The Robber Flies. 



4'5 



them pinned, as they were captured, in our college cabinet. 

 These flies delight in the warm sunshine, are very quick 

 on the wing, and so are not easily captured. It is to be 



Fig. 196. 



hoped that they will not become very numerous. If they 

 should, I hardly know how they could be kept from their 

 evil work. Frightening them of catching with a net 

 might be tried, yet these methods would irritate the 



Fig. 197. 



Fig. 



199. 



bees, and need to be tried before they are recommended. 

 I have received specimens of this fly from nearly every 

 Southern State. During the past summer this same fly 

 has been well employed here in Michigan. It has been 

 observed to kill the cabbage butterfly by scores. 



