GENERAL CROP PESTS 



67 



Their larvae destroy grasshopper eggs and thus aid in keeping 

 these pernicious insects in check. This is especially true where 

 both blister beetles and grasshoppers abound. But the benefits 

 derived are really more than counterbalanced by the losses oc- 

 casioned by the rapacity of the beetles ; hence measures should 

 be employed to destroy them when they occur in harmful num- 

 bers. Blister beetles are apt to be found in practically all veg- 

 etable fields. 



The Striped Blister Beetle (Epicauta vittata Fab.). — Before 

 the advent of the Colorado beetle this was considered the most 



Fig. 36. — Striped blister 

 beetle {Epicauta vittata). 

 Female beetle. (Author's il- 

 lustration, U. S. Dept. Agr.) 



Fig. 37.— Three-lined blis- 

 ter beetle (Epicauta lemni- 

 scata). (Author's illustration, 

 U. S. Dept. Agr.) 



destructive potato pest of the East and, probably because it is 

 striped somewhat like the latter, it is more often called "old- 

 fashioned potato bug" than other species. It can be easily 

 identified by means of the illustration (fig. 36). Although much 

 attached to the potato, this species also does injury to beets, 

 beans, peas, tomatoes, radishes, and melons. 



The Three-lined Blister Beetle (Epicauta lemniscafa Fab.). — 

 This blister beetle very closely resembles the preceding; in fact, 



