152 



The Two-winged Flies 



is a yellowish winged species common on owls, some hawks, and the ruffed 

 grouse. Swallows are often infested, and I have taken bird-ticks from half 

 a dozen other kinds of birds. A careful .search for these curious in.sects 

 will certainly make known numerous new species. 



Fig. 501. — A horse-tick or forcst-r.y, Hippoboscn eqiiiim. (.After Lugger; natural 



length i to § inch.) 



The genus Lipoptena includes a few known species found on mammals 

 which are winged for awhile, but later cast or bite off the wings. They 

 probably fly about in their search for a host, after finding which they remove 

 their wings and remain for the rest of their life on this host individual. Lip- 

 optena cervi is a species found on deer. 



Fig. 504. 



'•"'^■- 5°-- Fig. 503. fig. 503. B.-it-tick. Xycleribij sp. 



Fig. 502. — Sheep-tick, Melophagiis mini<s. Nat. size J in. 



Fig. 504. — .\ bec-lou.sc, Bniula sp. (After Sharp; much enlarged.) 



The bat-ticks, Nycteribiida" (Fig. 503), are curious long-legged, wingless, 

 small spider-like creatures about 1 inch long or less, which look as if the 



