238 MONTANA EXPERIMENT STATION. 



Encoptolophus sordidus Burn. THE CLOUDED GRASvSHOPPER 



Often met with in the field and somewhat resembles C. pellucida. 



Acrolophitus hirtipes Say. 



This grasshopper of striking appearance, is uniformly green 

 throughout. It occurs in restricted localities, often in considerable 

 abundance, where in contrast to other sombre-colored grasshoppers, 

 it is quite conspicuous. 



INSECT ENEMIES OF GRASSHOPPERS. 



Grasshoppers have a large number of parasitic enemies and when 

 the grasshoppers as hosts become abundant, their parasites, because 

 of a plentiful supply of food, become numerous also and soon gain 

 the mastery over the hosts. This balancing process is continually 

 active. While we cannot say positively what is the cause of the ap- 

 pearance in Montana of grasshoppers in unusual numbers it is prob- 

 able that parasites as a direct or indirect cause have had a great 

 influence. 



Various correspondents have called our attention to the pre- 

 sence of minute red spots on the bodies of grasshoppers. These red 

 spots are the bodies of a red mite which occurs commonly through- 

 out the state, and which doubtless does some good in preventing the 

 undue increase of grasshoppers. They have often been mistaken for 

 eggs of parasites but there is no reason for confusing the two, since 

 the eggs of parasitic flies are white. 



In every part of the grasshopper affected sections of the state that 

 we visited in the summer of 1903 we found dead bodies of grass- 

 hoppers which contained maggots or larvae of a fly. Some of these 

 were reared in the laboratory to the adult stage and the flies were 

 sent to Dr. L. O. Howard for determination. He reported -the fly 

 to be Sarcophaga cimhicis Townsend. We are unable to state 

 whether this fly killed the grasshopper or whether the larvae were 

 merely feeding as scavengers on the dead bodies of grasshoppers 

 that had died from other causes. 



It was noticeable that a blister beetle or Spanish fly whose 

 scientific name has not yet been determined was very abundant 

 throughout the Yelowstone valley from Columbus eastward. We 



