51 



and at night, lays its eggs scattered over the food plant. The 

 larvae vary much in colour and markings. The more common 

 form is of a greyish green colour on the sides, with two 

 darker stripes along the back, separated by a narrow light 

 stripe. The pupa is formed in the ground, 2 or 3 inches 

 below the surface, in a small earthen cell within which the 

 caterpillar encloses itself after feeding and growth have 

 been completed. The life-cycle occupies about six weeks 

 The caterpillar tunnels into the cotton bolls (Fig. 49), com- 

 pletely destroying the interior, and indeed often entirely 

 consuming the contents of them. 



The corn ear worn (Laphygma frugiperda, S. and A.) 

 Fig. 50 also occurs as a boll worm of cotton in the West 



Indies. Neither of these 

 insects is known as a 

 serious pest of cotton in 

 these islands, although 

 both are known to occur, 

 and both are pests of 

 Indian corn. 



Control. The des- 

 truction of infested bolls 

 containing the larvae wil 

 result in reducing con 

 siderably the numbers of 

 these insects. Measures 

 for control when they 

 attack Indian corn should 

 also be useful for reducing 

 their numbers as cotton 

 Fig. so. Corn ear worm. pests. The use of Paris 



(a) moth ; (b) forcing; (c) larva ; green or other arsenical 

 (d) abdominal segment of larva, lateral poison Oil the cotton 

 view ;(e) pupa, lateral view, (d) twice p l an ts assists in the con- 

 naturalsize.a 6, c e one fourth natur- r f u aco ^acfc ; 11PP 



al size. {From U.S. Dept. Agric.) trol oi these pests, since 



the larvae feed on the 

 leaves for a short time and have to eat their way into the 

 bolls, and they may be poisoned in so doing. 



Trap Crops. It is sometimes possible, when the insects 

 become numerous, to plant corn and cowpeas near cotton 

 fields, at a time that they will be attractive to the egg- 

 laving moths, before the cotton bolls are formed j so that the 



