152 



DIPTERA OF MINNESOTA. 



Very fine tobacco dust sifted into the hair on the back, and where- 

 ever it will find lodgment, and the above wash applied to other parts 

 which v/ill not hold the dust, will obtain good results. Prof. J. 

 B. Smith of New Jersey, reports success with this treatment, and 

 says that tobacco dust is fatal to the horn fly, if the fly stays on the 

 back of the animal where the dust has been scattered, long enough 

 to bite. It is said by some to be one of the few things which will 

 repel the stable fly. 



A device, which we have never seen, to be arranged in a door- 

 way of a stable, or, with certain modifications, in a pasture, has 

 been extensively advertised in the papers. It consists practically 

 of a passageway in which brushes are so arranged that when a cow 

 enters the stable, the flies on the back or flank are brushed off, and 

 rise into a glass dome above, attracted by the light. This consti- 

 tutes a trap, for they never go down, and can bekilled there or allowed 

 to die. It has been, claimed that when some such contrivance is placed 

 in a pasture, cows soon learn that they can obtain relief by passing 

 through it. 



THE BLOW FLY OR MEAT FLY. 

 Calliphora vomitoria, Linne. 



Fig. 147. Blow Fly, enlarged. Lugger. 



