232 DIPTERA. 



FAMILY XXXIII. Platypezidce. 



Head round, as broad, or broader, than the thorax ; antennae 

 with a terminal bristle; eyes contiguous, at least in the male; 

 ocelli present ; abdomen and legs short, the latter stout ; the larvae 

 inhabit fungi. 



The Platypezidce frequent shady places under hedges or near 

 water. One genus, Callomyia, Meig., includes very beautiful species, 

 which, however, are not very abundant. They are black flies, 

 about one-sixth of an inch in length, and the females are marked 

 with silvery-white and orange-yellow. 



FAMILY XXXIV. CEstridce. 



Head large and prominent, about as broad as the thorax ; an- 

 tennae short, third joint with a terminal bristle ; eyes rather small, 

 not contiguous ; ocelli present ; abdomen short ; legs long ; larvae 

 parasitic on various species of Mammalia. 



The Bot-Flies are not remarkable in their perfect state, but 

 are interesting from the habits of the larvae. The principal Euro- 

 pean genera are as follows : Gastrophilus, Leach (larvae in the 

 stomach of the horse) ; (Estrus, Linn, (larvae in the frontal sinus 

 of sheep, buffaloes, etc.) ; Pharyngomyia, Schin., and Cephenomyia, 

 Latr. (larvae inhabiting the nasal and pharyngeal cavities of deer) ; 

 Hypoderma, Clark (larvae in swellings called " bots " on the skin of 

 oxen, etc.) ; and (Estromyia, Brauer (larvae supposed to be parasitic 

 on the chamois). 



CEstridce do not always confine their attacks to the same species 

 or even the same groups of animals, and in tropical countries man 

 himself is sometimes attacked by them, though the worst Dipterous 

 parasites on man are Muscidce of the genus Sarcophila. It has 

 occasionally happened, however, even in Europe, that men have 

 been attacked by one or other of the indigenous species of CEstrus ; 

 but such cases are extremely rare. Even the smallest animals are 

 liable to be infested by them. At a recent meeting of the Ento- 

 mological Society, Mr. C. 0. Waterhouse exhibited the larva of an 

 CEstrus which measured nearly an inch and a half in length, and 

 was found in the body of a common mouse from Peru, of which 

 it occupied almost the whole of one side. He also stated that 

 several other mammals received in the same collection from Peru 

 were found to be similarly affected. 1 



1 Proceedings of the Entomological Society of London, 1881, pp. xxii 

 and xxiii. 



