52 



Fig. 46. Sheep bot Fly. 



Fig. 45. Ox bot Fly Larva. 



Westwood. This little fly, not bigger 

 than the common house fly, is the 

 great obstacle to the exploration of 

 Central Africa. "It is not danger- 

 ous to man, to any wild animals, 

 nor to the pig, the mule, the ass or 

 the goat. But it stings mortally 

 the ox, the horse, the sheep, and 

 the dog, and renders the countries 

 of Central Africa uninhabitable for 

 these valuable animals." 



The genus Tachina, of which Fig. 

 47 represents a species, is parasitic 

 in caterpillars. 



Tachina doryphorce, Riley, feeds on the larvae of the potato 

 beetle. 



The Red-tailed Tachina Fly, Nemoraea leucanice, Kirkp., Fig. 48, is parasitic on 

 the army worm moth, Leucania unipuncta, Haworth. The fly deposits her eggs upon 



the fore part of the body of the worm. Prof. 

 Comstock says " That as many as eighteen eggs 

 are laid on a single worm, but the usual num- 

 ber is about five. These eggs are so ingeniously 

 placed that the worm can by no possibility reach 

 them with its jaws, or get rid of them in any 

 other way. Mr. Howard says that he has 

 searched for hours in a field infested with 

 army worms without finding a single full- 

 grown worm that did not carry one or more 

 upon its back." In Fig. 32, just underneath the fly is 

 shewn the forepart of an army worm exhibiting the placing of the parasitic eggs. 

 Sarcophaga, the Flesh Fly, is one of the viviparous species alluded to before. 



Fig. 49 is an enlarged repre- 

 sentation of Sarcophaga carnaria, 

 Linn. The flesh fly and Fig. 50 

 shows the maggot. 



The female is exceedingly pro- 

 lific. The entomologist, DeGeer, 

 vouching for the development of 

 20,000 larvae in one female. 



These flies sometimes deposit 

 their larvae on living animals, and 

 thus become parasites. 



Prof. Comstock says tha t 

 "specimens of a flesh fly were 

 reared from pupa of the Cotton 

 worm, Aletia Argillacea, Hubner. 

 These proved to be specimens of 

 Sarcophaga Sarracenios, Riley, a probable Ameri- 

 can variety of that wide - spread scavenger, S. 

 Carnaria, a species common to Europe, America, 

 and Australia, certainly and probably else- 

 where to be found, Sarracenim was first de- 

 scribed by Prof. Riley as feeding upon the dead 

 Sarracenia, the pitcher plant. Fig. 51 represents 



Fig. 48. 



Fig. 47. 

 of these 



Fig. 50. 

 Larva of Flesh fly. 



of 



Fig. 49. Flesh Fly. 

 insects to be found in the leaves 

 the insect in all its stages. 



The Anthomyice are to be found 



about flowers, and their larvae live on decaying 



