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Show 308 INSECTA. . 11 that which comes after the cubital, stilet. The first termmal ce ~ ~ ms a narrow, elongated, and trun-is almost closed at the end, 01 t~ ubgenus belongs to the division cated triangle. I suspect that lS s of the Dolichopoda( 1 ). f e furnished with hairs; the first h 'd of the ace ar In others, t e Sl es. h slender than the following ones, . . f 1 • t nre IS muc more JOlnt o t 1en· an en h t thickened at the end; the two fol-almost cylindrical, and somew a b lowing ones form a small rounded clu • LoNonoPTERA, Meig.-Dipsa, Fall. . laced on an eminence. The wings are lollg Where the ocelh are P beyond their base; the third Ion-and exhibit no transverse nervurte . r margin is bifurcated. This . 1 . t't•om the ex er1o , . gitudma nervut e, f th Dolichopoda, near which Me1gen subgenus is far removed rom e has placed it(2). S t ides is thicker and less oblong, Th body of the other ca omyz Fl e h' more to the form of that of the common y. approac mg One single subgenus, or the HELEO:MYZA, Fall., Presents mustachios(3). . ed from the last of the division by Two other subgenera are 1 emov the pilose or plumous setce of their antenna::. DnYOMYZA, Fall. Meig. Where the face is concave beneath the antennce, and terminates . . t eems to belong to ( 1) Idem. For the genus Tetanops, whlch m some respec s s this division, see that of the Carpophila. {2) See Meigen. L ) of De Geer, wl1ich (3) Fall, Dipt. ~ the Mouclte des latrines (Musca serrata, • . in the seta of is referred by Fallen to this subgenus, differs from t~le other spe~les ore arbicu}ar. the antennz, which is simple. The pa.le~te also lS largel' ann :very common This Insect, which bas a cinereous body Wlth a fulvous abdome '. m",.gin of the d d t ti f the exter1or ... in the interior of our houses. The set~ ~n en a ons o other Scatomyzides. win~"S fol'ffi no peculiar character-It lS common to seve~~l. tl first edition of Theo MouclLe bossue of De Geer-I nse ct. , 'rr ' .u. , 5-quoteu m le t · •·ly is not this work, whose larva, that feeds on Aphides, has two horns pos erlo • an Oscina, but rather a. Heleomyza. IHPTERA. 309 inferiorly, or at the oral cavity, by a short, truncated snout, as in Scatophaga, and in most of the Dolichocera(l). SAI'ROMYzA, Fall. Meig. Where the face is straight, and does not project inferiorly(2). The last of the Scatomyzides have the seta of the antennce simple( 3); these organs are always very short, distant, and straight, with the last joint semi-ovoid or forming a short triangle obtuse at the end. These Insects are very small, almost glabrous, black or cinet·eous, and more or less varied with yellow; the legs are strong and the eyes large. The summit of the head is flat and frequently presents, at its posterior extremity, a triangular brown space, on which are placed the ocelli. The two ordinary transverse nervures of the wings are approximated near the middle. These Diptera are found on flowers. Several of the larvre attack the interior of different plants, and some of them are very injurious to the agriculturist by destroying various cerealia previous to their fructification. Those of one species- Musca frit., L.-in Sweden sometimes destroy the tenth of the crop of barley, the total loss thereby occasioned being estimated at one hundred thousand golden ducats. The larvre of some other species-the Oscina pumilionis, and O.lineata, Fab.-are also highly noxious. For further details on those Insects which attack our cerealia, see the Memoir of the late M. Olivier( 4). These Scatomyzides compose our genus OscxNis, Lat. Fa.b. To which we refer the Chlorops of Meigen. A species that I have received from Germany under the name of brevipermis, might however form a separate subgequs on a~count of the seta of its antennre, which is thick, almost in the form of a stilet, and geniculate. The anterior and superior extremity of the head is sometimes truncated, and sometimes pointed. Another dipterous Insect which was also (1) Meigen. (2) Meia-en. (3) It is thickened nt its base. ( 4) Certain species in which the seta of the antenna: is plumous, and refet·red by him to the genus Tephritil, are perhaps Sapromyz;e. |