skin at the bottom where the burrow is somewhat enlarged, and there 

 enters the pupal or resting stage. The accompanying figure (fig. 2) 

 illustrates the general form of a cell, with the pupa in its normal 

 position. 



As is the case with the egg and larval stages, the pupal stage is 

 shortest during the summer months, usually lasting from twelve to 

 sixteen days. The insect passes the winter as a pupa. 



Fig. 2. — Vei't'ca' section through the soil, showing pupa of bollworm in its burrow. 

 (Copied from Quaintance and Brues.) 



The fact that the adult is unable to make its escape when the pupa 

 is buried under a few inches of dirt and that the pupa itself is killed 

 by undue exposure immediately suggests the importance of fall 

 and winter plowing so as to destroy these cells and thus expose the 

 pupse to the inclemencies of the winter weather and to destruction 

 by birds and other enemies. This phase of the subject will be dis- 

 cussed later within these j)ages. 



29483— No. 290—07 m 2 



