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Show 276 INSECTA. But few of the Athericera are carnivorous in their perfect state. They are generally found on trees, leaves and flowers, and sometimes on the freces of animals. This family comprises the genera Conops and (Estrus of Linnreus, and most of the species of his genus Musca. We must naturally separate from the last those numerous species in which the sucker is composed of four pieces, and not of two, as in all the other Athericera. They will form our first tribe, that of the SYRPIIIDJE. Their proboscis is always long, membranous, geniculate near the base, terminated by two large lips, and encloses the sucker in a superior groove. The upper piece of this sucker, which is inserted near the elbow, is broad, arched and emarginated at i~s extremity; the three others are linear and pointed, or setaceous; to each of the two lateral ones, representing the maxillre, is annexed a little membranous, narrow palpus, Rlightly widened and rounded at the end; the inferior seta is analogous to the ligula. The head is hemispherical, and mostly occupied by the eyes, that of the males particularly. Its anterior extremity is ft·equently prolonged in the manner of a snout or rostrum, receiving the proboscis underneath when it is doubled. Several species resemble Bombi and other Wasps. M. Lepeletier de Saint-Fargeau has communicated to the Academie Royale des Sciences, some curious observations on the unnatural coition of some of these Insects, or to use his own words, on their '' marriages adulterins,'' the result of which, however, he was unable to follow. This tribe will comprise but the single genus SYRPHUS. A first general division will consist of all those species in which the proooscis is shorter than the head and thorax. The snout, in those where it is distinct, is perpendicular and short. Then come Syrphidre, in which the fore-part of the head, a little above the superior margin of the oral cavity, or near the origin of the snout, presents a prominence. DIPTERA. 277 At the beginning of these species we will place those whose an-tennre, always shorter than the head, are furnished with 1 seta. a p umous Their body is short, and frequently pilose, and the wings are dis-tant. At the first glance these Insects resemble Bomb' d I f I . . 1, an as the ·ra rvhre o severa mhablt the nests of those H ymenoptera, 1· t seems as 1 t e autho. r of nature clothed them in a 8 •t ml'I ar manner, m· order that they m1ght penetrate into their habitations without da Th e S yrp h1'd re compose three subgenera. nger. VoLUOELLA, Geoff. Lat. Meig. Fab. Where the third joint of the antennre or the palette is oblong· its contour forms a curvilinear and elongated triangle. ' V. myst~~~a; Musca mystacea, L.; V. bourdon, De Geer, Jnse~ t. VI, Vln, 2. Black, and densely pilose; thorax and extrem. Ity of the abdomen covered with fulvous hairs; origin of the wmgs ful vous. The larva inhabits the nests of Bambi Its body . 'd d from b t . · 1s Wl ene ~ ore p~ster10rly, is transversely rugose, has little points on the s_Ides, SlX membranous radiating threads at the posterior extrem~ty, and presents above, two stigmata and six pairs of ~amnullre, each furnished with three long hooks which enable It to crawl. Here also comes the I M. a zones, Geoff.; Syrphus inania, Fab.,· Panz Faun f nls ect . G·e i ·m ., II' 6. Et· ght h·n es long; but slightly., pilose·· u vous; he~d ~ellow; two black bands on the abdomen. It: larva also hves In the nest of the Bambi( I). SERIOOMYIA, Meig. Lat.-Syrphus, Fab. V\'here the palette of the antennre is semi-orbicular(2). (1) Fo1· the othe · (2) Th r specles, see Lat., Meig., Fab. and }'allen. e same authors. |
