478 TEOCEEDINGS OF THE THIRD EN^TOMOLOGICAL MEETING 



in 1916, 1917 and 1918, only two or three pupse have been found. Traces 

 of previous occupation were very frequent, as the larvse when full grown 

 desert the boll to pupate elsewhere. We have observed and recorded 

 in 1917 and 1918 about 50,000 such traces of previous occupation (1917 — 

 35,495 ; 1918,-14,301). We cannot therefore give unqualified assent 

 to Busck's statements.—" The larva normally makes its cocoon and 

 pupates within the boll, partly within the last seed attacked " {Journal 

 Agriculture Research, IX, No. 10, p. 353, line 5) and " under normal 

 conditions in the field, however, the pupation nearly always takes place 

 within the boll " {ihid.. line 19). Larvse arrived in a seed-store with 

 seed almost invariably leave the seed and pupate in the angle between 

 the line of contact of two sacks or in crevices of the masonry of the 

 walls, or between the floor-boards. The pupal period has been observed 

 to vary from 10 days to 2 weeks. Busck gives it as 10 — 20 days. 

 Control of the insect at this stage is not feasible as pupae are not easily 

 found in seed stores, even when abundant, and are practically unfind- 

 able outside. Before pupating, the caterpillar spins a cocoon, and 

 requires a few days for its transformation. 



The pupa is enclosed in a silken cocoon, and is found sometimes 

 in the lint of an open boll, on the soil, under refuse in the fields between 

 the bract and the boll, or between dead leaves. Willcocks remarks 

 on their frequence in fallen flowers on the ground, and in fallen bolls. 

 Short-cycle larvae spin only one cocoon, that in which the pupa- 

 tion takes place, whilst long-cycle larvae spin up inside hollow seeds 

 for their resting period and leave their resting place to spin their pupal 

 cocoon, which is more elongate and loosely woven than the resting shelter. 

 Whilst resting they are doubled up, head to tail. 



The moth is crepuscular or nocturnal in its habits. During the 

 day it is very diflB.cult to find in fields, or in seed-stores, where one knows 

 it to be present ; if disturbed, it escapes by running swiftly and hiding 

 under any shelter it can find. 



" During the day-time the moth very rarely takes to wing, but at 

 night it can fly long distances when circumstances are favourable. At 

 night it is readily attracted to artificial light. Unfortunately light- 

 traps do not form a rehable method of control. No method of control 

 during the adult stage seems possible. 



Emergence of moths from the long-cycle brood appears to depend 

 very considerably upon the conditions under which they wintered. 

 Thus it is now no longer possible to make any absolute statement of 

 the period at which the maximum of emergence may be expected. It 

 has been found that the larvae Uving in bolls lying on the ground, which 

 consequently are kept slightly moist, are earher to emerge, and give 



