118 INSECTS AFFECTING DOMESTIC ANIMALS. 
at right angles, but approaching it, approximately an angle of 60° from the abdomen. 
The legs are spread out widely, and the beak, inserted beneath the skin of the animal, 
is held in nearly a perpendicular position, approaching that in figure 59, c. 
The fly before inserting its beak has worked its way through close to the skin. 
While feeding, however, the hairs which can be seen over its body do not seem to 
interfere with its speedy flight when alarmed, for at a fling of the tail or an impa- 
tient turn of the head the flies instantly rise in a cloud for a foot or two, returning 
again as quickly and resuming their former positions. 
Fic. 59.—_Hematobia serrata: a, head of female, front view; b, head of male, front view; c, bead from 
side—all enlarged (from Insect Life). 
The horns are not their only resting places, for with the horns black for 2 inches 
above their base we have seen the flies toward nightfall settle in vast numbers upon 
the back between the head and foreshoulders, where they can be reached by neither 
tail or head. When feeding they are found over the back and flanks and on the legs. 
During a rain storm they flock beneath the belly. When the animal is lying down 
a favorite place of attack seems to be under the thigh and back belly, around the 
bag. With certain animals the dewlap seems to be badly attacked, while with others 
this portion of the body is about exempt. Certain cattle, again, will be covered with 
flies and will lose condition rapidly, while others are troubled but slightly. 
Fia. 60.—Haematobia serrata: cow horn showing band of resting flies—reduced (from Insect Life). 
On the horns the flies settle thickly near the base, often forming a complete band 
for a distance of 2 inches or more. (See fig. 60.) They seem to prefer the concave 
side to the convex side of the curve of the horn, probably for the reason that the 
cow can not scrape them off so readily, and one cow was noticed in which they 
reached nearly to the tip of the horn on the concave side of the curve only. 
