168 THE GAD- OR BREEZE-FLIES. 



we know. In our southern counties the ^^ Green-head'^ 

 {TahaiiiLS lineola Fab.) has a very bad reputation and further 

 south in the Mississippi valley it is sometimes impossible to 

 workhorses in midsummer without a protecting covering. In 

 fact cases are on record that horses fastened to a tree or a 

 fence were bitten to death. This fly is illustrated in fig. 138, 



Fig. 138. — Greeu-head. Greatly enlarged. Original. 



"T/je Black Breeze-fjy {Tahanus atratus Fab.), though found 

 in Minnesota, is not common, hence causes less trouble to 

 cattle, which it prefers to horses. Itslargelarva isfoundunder 

 stones in water, where it feeds upon other aquatic animals. 

 The most common of our breeze-flies is illustrated in fig. 139, 

 plate XIII . It is '^Rein wardt's Breeze-Hy' ' ( Tahanus reimoardtH 

 Wied.). This fly, less blood-thirsty than the two mentioned 

 above, is found in immense numbers in our prairie region. 

 It sometimes gathers in the small railway stations in such 

 numbers oujthe window-panes that no light can fall through 

 them, and the writer counted upon one window, and below 

 it upon the bench, the astonishing number of 2117 flies. 

 Why thcA' should remain and die in such places is difficult to 

 explain; at all events these rooms acted as traps, and the 

 flies had not sense enough to escape by the open door, but 

 battered their heads against the glass in their A-ain efforts 

 to force their way out. The larger breeze- or gad-flies attack 

 onh^ larger domesticated animals, such as horses and cattle. 

 The genus C/wf/sajh^ is distinguished from JaJxHias by posses- 

 sing three simple eyes, which are readily seen on the top of 

 the head. The scientific name is derived from the beautiful 

 golden-yellow eyes, with purple lines and spots, which these 



