DIl'TEltA. 365 



In a '* Memoire pour servir a I'Histoire du gome Ocyptera," — 

 Ann. dcs Sc. Nat., X, 248, 1 1— M. Leon Dufoiir has described the 

 larv<« of two species; the O. cnssidd- and tlie O. bicolor. That of 

 the first species lives in the visceral cavity of the Cassida bicolor, and 

 that of the second in the same situation in the Pentatoma nrisea. 

 Both of them feed exchisively on the epij)loon or corps graisseux of 

 their hosts. Their body is oblong, soft, whitish, perfectly glabrous, 

 rugose and contractile. 



Its anterior extremity presents two mammillae, each furnished with 

 two little cylindrical bodies terminated in the manner of a button 

 umbilicated in the centre, and with as many strong, horny pieces, 

 each i)rovided exteriorly with one or two large hooks, which givea 

 them the appearance of being forked, and tlieir convex sides placed 

 back to back. From the figure given by this naturalist, it would 

 seem that there is one for each raammillcie, and that they are internal. 

 He considers them as mandibles, and the species of palpi, of which 

 we have just spoken, tlie disk of which is perforated in the centre, 

 as a sort of foot-palpi, acting like a cup or organs of touch. The 

 body of these larvae terminates by a sort of siplion, about one-third 

 as long as the l)ody, of a more solid consistence and constant form, that 

 Ijecomes gradually narrowed, and with the appearance of two hooks 

 at the end. The posterior extremity of this siphon occupying one of 

 the metathoracic stigmata, and being in contact Avith the air, enables 

 the larva to respire. Neither antennas nor eyes can be perceived. 

 It is in this same abode that the larvae passes into the state of a pupa. 

 The latter is ovoid, exhibits no trace of annuli, and presents at one 

 extremity four (O. cassidce') or six (O. bicolor) tubercles. It 

 leaves its domicil previously to attaining its perfect condition, some- 

 times while the Insect in which the larva resided is still living, and 

 sometimes at the expense of its life. These larvae have two salivary 

 vessels, four biliary vessels, and tubular tracheae without a nacred 

 aspect, or transverse striae, arranged in two principal trunks, and 

 giving off numerous ramifying branches. These trunks appear to 

 empty into a unique orifice at the base of the caudal siphon. The 

 alimentary canal is about four times the length of the body, and 

 presents a capillary esophagus, a crop resembling a turbinated bowl 

 of a pipe, which insensibly degenerates into a tubular, doubled 

 stomach, followed by a flexuous intestine, a slightly apparent rectum, 

 and terminated by an oblong caecum *. 



In the following subgenus, or 



Mklanophoba, Meig., 

 Which he suppresses and unites to Tachina, the antennae are much 

 shorter, their extremity, when they are inclined, scarcely extending 

 beyond half the length of the face of the head. The most exterior of 

 the two complete cells, which terminate the wing, is much more pro- 

 longed posteriorly than the other, and the internal angle of its extre- 

 mity is obtuse f. 



* See Meigcn, and the Encyc. Method., artirle Ocypthre. 

 t Lat., Gener., Crust, et Insect., IV, 346. 



