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Show 284 . INSECTA. . E . talis Fa b. -Milesia, Lat. PIPIZA, Meig.-Psilota, Melg.- rzs ' . legs are n1ere ly Somewhat larger than the Where the posterior d semi-elliptical and rounded bd is depresse , others, and the a omen t These Insects are closely Th e es are pubescen • . ( ) at the end. e Y . 1 1 to Chrysogaster, Me1g. 1 allied to Syrphus, and parucu ar y BRAcHYOPA, Hoff. Meig. the receding subgenera by the wings, Distinguished fr~m all be pond the abdomen. These Diptera which extend conslde~:b~y ~d appear to lead to Rhingia, the last closely resemble the MI esice, ad' to Meigen the seta of the an-f this tribe. Accor mg . . subgen.u s o• ' 1 could discover those hau·s 1n any 1 at base but never . tennce 1s p1 ose ' . d T th'ls subgenus the same naturahst • 5 I obtame · 0 1 of the spec1m~n. . f F b . 'us which most certainly be ongs refers the Osctms olwce o a rtcl ' to the Muscides(2). h' h have hitherto spoken, the pro-h S . bidce of w tc we . . 1' In t ose yt P d d thorax and the pro1ectton 1orms boscis is shorter tha.n the hea a:m We 'now proceed to others in a short and perpendic~lar ::st:l l~nger and almost linear, and the whic~ that ~rob.oscis /~h:v~ec;d ~s proportionally more elongated, anterior proJection o fa pointed rostrum. These and directed forwards in th~ manne.r o bent on the body, and in . h · 'ngs whtch are meum Insects, m t elr Wl ' 1 ble the Brachyopce and the form of their antennce, close y resem Milesice. The thighs are simple. They form the RHINGIA, Scop. Fab. Meig.(S) The genus PELEcooERA, Hoffmanseg, Figured by Meigen, is unknown to us, b ut I· t ·t s e asily dl istidnbgu isthhe· ed from all those whose antenuce are shorter than the lea y (1) Idem, genera Pipiza and Psilota. (2) See Meigen. (3) Fab., Lat., Meig., &c. DIPTERA. 285 seta of the same organs which is short, thick, slightly silky, cylindrical, and divided into three joints, the last of which is somewhat the longest. The palette almost forms a reversed triangle. The sucker of all the remaining Athericera oonsists of but two setre, the superior representing the labrum, and the inferior the ligula. They form three other small tribes which will correspond to the genera fEstrus and Conops of Linnreus, and to the Musca, Fab. as originally composed. As Stomoxys and Bucentes are connected with this last genus, we will begin with the tribe of the ffisTRIDEs consisting of the genus £EsTRus, Lin. Which is very distinct, as in place of the mouth '"e find but three tubercles, or slight rudiments of the proboscis and palpi. These Insects resemble large and densely pilose flies, and their hairs are frequently coloured in bands like those of the Bambi. Their antennce are very short; each one is inserted in a fossula over the front, and terminated by a rounded palette with a simple seta on the back near its origin. Their wings are usually remote; the alulce are large and conceal the halteres. The tarsi are terminated by two hooks and two pellets. These Insects are rarely found in their perfect state, the time of their appearance and the localities they inhabit being very limited. As they deposit their eggs on the body of various herbivorous quadrupeds, it is in woods and pastures that we must look for them . . Each species of CEstrus is usually a parasite of one same species of some mammiferous animal, and selects for the location of its eggs the only part of its body that is suitable for its larvce, whether they are to remain there, or pass from thence to the spot suited for their development • . The Ox, Horse, Ass, Rein-deer, Stag, Antelope, Camel, Sheep and Hare are the only quadrupeds yet known, which are subject to be inhabited by the larvce of the CEstri. They seem to have an extraordinary dread of the Insect when it is buzzing abot~.t them for the purpose of depositing its eggs. The domicil of the larvce is of three kinds; we may distinguish them by the names of cutaneous, cervical, and gastric, as some live |
