DIPTERA. G33 



(iiimnosoma, Meig;., has the abdomen vesicular, -wiUi indistinct articulations, and the autennai as long as 

 the liead. 



Cistogaater, Latr., Las the abdomen similar, but the antennae much shorter. 



Phasia, Meif!;., has the abdomen very flat and semicirciUar, and the tibiai but slig;htly bristly. 



Tricltiopoda^ Latr., has the abdomen flat but oblong, and the bind tibia; with a row of lamelliform bristles. 



Sometimes the face has two rows of long; bristles, Hke moustaches, two being- larger than tht^ rest. 



The three following have the wings vibratile, and the abdomen narrow and elongate; the anCennEe are not 

 shorter than the face. 



Lophosia, Meig., has the last joint of the antenna; forming a large triangular palette. 



Ocyptera, Meig,, has the third joint of the antenna; seldom much larger than the preceding, and forming a linear 

 or oblong square. M. Dufour has observed the transformations of two species ; the larva of 0. caa^'uUc, residing 

 in the visceral cavity of Cassida bicolor, and that of 0. hicolor, in the same cavity of Pentatoma grisea: both these 

 larvoi feed on the fatty matter of the insects they infest ; their bodies are oblong, soft, whitish, perfectly glabrous 

 and contractile, and terminated by a sort of siphon one third of the length of the body, of a more solid consistence, 

 and unchangeable in its form, with two hooks at the tip : the posterior extremity of this siphon, occupying one 

 of the metathoracic spiracles [of the insect infested], and in contact with the air, enables the parasite to respire. 

 Neither antennae nor eyes have been observed. It is in the same situation that the larva changes to the pupa state. 

 This [or rather the old larva skin] is ovoid, without any trace of segments, with several tubercles at one end. It 

 quits its abode before assuming the perfect state, eitlier without destroying the insect, or the larva infested, or 

 after it has killed it. 



Mdanophora, RIeig., has the antennae much shorter; the antennee not extending lo\ver than the middle of the 

 face ; the outer terminal cell is more advanced posteriorly than the inner one. 



The abdomen of the other Creophilas is but little elongated, triangalar ; and the wings are not vibratile. 



PhaniUy Weig., has the abdomen 4-jointed ; the tip being elongated, narrowed, and folded beneath ; the third 

 joint of the antenna is long and linear. 



Xifsta, Meig., lias the abdomen 5- or 6-jointed, and the antennae short, with the last two joints nearly equal ; the 

 hind tibiae are rather curved, compressed, and ciliated. 



Tachi/ta, Fabr., has the abdomen i-jointed, but not recurved at the tip ; the antennae as long, or nearly as long, 

 as the head ; the last joint longer than the preceding. Some of the species, forming a peculiar grou|f, live whilht 

 larv£E in the bodies of diflerent caterpillars, which they destroy. 



We now pass to Creophila which have the seta of the antenme evidently villose or plumose; the third joint 

 always forms an elongated palette, and is longer than the preceding joint. 



Dexia, Meig., has the habit of Ocyptera, with the abdomen narrow and elongated, especially in the males. 



Musca proper {Mesemhrina, Meig.), has the abdomen triangular, the eyes contiguous, or very close together in 

 the males. Here are to be arranged the majority of the tlies of which the larvae feed upon meat, carcases, &c., and 

 others in manure. They have all the form of soft worms ; whitish in colour; destitute of feet ; thickened and truncate 

 at the posterior extremity, and pointed at the other end, where are one or two hooks, with which these larvK gnaw 

 their food, and of which they hasten the corruption. They undergo their changes in a very few days [in the 

 summer] ; the females have the extremity of the body nariowed, and elongated into a tube, to enable them to bury 

 their eggs. Musca vomitoria, Linn., the Common Meat Fly, with the forehead fulvous ; the thorax black, and ab- 

 domen blue, with black marks. It possesses a remarkably tine sense of smelling, and makes a loud buzzing noise, 

 when it enters our houses in order to deposit its eggs on meat. Deceived by the odour of Aram dracunculus 

 w^hcn in flower, it sometimes deposits its eggs in that flower ; when ready to assume the pupa state, it quits its food 

 and descends into the earth, or else undergoes its cliange in some dry and retired situation. M. dutncaUca, Linn., 

 the small Common Domestic Fly, the larva of which lives in moist manure, 



^arcophaga, Meig., ditfers from Musca, by the eyes being wide apart in both sexes ; the eggs in some species 

 are hatched within the abdomen of the parent, as is the case with M. carnaria, Linn, [a very abundant species], 

 which is larger and longer than the Meat Fly : the female deposits her young larvse upon flesh, carcases, and 

 sometimes in the wounds of persons. 



We terminate the Creophila? by some subgenera contrasting with the preceding in the form of the head, situation 

 of the wings, or of their external cells. 



Ackias, Fabr., remarkable for the horn-like elongations of the sides of the head ; with the antennae inserted high 

 in the forehead. 



Idia, Meig., has the front of the head produced into a beak. 



The two following have the terminal cells of the wings extending to the posterior edge; the abdomen is 

 flattened. 



Lispe, Latr., has the body oblong; the antennas nearly as long as the face; and the style plumose. 



Argyrilis, Latr., has the body short ; the abdomen very flat, nearly semicircular ; the head short and broad ; the 

 antenxiL-e very short; with the seta elbowed. 



In all the remaining Muscides, the alulets are small, or nearly olisolete ; the balancers exposed ; and 

 the principal nerves of tlie wings extending to the outer edge of the \\'iiigs, which closes the i:)03terior 

 cells. 



A second general division of the Muscides, that of the Anthomyzides, is composed of species having 



