196 



INSECTS INJURIOUS TO STAPLE CROPS. 



each plant. Some fourteen different kinds of grasshojipers 

 have been known to injure cotton, but of these the Ameri- 

 can Acridium [ScUistocerca ame7'icana) and the Differential 

 Locust (see page 69) are the most injurious. 



Fig. 109. — Granulated Cnt-worm {Agroiis annexa). n, larva; /, 

 pupa; 7i, adult— natural size. (After Howard, U. S Dept. Agr.) 



Fig. 110. — The American Acridium {ScMstocerca americana Scud.). 



(After Riley.) 



Caterpillars. 



Many species of Lepidopterous larvae occasionally defoli- 

 ate the cotton-plant, among the most common being the 

 Bag-worm {Tliyridopterijx e2)hemercBformis), Fall Army- 

 worm (Laphygma friigiperda) (see page 84), Garden Web- 

 worm {Loxostege similalis) (see page 260), and the Leaf- 

 roller [Caccecia rosaceana). Any of these may be destroyed 



