them. This can not come from any pain caused by the placing of the 

 eggs on the animals, but must be from an instinctive dread of the 

 insect, and is analogous to the similar frantic actions of the liorse when 

 approached by the throat hot. 



The injury to fattening range cattle in the spring is due very largely 

 to the annoj^ance occasioned by the presence of the fly. A Texas 

 correspondent, Mr. George W. Holstein, calls attention to this fact as 

 follows: "A cow quietly grazing will suddenly spring forward, throw 

 up her tail, and make for the nearest water at a headlong gait. Seem- 

 ingly deprived at the moment of every instinct except the desire to 

 escape, she will rush over a high bluff if in the way, often being killed 



Fig. b.—Hypoderma lincata: a, eggs attached to hair; 6, c, d, dorsal, ventral, and lateral view of egg; 

 f, eiiibryonic or first larva, as seen in egg; /, g, mouth parts of same enlarged; fi, anal segments of 

 same still more enlarged (from Insect Life). 



by the fail. This, with miring in water holes and the fact that cattle 

 are prevented from feeding, causes the loss." 



As observed in the act of egg-laying, the flies approach the cattle 

 very swiftly, being almost too quick in flight to be observed except 

 at the very moment of placing the eggs. The eggs are fastened to 

 the hairs, in the examples received here, usually four to six together. 

 The structure of the lower portion of the egg is of such a nature that 

 it clasps the hair almost entirely and forms a very firm and strong 

 attachment. The peculiar shape of the egg is shown in the illustra- 

 tion (fig. 5). In length it measures about two millimeters, and is of 

 a dull yellowish-white color. The ovipositor, extended as in the act 

 of placing the egg, is represented in fig. 6. 



The eggs once in position, the larva^ probably ratlier than the eggs, 

 are carried into the mouth by means of the licking of the leg and the 



