﻿STUDIES OF THE PINK BOLLWOEM IN MEXICO 5 



boll itself. The great excess of the number of eggs on the bolls above 

 the number of larvae in the bolls shows that the failure of many young 

 larvffi to enter the bolls must be assigned to causes other than distance 

 from the bolls at time of hatching. 



The favorite position of the eggs on the bolls is between the wall 

 of the boll and the calyx. A cluster of eggs in this characteristic 

 position is shown on the calyx of the boll in Figure 3. 



ENTRANCE OF THE YOUNG LARVA INTO THE BOLL 



The entrance hole made by the young larva into the boll is very 

 small but quite distinguishable. Numbers of these punctures are 

 sho-^\Ti on the boll in Figure 3. The young larva seems to show no 



Fio. 3.— Work of pink bollworm on cotton boll. At left: Cotton boll showing entrance holes of 

 young pink bollworm larvae and cluster of eggs on calyx. At right: Carpel showing characteristic 

 tunneling by young larvae under inner surface of wall before entering lock 



particular preference as to where it attempts to enter the boll. Some 

 counts were made on October 11 and 14, 1921, to determine whether 

 any appreciable number of larvae enter the boll at points covered by 

 the calyx. The results are shown in Table 2. 



Table 2. — Punctures by the pink hollworm under the calyx and at other points on 



the boll 



Num- 

 ber of 

 bolls 



89 



Nu 



Under 

 calyx 



rnbcr of en 



Above 

 calyx 



trance bol 

 Total 

 r.,791 



3S— 



Per boll 



Percent- 

 age 

 under 

 calyx 



113 



8,678 



68 



1.08 



