316 



ARTICULATA: INSECT A. 



larva state, to the roots of plants, and in the adult state 

 are very rapacious, seizing and destroying other insects. 



FIG. 407. 



FIG. 408. 



FIG. 409. 



Bot-fly, Ga-sterophilus equi, 

 Linn. 



FIG. 410. 



Bee-fly, Bombylius aqua- Horse-fly, Tabanus lineola, 

 Us, Fabr. Fabr. 



FIG. 411. 



Hessian Fly, Cecidomyia destructor, Asilus, Asilus cestuans. Linn. 



Say. 



Some of the forms of the Diptera. 



Other dipters still are the Bot-flies (CEstriclw)) which in 

 the larva state inhabit various parts of the body of herbiv- 

 orous animals, as horses, cattle, sheep, etc. These flies 

 (Fig. 407) have very short antennae, large head, and the 

 wings covering the balancers ; and the hind-body of the 

 females has a conical tube bent- under the body, and with 

 it they lay their eggs when flying. By biting the parts 

 where the eggs are laid, the horse gets them into his 

 mouth and swallows them. The larvae, by means of 

 hooks, cling to the walls of the stomach till they come to 

 the end of their larval life. Another species (CEstrua 



