404 



DIPTERA. 



ground, and there becomes a coarctate pupa, enclosed ■within 

 the old larva skin, and remaining in connection with it by 

 means of four tracheae. 



The genus GastropTdlus has ver}'- small 

 mouth-parts, the deep lying palpi being 

 somewhat spherical, and the 

 proboscis nearly obsolete, 

 while the abdomen is sessile. 

 The species are of inodium 

 size, short and thick, and A'ery hair3^ The female 

 lays her eggs on the horse's hips, or forelegs, b}' 

 which the larvaj are introduced into the stomach. 

 The body of the larva widens posteriori}- ; the 

 mandibles are not visible, and the maxilte con- 

 stitute the so-called mouth-hooks, by which the 

 larva grapples and adheres to the walls of the 

 horse's stomach. The rudimentary antennae are ^'o- 324. 

 indicated by an ocellus-like point. The Horse Bot-fly, Gas- 

 trophilus eqid Fabr. (Fig. 323 ; fig. 324, larva), in its perfect 

 state is pale yellowish, spotted with red, with a graj'ish yellow 

 hirsuties ; the thorax is banded with black, or sometimes. 



though rarety, reddish hairs. The hinder trochanters are 

 hooked in the males, and tuberculated in the females, and the 

 wings are banded with reddish, with two spots at the apex. 

 The larvffi live from May till October, and when fully grown, 

 hang by their mouth-hooks on the edge of the rectum, whence 



