and strong hairs. Length 14 to 1d lin. The zmago is found in May, June, July and August. The descriptions of these two British examples of the genus Phronia are taken from Dziedzicki’s monograph of the genus. He 126 AN ACCOUNT OF BRITISH GALS. bases his classification and specific characters on the sexual organs, viz., the Hypfopygium or & copulatory organs, and the ovipositor (Legerohre or? ), The great importance of these two parts cannot be over-estimated, as they form the most decisive specific characters. The colour and nervation of the wings, etc., cannot be relied on, especially in the Mycetids, where the variation seems to be very great, and although, as pointed out by Professor Mik, the use of the hypopygium and ovipositor as specific characters necessitates the destruction of the species, it is far better to do so and thus find out what the true species are, than to be adding numbers of species, which are mere variations in colour and nervation. Is it not far better to have the hypopygium or ovipositor of an insect identified than the perfect fly which we cannot definitely identify? ‘The great importance of these organs cannot be valued enough as specific dis- tinctions. I will now give an account of the A/yfopygium and Ovtpositor (of the genus Phronia). The Aypopygium (Fig. 24). This is composed of the following Fic. 24.— gd genitalia=hypopygium of Phronza. I. and II. A=laminz basalis ; B=lam. super ; C= forceps superior, D forceps inferior ; III. =forceps superior. parts : (i.) Zamina basalts ; (u1.) amine supere ; (iil.) forceps inferior ; (iv.) forceps superior ; (v.) and the appendix interna, or adminiculum. (i.) The Zamina basalis, which forms the greater part of the hypopygium, is attached to the sixth abdominal segment by the modified two last segments (seventh and eighth). The posterior surface of the lamina is indented in various THE MVCETOPHILIDA, PG) ways in the different species ; the forceps join the poste- rior surface. (ii.) The Zamtne supere are two in number and lanceolate. They cover the summit of the lamina basalis. They are movable, and easily elevated upwards or downwards. There are two plates at the base of the lamine. (i.) The forceps tnfertor simple, often notched and curved in various ways, and very hairy. This part forms a great specific character. (iv.) The forceps superior formed of three distinct parts: (1) The “trone” (4), which varies a great dealin form. (2) The “lamella” (¢), which is generally a triangular plate, the superior border being furnished with spines, which are long and strong. (3) The ‘‘ membranous lamella” (a). This is wrinkled in various ways and furnished with recumbent, horizontal rows of rods (daguettes), smooth and compact. There is also another lamella present, joined to this, oblong in form and variable in shape, directed towards the interior; a few hairs present. (v.) The appendix interna, or adminiculum. ‘This is found to be present in the middle of the basal lamella and beneath the two laminz super. ‘They are small structures, and not easily found in Mycetids. The Oviposttor (Legerohre). This is also composed of five parts: The pars basalts supera; the pars basalis infera ; the lamelle ante- riores ; the damelle posteriores, and the vaginula. (Vide Fig. 25.) (i.) Pars basalis supera (A). This corresponds to the eighth dorsal abdominal segment. It is a simple plate, which is indented on the posterior border in various ways. (il.) The pars basalts infera (E). This corresponds to the eighth ventral abdominal segment. It is also a simple piece, with various indentations in the different species. (iii.) The Zamelle anteriores (B) are movable plates of various shapes, the superior border being edged with a few long hairs. (iv.) The Zamelle posteriores (Cc) are joined to the lam. ant., and are surmounted on their summit or extremity by short, strong hairs. (v.) The vagénula(p). This underlies the ant. and post. lamelle. Of course these parts vary, not only in each family, but in each genus and species ; their study is at present in a very unsatisfactory state 128 AN ACCOUNT OF BRITISH FLIES. By this means alone will a satisfactory separation of the species of Mycetophilide be accomplished. ‘The paper from which this has ; Dias vax ian Fic. 25.— ¥ genitalia =ovipositor (Legerohre) of Phronia. been mainly compiled shows amply the great specific importance of the structure of the sexual organs. GENUS.—Sceptonia, Wtz. This is a small, dark-coloured genus. ‘The middle tibia has one row of black spines on its inner surface. ‘The costa passes beyond the apex of the third longitudinal. The anal is incomplete (sixth), and the seventh longitudinal vein is very long. The larvee live in fungi and rotten wood. ‘The gnats are found in shady woods. S. nigra, Mg. This is a black species, about 14 to 1} lin. in length. The head is black ; the palpi testaceous ; the antennze black, testaceous at the base. The anal segment and hypopygium testaceous ; the ovipositor brown, with yellow lamellze. Legs testaceous; tarsi brown; black tips to femora; fore tibize longer than fore metatarsi. Wings yellowish or with a brownish-yellow tinge (Walker describes them as gray). This fly appears in woods and thickets fairly plentifully from April to October. GENUS.—Zygomyia, Wtz. Head roundish; proboscis short; palpi, eyes, and ocelli as in Exechia. Forehead drawn forward in a triangular shape ; head with LHE MY CELOPAILID ZA. ~ 129 anterior border somewhat projecting. Legs tolerably long, anterior — ones shortened; femora strong and thick; posterior femora very thick ; tibize strong, club-shaped, spurred ; anterior ones devoid of spines ; posterior with two rows of strong lateral spines ; posterior tarsi with fine spines. Abdomen 6 to 7 jointed; ¢ genitalia small. Wings minutely hairy. Z. notata, Stan. This is a blackish-brown insect ; head dark brown ; palpi yellow ; antennze brown, with yellow base ; glistening yellowish-gray hairs on the abdomen. Anal segment small, yellowish. | Ovipositor and lamellz brown. Legs testaceous, the apex of the hind femora brown. Wings with a yellowish-gray tinge; root and costa yellow, with a discal brown spot. Length, } to r} lin. This gnat is found in woods and copses, the larve living in rotten wood. ‘There are the following also found in Britain: Valida, Wtz. (Verh. d. Zool. Bot., Ges. xili., go2-1. 1863.) Pictipennis, Staeg. (Staeger, Kroj., Tidskr. ii., 266-41. 1840). Vara, Staeg., cbzd., 42 ; and paludosa, Staeg. GENuS.— Azana, Wk. Small dark insects. Head small and oval; lower than thorax. Palpi small and short. Antennz stout and 16-jointed, not longer than thorax. The thorax is convex. The abdomen is compressed and of moderate length, the anal segment blunt and the hypopygium small. Wings fairly broad. ‘The costa passes beyond the apex of the third longitudinal vein ; fourth and fifth longitudinal veins simple ; sixth rudimentary. ‘Transverse veinlet small, long, and nearly hori- zontal. Metamorphosis unknown. A. anomata, Staeg. = A. scatopsotdes, Wk. This is the only species in this genus, and was first described by Walker. The gnat is black, with grayish wings; yellowish hairs. The head, palpi, and antennze mostly black ; the base of the latter occasionally testaceous. Legs piceous, stout, and long ; hind tibize with minute spines and fairly long spurs. ‘Tarsi brown. Halteres tawny, with black knobs. Length, about 1} lin. This genus is closely allied to Mycetophila. Appears in May and June. GENuS.—Acnemia, Wtz. Head round; flat in front; proboscis short ; antenne 16-jointed, arched. Eyes oval. Ocelli three, the middle one small ; some- 9 130 AN ACCOUNT OF BRITISH FLIES. times in a straight line. Abdomen cylindrical, with large anal segment and small hypopygium, short ovipositor, and two strong lamella. Legs long, stout, and strong. Wings longish and rounded. The costa passes beyond the apex of the third longitudinal. The upper and lower branch of the first longitudinal form together one transverse veinlet. The fourth longitudinal vein is forked, and the fork has a short petiole ; sixth longitudinal vein very short. The larvee live in fungi and rotten wood. A. defecta, Wik. The perfect insect is black. Testaceous palpi. Antenne 16- jointed, sub-moniliform, a little longer than thorax. Abdomen testaceous at the tip. Wings nearly limpid, first longitudinal vein joining costa before one-third length of wing, united by a little trans- verse veinlet with the second longitudinal vein, at some distance from its tip; the second is united to the third by a veinlet, which is a little beyond the base of the fourth vein ; third joining the costal near the tip of the latter; fourth and fifth slight, the former forked near its base. Legs testaceous; trochanters partly black; spurs long ; tarsi blackish, minutely setose beneath. Length, 1 lin. This species seems only to be described by Walker, from whom this account is compiled. A. nitidicollis, Mg. Black with shiny hairs, thorax shiny ; hypopygium and lamelle of ovipositor yellowish; antennz 16-jointed, brown; palpi yellowish. Legs testaceous ; tarsi brown ; base of legs brown. Wings brownish ; base and veins brown. Length, 14 lin. A. amena, Wtz. This is a yellowish species also found in England. Length, 2 lin. GENuS.— Glaphyroptera, Wtz. Most of the species in this genus seem to have been placed in the old genus Zea, and many of them are described under this head by Walker and Meigen. Head roundish, flat above ; proboscis short ; palpi 4-jointed; fourth joint very long—as long as the three preceding ones together. Antennz 16-jointed. Eyes oval ; ocelli three, in a semicircle ; central one small; lateral ones large near the eyes. Thorax very convex. Abdomen with seven segments, slender, short anal segment and small genitalia (¢). Legs fairly thick ; tibize with long spines. Wings generally with spots or bands. Fourth and fifth veins forked. THE MVCETOPHILIDA:. 131 (Z- Jasciola, Mg. L. flavicornis, Mg. | L. consobrina, Curtis. L.. crucigera, Zett. G. fascipennis, Mg. =- This gnat is yellowish, with testaceous ventral surface. Palpi yellow ; antennz brown, yellowish at the base. Legs yellowish- brown, with brown tarsi. Wings with a yellowish tinge, testaceous at the base, and having a gray sub-apical band. ‘The first longitudinal vein short, united to second longitudinal vein by a transverse veinlet ; fork of the fifth longitudinal vein much nearer than the fork of the fourth to the base of wing. ‘This is an abundant species, and is. especially common on oak and lime trees. There are about a dozen of this genus found in England—the one described is the commonest. The larve live in fungi and rotten vegetable matter. The larva of G. fasciola, Mg. (fascipennts) is described by Van Roser* as follows : ‘‘The transparent, smooth and slimy larva lives in delicate webs on the surface of tree fungi.” They strongly resemble Sciophida \arvee in habits and structure. G. Winthemii, Lehm. = Leta Winthemii Wik. (Ins. Brit.). This species is testaceous. The thorax has three brown stripes, the middle one being divided. Wings with three gray bands, which seem to vary, sometimes being almost absent. Abdomen has a dark band on each segment at the ventral edge. An autumnal species. Recorded by Dale at Glanville Wootton. G. subfasciata, Mg. = Leia Marklini, Zett., is the only other cer- tain British species ; there are many others recorded as British, but their records want verification. G. pulchella, Curt., is a bright ochreous species, with a dark spot on the thorax ; the first and second abdominal segments have a black spot ; third, fourth and fifth have a black ring; sixth and seventh black. Recorded by Curtis and Haliday, and taken on umbelliferz. ; Mycetophila, Mg. GrNus Anaclinia, Wtz. = < Leta, Macq. Loletina, 7ett. This genus resembles Leffomorphus, but the ocelli are nearly of the same size, and are arranged in a straight line. Abdomen flattened laterally. Wings microscopically hairy; third vein, simple; fourth and fifth forked ; sixth vein not extending to the edge of wing. Zhe costa extends over the apex of third vein. * Verz. Wiirttemb. Dipt., 1834. 132 AN ACCOONT OF BLATTISH FTEs. A. nemoralis, Mg. = Boletina elongata, Curtis. Blackish-brown. ‘The body long, slender, shining ; head brown ; hairs yellowish ; thorax with a tawny spot on each side in front. Palpi yellowish; antennz blackish-brown, yellowish at the base. Wings with brownish tinge, yellowish costa and brown veins; third longitudinal vein undulating; fourth longitudinal vein not forked, but accompanied by a secondary vein, ending behind the tip of the wing ; fork of fifth and tip of preebrachial areolet at an equal distance from the base of the wing ; sixth vein fairly long. Legs testaceous, long and slender ; brown at their base and also the tarsi ; hind tibize brownish, no spines. Length 3 lin. Not an uncommon gnat. The life history unknown. Mycetophila, Mg. Genus Loletina, Staeg. = < Leia, Mg. Leptomorphus, Wik. This genus of gnats much resembles the Mycetophilz, but they are of a more slender build than the latter, and the sub-costal, or first longi- tudinal vein, is much longer. The following may be taken as the chief characters of the genus: Body 7-segmented and slender, cylindrical in ¢, subfusiform in 9; thorax large, convex, short ; head small, and ventrally placed; eyes oval, ocelli three, central one below lateral ones and small; the palpi are curved outwards. Proboscis scarcely elongated. Antenne slender, 16-jointed compressed, about twice the length of thorax in the 3, and about same length as thorax in the 9 ; very few hairs. Wings broadish; costal vein not long, scarcely reaching tip of wing; first longitudinal vein long, nearly half length of wing ; second longitudinal straight, not ending quite at the tip; third longitudianl vein joins tip of costal; fourth and fifth forked; sixth distinct, but not reaching the border of the wing; seventh small. Legs slender, of moderate length ; a few bristles on the tibize ; spurs longish. Hypopygium and ovipositor small. These gnats frequent woods and damp places, and in their habits they much resemble Mycetophile.. The larvee live in fungi andin rotten wood. Beling* describes one from rotten and ‘decaying leaves in a forest of deciduous trees” in Denmark. Closely allied to this genus is Gvoriste, which is not, however, found in England. ‘The Boletinz seem to be northern insects, many béing found in Norway, Sweden, Greenland, Lapland, etc. ; but they are equally abundant in warmer climates. * Wiegm. Archiv., etc., 1875, p. 56. PE MVCELOPAILID A, 133 B. dubia, Staeg. This is a black gnat. Head and thorax covered by a gray tomen- tum ; antennez slender, 16-jointed and a little longer than the thorax. The abdomen is long and dark. Wings have the fork of the fifth longitudinal vein nearer to the base of wing than the fork of the fourth longitudinal vein ; sixth extends nearly to the fork of the fifth. Legs testaceous, long and slender ; tibize dark, posterior tibize witn long spurs and short spines: tarsi black. Length 3 to 34 lin. Mycetophila sciarina, Mg. MM. obscurella, Zett. This is a blackish-brown species, very widely distributed. Zetterstedt describes it from Norway, etc., under the name odscure//a. It 1s, according to Walker, slightly covered by a gray tomentum. Palpi and antennz are blackish-brown; the antenne are twice the length of the thorax. The body is clothed with yellowish hairs. The anal segment is longer than the one before it. The legs are testa- ceous, and the spurs short ; tarsi blackish-brown, and the hind tibiz with very few short spines. The wings have a grayish tinge ; second and third longitudinal veins very distinct, brown ; the fourth and fifth pale ; the sixth fairly long, extending beyond the fork of the fifth. Length 14 to 2 lin. The other British species are ¢rivittata,* Mg. (System. Beschr. 1. 258, 10); borealis, Zett. (Dipt. Scand., xi. 4,160, 8); plana, Wk. (Ins. Brit., vol. ili., p. 34) ; azalis, Mg. (System. Beschr., i., 257, 9). B. sctarina, Staeg. = \ GENUS Leptomorphus, Curtis. This genus was formed by Curtis, one species only being known. The body is slender ; head small ; palpi 4-jointed, long and slender, WEE 5 Fic. 26.—Head of Leptomorphus Walkert. fourth joint longest. Eyes oval ; ocelli two. Antenne 16-jointed, filiform, about half length of body. Thorax very short. Abdomen compressed, thickened at the tip; the hypopygium large. Legs long and slender, very small spines to tibie and very long spurs. Wings narrow, hairy ; costal ends a little in front of tip of wing ; first longi- tudinal vein long, connected with the second by a transverse veinlet * Taken at Linton, Ivybridge, Loch Maree and Tongue, in June. (Verrall.) 134 AN ACCOUNT OF BRITISH FLIES. near its junction with the costa; there is another transverse veinlet near this, between second and third veins ; the third longitudinal is united with the tip of the costa, and is not forked ; the fork of the fourth much beyond the fork of the fifth, which is nearly opposite the transverse veinlets ; the sixth extends beyond the fork of the fifth. This is figured by Curtis. ‘The metamorphosis is unknown. L. Weatlkeri, Curtis. Testaceous ; head tawny ; thorax with three blackish-brown stripes, united behind. Palpi and proboscis testaceous; antennz brown, yellow at the base. Ocelli brown. Abdomen brown towards the tip, posterior borders of the segments darkish, the hypopygium golden yellow ; yellowish hairs. Wings grayish at the tip; a brown spot at the tip of the preebrachial areolet; veins dark brown. Legs testaceous ; tarsi brown and spurs dark brown. Length 5 lin. Mr. Dale found this species in September at Glanville Wootton. The flight much resembles that of a Plume Moth (/%erophorus). SECTION 3.— Fic. 27.—Head of Zetragoneura Sylvatica. before tip of wing: base of the fourth hind areolet in a transverse line with the base of the second, or very near the base of the wing. Joints of the antenne cylindrical. The larvee live in fungi and rotten wood. LD hiria, Witz = (Sea sstmiiliss Lett. Black, clothed with whitish hairs. ‘Thorax with grayish tinge, beset with large light hairs. Abdomen in ¢ dark brown with light hairs and somewhat shiny, ventral segment yellow; in the ? the abdomen is yellow, the segments have a black dorsal stripe and black bands, except the sixth and seventh segments, which are entirely black. Hypopygium yellow; ovipositor and lamella brown. Head dark brown, vertex sometimes grayish ; proboscis and palpi yellow. An- tennz dark brown, basal and second joints yellow. Wings hyaline, costa dark, areolet oblong ; second and third longitudinal veins brown, the rest pale; the first longitudinal ending in the second before its middle ; fork of fourth longitudinal opposite apex of areolet ; fork of the fifth nearly at the base of the wing. Legs light yellow ; coxee and tips of posterior femora dark brown, the latter has a black streak at the base on the ventral side; tibiz and tarsi brown ; posterior tibia longer than metatarsus. Length 14 lin. This is a rare species. Haliday records it from Ireland. There are two other species of this genus recorded from Great Britain, viz., sy/vadica, Curtis, Brit. Ent., xiv., 641, 16 (1837), and Winnertz, Verh. d. Zool. Bot. Ges., xill. 766. 2 (=distincta) and melanoceras, W\k., vide Walker, Ins. Brit., Dip., vol. iii., p. 46.1 * Ent. Zeit. V., Stett. vii. 18 (1846). + Sylvatica=Black ; proboscis, palpi and second jocnt of antennz yellow. SU a THE MYCETOPHILIDA. 137 The round head and circular eyes, the ocelli being nearly equal and in a curved line, and the cylindrical joints of the antennz, be- sides the veins, at once distinguish this genus. Grnus.—Lastosoma, Wtz. = Sciophila, Mg. The larvee of this genus live in fungi and rotten wood. The gnats may be found in woods and thickets. The genus may be distinguished by the base of the fourth hind areolet being much further from the base of the wing than is the base of the second hind areolet. It is nearly allied to Sciophila, but the costal does not extend to the tip of the wing as it does in Scophila. There are seven species of this genus found in Great Britain. (S. Aerta, Hoffm. \S. pilosula, Zett. Blackish-brown. Head brown. Palpi testaceous ; antennz longer than thorax. Abdomen brown. Legs yellow ; tarsi brown, yellow at the base; posterior femora dark at the base and tips ; posterior tibize also dark at the tips. Wings with a brownish-gray tinge; first cubital areolet of moderate size, oblong. ‘This is a fairly abundant species. Length 15 to 2 lin. L. rufilaterum, Wik. = S. rufilatera, W\k. This is a dark brown insect; palpi yellowish ; antennze blackish- brown, tawny at the base. Thorax with a tawny spot on each side in front. Abdome tawny on each side, except towards the tp. Legs tawny ; tarsi brown; posterior tibiz with minute spines and rather long spurs. Wings grayish. First cubital areolet very small, almost sguare. Length 1} lin. Scarce species. The following are the other British species : L. luteum, Macq. Dale has bred this species from larvee feeding in a web on a fungus on a pear tree. The imago is yellowish, with dark brown head. L. ochraceum, W\k., Ins. Brit. Dip., vol. i., p. 41. LZ. maura, Wlk., zétd. p. 42. L. fenestredla, Curtis, British Ent., 641 (1837). L. rufum, Mg. | L. hirtum, Mg. = GENus.—JMonoclona, Mik. M. halterata, Staeg. This is a rare species, resembling S. (Z.) vufum, Mg., in appear- ance. ‘The zmago is testaceous ; the head has front and vertex dark- Thorax blackish-gray, beset with long whitish-yellow hairs. Areolet minute. Abdomen as in #z7fa. Sub-costal obsolete. Melanoceras = Antennze gzte black. Sub-costal complete. Areolet elongated and dilated at the tp. Holywood, near Belfast (Haliday). 138 AN ACCOUNT OF BRITISH FLIES. brown ; the thorax shiny and covered with pale hairs. The abdomen brownish. Palpi brownish ; antenne dark brown, first and second joints yellowish. Legs short, yellowish ; posterior tibiae have short, but distinct spines. Wings hyaline; veins stout and brown ; areolet small; first longitudinal vein connected with second before the areolet ; fork of fourth longitudinal vein with very short petiole. Length 23 lin. ‘This species may be known from Z. rufum by being shorter in legs and antennz and by the stout veins. (Platyura, F. SASS p \ Asindulum, Lat. In this genus ¢he costal vein extends to the tip of the wing. The body is slender and elongated. Head small. Proboscisshert. Palpi four-jointed, fourth joint long and slender, first and second joints short. Antenne 16-jointed, as long in 2, longer in ¢, than head and thorax. Eyes oblong; ocelli three in number. ‘Thorax short, with black hairs. Abdomen slender, seven segments, cylindrical in 6, fusiform in 9. Legs long and slender; femora hairy, tibize setose ; spurs moderately long. Wings moderately broad, minutely hairy ; first longitudinal vein slightly curved towards its tip, often united with costal, and connected with second longitudinal near its tip by a transverse veinlet ; third longitudinal arises from the second before the middle of the wing ; fourth longitudinal forked at beyond the middle of wing; fifth forked, forks nearly straight ; seventh very near the base. Areolets twelve, including two cubitals. S. tenuis, Wik. This gnat is slender and tawny. Head tawny, vertex black. Palpi and proboscis yellowish ; antennze dark brown, yellowish at the base. Thorax has three dark stripes, the middle one long, the lateral ones short. Abdomentawny. Legs yellowish, long and slender ; posterior tibize with minute spines and very short spurs. Wings nearly limpid ; transverse veinlet springs from the first longitudinal vein opposite the middle of the first cubital areolet. Length 24 lin. Appears to be uncommon ; found in August. S. fasciata, Zett. Yellowish ; head with vertex black ; antennze dark, yellowish at the base. Three black stripes on the thorax, lateral stripes short. Abdomen black, with a yellowish border on the posterior edge of each segment. Legs yellowish; tarsi brown; posterior tibiae with LHECMVCELOPHLILID A. 139 minute spines and long spurs. Wings with a faint brownish tinge ; cubital areolet not clouded. ‘Length 2 to 3 lin. Fic, 28.—Sctophila Fasciata. This is a common species, and resembles .S. marginata, but the latter has the cubital areolet clouded. J/arginata, Mg., is 24 to 3 lin. long. As far as I can make out, S. Az/aris, WIk., is the same as fasciata, Zett. Other British species are : S. hyalinata,* Mg. Verh. d. Zool. Bot. Ges., xill., 713, 6. S. congrua, Wik. ‘This is a black species, with tawny palpi; a ferruginous spot on each side of the thorax in front; scutellum and pectus ferruginous. S. trivittata, Zett. Gray, hoary beneath. ‘Testaceous spot on each side of thorax in front. Abdomen testaceous beneath and along the hind borders of the segments on each side. Found in May. Sicueniae New “Meig tric 1; 102.8515 ZW. 1247, 5 (1o1o): S. ornata, Mg. Winnertz, Verh. d. Zool. Bot. Ges., xiil., 725, 18. S. fimbriata, Mg. Jdid., xili., 736, 29. Meigen, Zw., 247, 3. S. ferruginea, Mg. Zw. 1., 249, 9. S. ruficollis, Zett. ? Zetterstedt, Dip. Scan., xi. 4121, 17. S. punctata, Mg. Winnertz, Verh. d. Zool. Bot., Ges., xill., 714, 7. * Hyalinata, Mg. Testaceous ; vertex black, abdomen brown, hind borders of segments testaceous. Cingulata, Mg. Testaceous ; vertex brown. fimbriata, Mg. Tawny ; vertex piceous. Ferruginea, Mg. Testaceous; vertex black; brown band on hind border of each abdominal segment. Rujficollis, Zett. Testaceous ; sutures and tip of abdomen black. Punctata, Mg. Tawny ; vertex black. Trilineata, Zett. Testaceous ; abdomen pale ferruginous. Incisurata, Zett. Testaceous ; vertex brown. Abdomen brown ; pale testaceous band on hind border of each segment. Ornata, Mg. ‘Testaceous ; abdomen testaceous ; second to fifth segments with black borders. 140 AN ACCOUNT OF BRITISH VALTE:S: S. trilineata, Zett. Lbid., xii. 734, 27. S. zncisurata, Zett. = S..annulata, Mg.~ Ins. Lapp., 859, 7 (1840). Zett. and Zw.,1., 247, 4 (1818). Meigen. SECTION 4.—Ceroplatine. Antenne 17-jointed, not very long. Ocelli three, middle one small. Thorax elliptical. First longitudinal vein short ; third, fourth and fifth veins forked ; brachial vein short. Body long and narrow ; eight segments. A. Mouth elongated like a beak. Tipula, ¥. GENUS Asindulum, Ltr. = | Platyura, Zett. Macrorrhyncha, Wtz. The insects of this genus are slender, and their bodies are long. Head (Fig. 174) oval and depressed in front ; vertex convex ; front broad. Eyes oblong ; ocelli three, middle one small. The mouth is produced into a short rostrum: the proboscis is long and bifid, elongated lips. Palpi 4-jointed ; first joint small, third and fourth fairly long and nearly equal. Antennee: first and second joints cyathiform, re- mainder cylindrical, except seventeen, this is conical; hairy. Abdo- men cylindrical, eight segments; in 9 the abdomen is subfusciform ; hypopygium small. Legs long and slender; hind femora stout and bare ; hind tibiz: have minute lateral spines ; spurs well developed. Wings minutely pubescent, parallel in repose ; first longitudinal vein short, second ending much beyond half the length of the wing ; fourth longitudinal, forked near its base, fore-fork ending just behind tip of the wing ; fifth forked nearer base of wing, its fore-fork connected by a transverse veinlet with the third longitudinal vein before the fork of the fourth ; the sixth and seventh veins short. The metamorphosis is not known, but Winnertz* reared them from rotten wood. (A. flavum). A. flavum, Wtz. = P. rostrata, Zett. The zmago is yellow. The thorax yellow, with three brownish stripes running longitudinally, clothed with black hairs. Proboscis, palpi and antennz blackish-brown. Abdomen brown in the dg; first and second segments yellow ; sixth, seventh and eighth black ; hypopygium light brown to yellow. In the 9 the abdomen is pale brownish-yellow ; third, fourth and fifth segments with black sutures ; the seventh and eighth black; ovipositor light brown. Legs pale * Stett: Ent, Zeit., 1846, p. 18. THE MY CELOPALLIDA. 141 yellow ; tibiae pale brown ; tarsi brown. ‘The wings have a yellowish tinge. Length 2 to 22 lin. ‘This is a rare species, and the only one of the genus found in England: the larvze live in decayed wood. B. Mouth not elongated like a beak. Genus Platyura, Mg. Body long and narrow. Head roundish, small. Pvodoscts short. Eyes round ; ocelli three, the costal one small. Palpi bent together ; 4-jointed ; first small, second and third large, fourth long and slender Antenne stout, not dilated as in Cevop/atus ; 17-jointed, joints trans- verse. Thorax short. Abdomen depressed, cylindrical in ¢, seven segments. Legs long and slender, tibiae without spines, spurs moderate. Wings are bare, and sometimes clouded ; first vein curved forwards towards its tip ; third forked, connected with the second at before one-third of length, when it forms a curve near its junction with the transverse ; the upper prong of fork may end on the second vein or on the costal ; fourth vein short, arises from the third, forked, fork long, petiole very short; fifth also forked, hind prong passing in a curve to the posterior border ; sixth vein reaches the border ; seventh small. Areolets thirteen. The habits of this genus seem to resemble Mycetophila, most being found in woods and thickets, and the larve living upon fungi and rotten wood. At present very little is known about the larve. Meigen* mentions one, P. marginata, being foundina fungus. The species of this genus tabulate as follows :+ a. Fork of third longitudinal vein joins second longitudinal vein - - = marginata, Mg. aa. Fork of third joins costal. b. Fork rather long. atrata, F. c. Fork curved - = - - - =< nigriceps, WIk. ( mycetophiloides, \W\k. ce. Fork straight - - - - - = Uitripennis, WIk. bb. Fork short. ( antica, Wik. c. Wings spotted - - - =e ASCH GUT flavipes, Mg. * Meig., vol. i., p. 232, et Verh. Sch. Ges., 1837. p. 106. + Walker, Ins. Brit., ili., 65. 142 AN ACCOUNT OF BRITISH FLIES. untcolor, W\k. servula, Wik. aiscolaria, Mg. concisa, Wk. cc. Wings unspotted - - - -_ = P. marginata, Mg. This is a black shining species. Proboscis and palpi tawny. Antenne a little longer than the thorax. Abdomen long and black, with ferruginous markings in the 9. Legs testaceous ; tibiz tawny, tarsi brown. Wings yellowish-gray, clouded with gray towards the tips and along the hind border, and with a slight brownish spot at the base of the fourth longitudinal vein; in the ? the discal brownish spot almost obsolete. Length 3} to 5 lin. Not common; found in woods, especially hazel woods. iP. jasciara, itr. — J ruficollis, Mg. ‘ | ochracea, Mg. This is a tawny species, with short and slender brown antenne, tawny at the base, as long as the thorax in the ¢, shorter in the 9. Thorax with dark longitudinal marks. Abdomen with a black band on the fore-border of each segment ; hypopygium brown ; lamellz and ovipositor yellow; hairs on the body black. Legs testaceous ; tarsi brown. Wings with a pale yellowish tinge, and with a grayish sub-apical band, which is very obscure towards the hind border. Length 3 to 34 lin. Common in July. P. concisa, Wik. Black. Proboscis and palpi tawny. Antennze black, tawny at the base. Pectus and sides of the thorax piceous. Posterior borders of abdominal segment testaceous. Legs yellowish ; tarsi dark brown. Wings grayish-yellow, unspotted. Length 2 lin. This seems to be a rare species, described shortly by Walker. P. unicolor, W\k., is also black, with brownish wings, paler in the disc towards the base, with black veins, ferruginous at the base. Legs ferruginous, tarsi black. Length 3 lin. Rare. The other British species mentioned in the table are all, as far as our scanty knowledge goes, uncommon. | //avi~es is, however, recorded as ,;common at Glanville Wootton. This is a black species, witn the hind borders of the abdominal segments testaceous. Length 13 to 2 lin. Atrata is a very rare species, appearing in July and August. THE MV CELOPAILID 4. 143 Shining black, with a sub-apical brown spot, in front, on its gray wings. Length 3 to 34 lin. Discolaria frequents lime trees. It is a tawny species. The anterior borders of the abdominal segments are brown, and the wings have a reddish-brown tinge. About 2} to 2} lin. (=descolor). Re- corded from Glanville Wootton and Kingston. Vitripennis is black, covered with hoary tomentum. Dale considers it a var. of atrata. Glanville Wootton. { Rhagio et Sciara, F. | Platyura, Mg. Head small. Proboscis short. Antennz 16-jointed ; broad and short, dilated; thorax oval. Palpi not bent together as in Platyura. Abdomen seven segments. Eyes oval, depressed in the inner sides ; ocelli three, the central one small, nearly in a straight line. Legs longish, tibia with spines and spurs; femora and tibiz short, rather thick, metatarsi long. Wings minutely hairy, short ; often shorter than the body. GENUS Ceroplatus, Box = Fic. 29.—Ceroplatus Lineatus. A. Palpus. The larvee(Fig. 148) of this genus resemble in habits Scophi/e larve, living in webs on the under surface of the pileus of tree fungi. Before the larvee (which are white and slimy) pupate, they leave this web and spin a silken cocoon, near at hand; the cocoon is truncate at one end, and, according to Wahlberg,* closed with a lid. This observer also noticed the phosphorescent character of the pupze, which even shine through the silken cocoon. Dufour} figures * Acta. Holm. 1838. + Ann. des. Sc. Nat., 2nd series, vol. xi., 1839. 144 AN ACCOUNT OF BRITISH FLIES. the larvee as having four large posterior segments and the remainder of the body, leech-like, marked by numerous annulations. Boscs* describes an American species, but talks of its body as having distinct segments. This does not answer to Dufour’s description of the leech- like body. There is only one species found in England, as far as we know. C. lineatus, F. = P. laticornis, Mg. Tawny. Thorax tawny, with three brown longitudinal stripes ; pectus brown ; metathorax brownish. Abdomen blackish-brown or black ; there is a yellowish band with a spot on each side on the anterior borders of the third, fourth and fifth segments ; hypopygium brown ; ovipositor and lamelle yellow. Head brown, proboscis and palpi yellowish. Antennze broad, brown, testaceous at base, about as long as the head and thorax. Legs yellow; base of tibize and tarsi brown, also base of femora ; metatarsi of the anterior legs longer than tibize ; spines and spurs of the latter brown. Wings shorter than the abdomen ; grayish, with apex brown, also a brown spot near the centre and one below at the posterior border of wing. Length 3} to 3 lin. Walker describes P. dincata F., and P. laticornis. The latter is most likely the & of lineata. We gives the length as 5 and 4 lin. P. (C.) daticornes is figured, pl. xxiii., fig. 5. This figure resembles P. (C.) /éseatas F. SECTION 5.—JZacrocerine. Antennz very long, filiform, 16-jointed ; may be three times as long as the body, longer in ¢ than inthe ¢. Body slender, pubes- cent. Head small, ocelli three, eyes nearly round. Labium forming two large pubescent lobes. Palpi 4-jointed, second smaller than the —— ee ana ene pe Ba tg gy Si =X A v Fic. 30.—Antenna of a Macrocera, °. first, fourth fairly long. Thorax short and elliptical. Abdomen cylindrical in 3; elongate, fusciform in ?. Legs long and slender ; tibiz without spines; their spurs very small. Wings moderately * Dict. d’Hist. Nat., vol. iii., 1823. Figure of larva in the second edition of same, Tab. B. 21, fig. 4. THE, MV CEVO PALLET 2. 145 broad ; third longitudinal vein forked, arising from the second at before one-third of the length; fourth emerges from the third at before half the length, near which it is forked ; fifth also forked, hind prong very much diverging from the fore one ; sixth extending to the hird border. Areolets thirteen. These flies can at once be known by their elegant appearance and! very long antenne. ‘They are fond of nettles in shady woods, and: are often found resting on palings with the long antennze extended. They are the most elegant of all this family. The characters of the: section are the same as the genus, there being only one genus in this» section. The seven species found in Britain are tabulated by Walker, and as this seems the best method I can find I append it below : «. Antenne two or three times length of body. 8, Wings unspotted. y. Thorax striped - : - - = wittata, Mg. yy. Thorax not striped - . =e liacas Noe 68. Wings spotted. y. Tips of wings not clouded. 6. Thorax not striped =) = stema, Curt. 60. ‘Thorax striped - : - - = centralis, Mg. yy. Tips of wings clouded. 6. Wings striped between the tip of the | second and fork of the third vein= J 66. Wings striped before the tip of second | phalerata, Mg. angulata, Mg. vein - - - - - aa. Antenne not longer than body - - = fasciata, Mg. M. vittata, Mg. = MM. dorsalis, Curt. This is a tawny species. Yellowish on the ventral surface. Palpi yellow. Antenne blackish, yellow at base; as long as body. Thorax with three dark reddish stripes ; the median one long, the lateral ones short. The abdomen is tawny, with a dark brown dorsal stripe. Legs yellow ; tarsi brown. Wings grayish, with yellowish tinge at the costal edge. This is a common species, found resting on park palings. Length 3 to 4 lin. M. fasciata, Mg. This is a yellowish species. Thorax with three brown stripes ; lateral pair short. Abdomen yellow, with an interrupted dark brown dorsal stripe, and a brown band on the anterior border of each seg- ment ; hypopygium brown ; ovipositor and lamelle yellow. Head Lo 146 AN ACCOUNT OF BRITISH FLIES. yellow, brownish beneath ; palpi yellow; antennz shorter than the body ; brown, yellowish at base. Legs long, yellow ; tarsi brownish- black, with black hairs. Wings grayish. Length 23 to 3} lin. Walker mentions a variety with testaceous bands on the antennze. The other five British species are all fairlycommon. JZ centratts, Mg., angulata, Mg.=vittata, Macq., and stigma, are described in Curtis’s ‘ British Entomology’ (637, 3), (637, 2) and (637, 6). 1837. M. phalerata, Mg. (Verh. d. Zool. Bot. Ges., xili., 683, 13.) M. lutea, Mg. (Meigen, System. Beschr., 1., 223, 1.) M. maculata, Mg., is also described by Curtis (B. E., 637, 4), but is placed amongst the reputed species by Verrall. SECTION 6.—Solitophiline. This section again only includes one genus, so we may combine the characters of genus and section together. Body slender. Head small. Eyes round and prominent. Ocelli three, nearly in a straight line. Labium short and broad. Proboscis short. Palpi 4-jointed, cylindrical ; first, second and third joints short, fourth long and slender. Antennze 16-jointed, slender, seti- form, shorter than body; apex attenuated, but not segmented ; pubescent in ¢, longer than 9; in the latter they are bare. Thorax long. Abdomen long and attenuated ; nine segments, last segment small, cylindrical in ¢ ; fusciform in 9 ; eighth and ninth segments very small. Legs long, very slender ; tibiae with no spines or spurs. Wings minutely hairy ; third longitudinal forked, upper branch nearly at right angles, joining second vein near its tip ; fourth longitudinal vein emitting a transverse veinlet which joins the third, forked imme- diately after this; sixth and seventh do not reach the border. Areolets fourteen. ‘These gnats appear almost all the year, and are found in shady and damp places ; they are often met with in winter, especially on mild days, even when snow is on the ground. Walker says they “are allied to Dixa and 77richocera,” but the neuration is entirely distinct from both. od ge ot soe | Macrocera, K\t., Mg. GENUS Bolitophila, Mg. = i pees § There are four species in the genus, two of which are found in England and two in Russia. B. cinerea, Mg. This is a grayish-black gnat, with testaceous palpi. Pectus also testaceous, and so are the antenne at the base. Legs yellowish, tibiz and tarsi blackish. Wings with a small gray spot on the costa THE MV CB LOPREALELD A 147 at the tip of the radial vein. Length 2} to 3 lin. Common in most places. (B. maculipennis, Wik. B. fusca, Mg. =- M. hybrida, Mg. | Messala Saundersii, Curt. This is a larger species than the former. Schiner describes it as brown, Walker as ferruginous; the only one I have seen is brownish. Thorax with three dark longitudinal stripes. Head brown, palpi pale or yellowish. Antennz brown, pale at the base. F1G. 31.—Bolitophila fusca. A=base of antenna enlarged. Legs yellow, tibiz and tarsi brown. Wings pale, grayish-yellow in colour, with a gray spot at the tip of the prebrachial areolet, and a large brown spot by the costa at the tip of the second longitudinal vein. ‘This is a rarer species than the former, and may be known by its lighter colour and the presence of the spots (2) on the wings. The habits of the larvz of this genus seem to resemble those of Mycetophila. “The larva spins a cocoon which remains on the sur- face of the ground, or among the fragments of the decayed fungus.” SECTION 7.—Mycetobine. Antenne 17-jointed, not long. Brachial vein long. Sub-costal rudimentary, third, fourth and fifth veins forked. * Pro. Ent. Soc. Phil., 1862, p. 13, reprint. Osten-Sacken. 10—2 148 AN ACCOUNT OF BRITISH FLIES. GENuS JZycetobia, Mg. Body rather short. Head round, flatabove. Eyes reniform. Pro- boscis and palpi short ; the latter is 4-jointed, first joint small, second long, third small and fourth long. Antenne 17-jointed, end joint very small. Abdomen composed of seven segments. Legs stout; tibice without spines, very short spurs. Wings broad, small hairs ; brachial and cubital (third) forming a sessile fork ; fourth longitudinal vein forked near the tip of the wing, and emerging from the pobrachial transverse veinlet; fifth forked, forming the pree- and pobrachials ; sixth and seventh incomplete. Areolets thirteen, viz., the humeral, radical, sub-costal, radial, prebrachial united to the pobrachial, cubital, sub-apical, anal, sub-anal, sub-axillary, axillary and three externo- medials. \ \ FIG. 32.—Mycetobia pallipes. a=posterior tibia and spurs ; b=last tarsal joint and ungues ; c=wing; d=palpus. The larvze feed on fungi and rotten wood. Macquart reared them from larvee found in the detritus of elm wood. ‘The only species of this genus inhabits woods, and may be taken at rest on tree stems, especially decayed ones, and those covered by lichens. M, patlipes, Mg. Black. Abdomen brown. Head and antenne black ; palpi yellow. Legs yellowish, tarsi brown. Wings limpid, black veins. Spurs yellow. Inhabits decayed tree trunks. Mycetobia, Mg. Genus Ditomvia, Wtz.= ; Symmerus, Wik. Body slender. Head roundish, small. Proboscis and palpi short ; first joint small, oval; second long, third and fourth small. Antenne 17-jointed, slender, compressed; first joint cyathiform; second transverse, the rest ovate-cylindrical ; the seventeenth small. Eyes roundish ; ocelli three, central one small. Thorax oval. Abdomen seven segments, long, compressed, widened at the tip in the ?, linear in the ¢. Legs long; posterior tibiae longer than tarsi; tibize armed by short spines and fairly long spurs. Wings hairy, fairly LLL, NEV CLE OLTTME LT) As: 149 broad ; first longitudinal rudimentary ; second longitudinal not very long ; upper fork of third passes much beyond the second, hind fork FIG. 33.—Wing of Ditomya fasczata. ending at the tip of the wing ; fourth arising from the third nearer the apex than the connection with the third and second; the sixth (anal vein) extends to the border. The larve live in Boleti. ‘This genus seems to be doubtfully represented in Britain. There are only two species, one of which is found in England. D. fasciata, Mg. = trifasciata, Wz. Yellow. Thorax with three brown stripes, the lateral pair shortened in front; a brown spot on the sides. Abdomen blackish-brown, sutures and genitalia light brownish-yellow. Palpi brownish, the last joint shorter than the other three. Antenne brown, yellow at the base. Legs brownish, the femora yellow ; tarsi brown. Wings grayish, with three brownish bands (transverse), one at the apex, one in the centre, the third towards the base.- Length 2 to 3 lin. ‘Mycetobia, Mg. Genus Plesiastina, Wtz. => Symmerus, Wk. | Ditomyta, Wik. Head, thorax, and abdomen and legs as in Ditomyia; palpi 4-jointed, the first joint small. Antenne r7-jointed, basal joint smaller than the others ; the last joint small. Eyes reniform ; ocelli three, the middle one small. Wings as in Détomyza. The larvee live in Boleti and rotten wood. PREF A Ceroplatus flavus, Zett. , \ P. vittata, Wik.* Testaceous. Palpi tawny ; antennz brown, testaceous at the base. ‘Thorax with three brown stripes, the middle one longest, broadest ia front, Abdomen with a brown dorsal stripe. Legs yellowish, tarsi brown. Wings grayish-brown. This is a rare insect. * T believe wittata, Wik., to be synonymous with aznelata, Mg., and therefore the same as Zetterstedt’s Ceroplatus flavus. 150 AN ACCOUNT OF BRITISH FLIES. Section 8.—Deradocidinea. Body bare, short. Head round, flat above, hairy in front. Pro- boscis short; palpi 4-jointed, slender. Antennz 17-jointed, stout, cylindrical, last joint small. Eyes reniform. Ocelli three, the central one not much smaller than the others. Thorax nearly round, Fic. 34.—Wing and palpus of Déadocidia ferruginosa. scutellum small. Abdomen 7-ringed, cylindrical. Legs stout, pubescent ; tibiz slender, armed with spurs at the tip; posterior tibiz with slender spurs. Wings broad, hairy, parallel in repose ; first longitudinal vein very small ; second longitudinal vein springing from the base of the first and ending befcre the tip of the wing ; third longitudinal vein simple ; fourth forked, springing from a transverse angular veinlet, sixth reaches the border. Metamorphosis un- known. Macroneura, Macq. GENUS Dradocidta, Ruthé = { at Sctara, Zett. ‘\ This is the only genus in this section. D. flavicans, Ruthé. D. ferruginosa, Mg. => D. Winthemi, Macq. S. testacea, Zett. Tawny. Thorax with three brown stripes. Abdomen yellow or yellowish-brown ; apex dark. Head and antenne brown, basal joints, palpi and proboscis yellow. Legs yellow, brownish tarsi ; posterior tibic longer than tarsi. Wings grayish, with brownish veins and gray hairs. Length 14 to 2 lin. This seems a doubtful British species. Walker says it has been found by Mr. Haliday at Killarney. Literature on the Mycetophilide : 1. Beitrage zur Naturgeschichte d. Insecten. Sitzburger d. Wien. Acad., vol. vii. Heeger. 2. Annales des Sci. Nat., 2 s., vols. xii. and xii. Mémoire sur les métamor. d. plusieurs larves fungivores, etc. Dufour. 3. Bemerkungen u. ein. Arten. Zweif. Gattungen. AZacrocera, etc. Isis, 1830. Stannius. 10, Tt. 12. THE MV CE LOPRALIEID A: 151 Mémotre sur un insecte d. genre Bolitophila. An. d.Sc. Nat., tere s., 1827, vol.x. Guérin. Révision et Monographie de genre Ceroplatus. An. d. Sc. Nat., 2 s., vol. xi. Dufour. Journal Roy. Agricultural Society, vol. x. (Scvara). Curtis. Farm Insects. Curtis (p. 460). Der Kopaliner Heerwurm und die aus ihm hervorgehende S. militarts. Briinn, 1868. Max. Nowicki. Der Zoologische Garten, Frankfort a. M., 1868-71-79 (Articles on Heerwurm). Beling. Characters of the Larvae of Mycetophilide. Pro. Ent. Soc. of Philadelphia, 1862 (reprint 1886). Osten-Sacken. Beitrage zu einer Monograp. der Sciarinen. Wien, 1867. Winnertz. Dipterologische Aanteckeningen. N.1. Tijdschr. voor. Ent. 2de. s., Dec. ii. and ili., pp. 224-236. Van der Wulp. Ento. Hor. Rossland, T. xxiii., 1889. Mono. Phronza. Dziedzcki. Lin. Ent., vill., 1853. Zygoneura. Winnertz. . Entom. Zeit. v. Stettin, 1846-52. Winnertz. eeVetiird:.Z00l..bot..Ges., xl, .1o03s ;Wainnertz. peeroj.ebidskrail., 1640. -staecer. . Dipt. du Nord. Macquart. Ins. Brit. Diptera, 1851. Haliday (Zpzdapus), (Azana). . System. Beschr., i., 1818. Meigen. . Illiger’s Magaz., ii., 1803. Meigen. . Hist. Nat. d. Ins. et Crust., xiv., 1804 (Asindulum). Latreille . Brit. Ent., 365, 1831 (Leptomorphus). Curtis. CAGE ahi Var. THE BIBIONIDZ. TuHIs is a small family of usually dark flies. ‘The body broad, fairly large, 7-9 segments. Prothorax conspicuous ; scutum of meso- thorax undivided. Wings broad, with no discal areolet. Antennz seldom longer than head in both sexes ; thick, cylindrical, moniliform ; composed of from 8 to 12 joints. Palpi 3 to 5 jointed (apparently only one large joint in Scafopse). Eyes large, round or reniform, often hairy ; contiguous in ¢,smallin 9. Ocelli three. ‘egs short ; tarsi armed with ¢hree pulvil/?; tibize having often large thick spurs. The following are synonymous with Bzdionide. Libionides, Westwood. ipsa muscaformes, Mg. Libionide = - Bibionites, Newne. Flirteides, Bilb., Zett. Scatopsides, Zett. The Bibionidz are divided in two sections, and the genera tabulate as follows : A. Scarorsin&. Posterior basal cell wanting. Anterior tibiz of usual shape. Metatarsus of the hind legs shorter than the rest of the tarsal joints together. Legs moderately thick. Third longitudinal not forked - - = Scatopse. Anterior tibiz of usual shape. Metatarsus of the hind legs as long or longer than the rest of the tarsal joints together. Legs slender =