STUDIES OF THE PINK BOLLWORM 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 
larvae 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 
shown on the boll in Figure 3. The young larva seems to show no 
Fig. 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 bollworm under the calyx and at other points on 
the boll 
Num- 
ber of 
bolls 
Number of entrance holes— 
Percent- 
age 1 
under 
calyx 
Under Above 
calyx 1 calyx 
Total 
Per boll 
89 
113 
5,678 
5,791 
65 I 1. 95 
