The Bulletin. 



37 



It passes this stage in an oval cell in the earth. It is of a brown color 

 and entirely helpless, as this is merely a transformation stage, when 

 the larva is being formed into the adult moth. This stage of the 

 insect lasts from one to four weeks (or over winter), at the end of 

 which time the adult insect emerges. The adult insects mate and 

 deposit eggs for another brood, and then die. 



There are several distinct generations of the insect each year, 

 the exact number having never yet been definitely determined for 

 North Carolina, but it seems likely that in eastern North Carolina 

 there are at least five distinct broods and in the piedmont section 

 four or five broods. The winter is passed in the pupa stage in the 

 ground. 



It is interesting to know that the larvse are cannibals and not 

 infrequently eat one another. This is (to us) a very beneficial habit 

 and worthy of all possible encouragement, but as it takes place duly 

 when they are numerous enough to come into competition for pos- 

 session of food, there will always be enough left to do serious damage. 



Fig. 15. — Boll cut open to show Boll-worm at work inside. Natural size. 

 (After Quaintance, Bur. Ent., U. S. Dept. Agr.) 



. Com seems to be the preferred food of the Boll-worm, for the 

 adult moths lay their eggs on fresh com silk in preference to any- 

 thing else. But when the kernels have become hardened they turn to 

 cotton and other crops. 



Professor Quaintance states* that noticeable injury to cotton 

 begins with the August generation of caterpillars. When a young 

 square is attacked it "flares" and drops from the plant. This injury 



*Farmers' Bulletin 191, U. S. Dept. Agr., "The Cotton Boll-worm." 



