DIPTERA. 67 
fore-legs, and their noses nearly in contact with the ground. 
When these poor beasts are in the open country, they are observed 
assembled with their nostrils against each other and very near 
the ground, so that those which occupy the outside are alone 
exposed. The Cephalemia ovis (Fig. 49) has a less hairy head, 


Fig, 49.—Cephalemia ovis. 
but larger in proportion to the size of its body, than the Gad-fiy 
(Gstrus equi). Its face is reddish, its forehead brown with pur- 
ple bars, its eyes of a dark and changing green, its antenne black, 
its thorax sometimes grey, sometimes brown, bristling with small 
black tubercles, the abdomen white, spotted with brown or black, 
and the wings hyaline. 
The Cephalemia (Cistrus) ovis is to be found in Europe, Arabia, 
Persia, and in the East Indies. It lays its eggs on the edges of 
the animal’s nostrils, and the larva lives in the frontal and maxil- 
lary sinuses. It is a whitish worm, having a black transverse 
band on each of its segments. Its head is armed with two horny 
black hooks, parallel, and capable of being moved up and down 
and laterally. Underneath, each segment of the body has several 
rows of tubercles of nearly spherical form, surmounted by small 
bristles having reddish points, and all of them bent backwards. 
“These points,’ says M. Joly, ‘probably serve to facilitate the 
F 2 

