90 



PESTS OF THE COTTON PLANT. 





than one-fiftieth of an inch across, round, of a bluish colour, finely ribbed 

 and marked. Within a few days it hatches to a tiny dark coloured 

 caterpillar, which feeds first on the bracts and flowers or eats straig-ht 

 into the rind of the boll. In the former case it attacks the bolls within a 



few days. When no 

 bolls are formed, it tun- 

 nels doAvn the shoots, 

 commencing" at the tip 

 and eating" for a consi- 

 derable distance down 

 the shoot, thus des- 

 Fio. 99. troying it ; normally 



Spoiled BoU-worm. {3Iagmfiedfoin- times.) it cuts its way through 



the rind of the boll and the dcA^eloping" lint, until it reaches a seed, 

 which it eats. Having" destroyed one seed it eats another. If the bolls 

 are small, they frequently drop off, but if a larg-e part of the seeds 

 are eaten, the lint is destroyed and the boll filled with excrement. 

 A single caterpillar will rarely destroy more than one large boll 

 but becomes full-fed in the first. More than one is rarely found in 

 a boll unless small ones enter a boll already tenanted by a large one. 



When the caterpillar is full fed, it 

 leaves the boll and prepares a cocoon of 

 tough grey silk Avithin which it transforms 

 to the pupa. In the black cotton soil of 

 Western India, this is found in the cracks 

 and crevices of the soil. In Cawnpore, 

 Mr. J. M. Hayman states that it is found 

 "on the bolls or bracts, generally between 

 the two,^' and this is the case also iu 

 Beliar and the Punjab. 



The period of pupation is from 8 to 10 

 days but may be longer in the cold wea- 

 ther. Eventually the moths come out, 

 I)air and lay eggs, each moth laying 

 about sixty eggs. The shortest total life 

 history occupies about one month. Moths 

 are to be found flying in the dusk; 

 during the day they hide in the ground 

 or on the cotton plants. They are not 

 attracted by light. Both species also feed 

 upon hJiindi [Hibisms eaculent'm), des- 



Fia. 100. 



Spotted Boll-toorm. 

 {3Iagnified four times.) 



