PROLIFERATION FROM WALL OF BOLL. 59 



stain. Such a discoloration often spreads back into the loose tissue 

 and then gradually extends over the whole lock of cotton of that 

 particular chamber. The seeds fail to develop and finally shrivel up. 



If the proliferation results, as usual, in the death of the weevil 

 egg or young larva, the process of abnormal growth ceases with 

 the formation of a knob or button of the new tissue on the inside 

 of the wall of the boll. When, however, the young weevil escapes 

 destruction and continues to eat and grow, the proliferating tissue 

 also continues to increase, until in some instances the whole compart- 

 ment is filled with a silvery-white cheesy material which seems to 

 arise not only from about the original perforation of the outer wall, 

 but also from other parts which have been injured and irritated 

 by the presence of the weevil larva. This, with other facts already 

 stated, seems to show that in some varieties of cotton, at least, the 

 tendency to proliferation is very general, or, in other words, con- 

 stitutional, which warrants a larger hope of increasing this character 

 and making it uniform by selection. 



When proliferation, which results from the presence of the weevil 

 larva, has become very extensive and fills the entire compartment, 

 the weevil larva is sometimes found to have eaten through the dis- 

 sepiment into the next chamber, perhaps to escape starvation. Such 

 extensive proliferation, accompanied by the failure of the seeds to 

 develop, means, of course, that the weevils gained entrance while the 

 boll was still very young. Moreover, if the boll had been older 

 there would have been plenty of food for the larva without the 

 necessity of entering a second compartment. Finally, the dissepi- 

 ment would have been too tough for the larva to penetrate easily. 



Further proof of the fact that the weevil larvae are seldom or 

 never able to gain a footing in the larger bolls is to be found in the 

 fact, already stated, that the weevil larvse found in them are nearly 

 always in undersized compartments, much smaller than those which 

 have remained uninjured, and have thus been able to continue their 

 normal development. 



It is to be supposed, perhaps, that if the weevils could gain access 

 to large bolls and feed upon the nearly adult seed they would be able 

 to develop in less time than they usually spend in reaching maturity 

 on the rather poor provender they secure among the abnormal tis- 

 sues which arise after they have entered the young bolls. 



The exclusion of the weevil from the large bolls has been evidently 

 not only an important measure of protection for the cotton, but it 

 has probably comjDelled the weevil to accustom itself to a gradually 

 longer and less prosperous development in the boll. The develop- 

 ment of the weevil-resisting adaptations on the part of the cotton 

 plant has left the insect with two opposite alternatives. It must 

 enter the boll early and submit to a very long period of development 



