CAUSES AND CONDITIONS OF BUD PROLIFERATION. 49 



frequent than that of the staminal tube, is probably also less effect- 

 ive, since the weevil larvae could escape before it into the center of 

 the flower while the proliferation from the staminal tube grows 

 outward, as though to meet the intruder and keep him separated 

 from the more special organs. 



The habit of the larvae to seek the center of the bud and gnaw 

 off the style is responsible for the loss of large numbers of younger 

 bolls which have suffered no direct injury from the weevil. Even 

 though the larva be subsequently killed by proliferation or though 

 the flower drops off and carries the larva with it. the lack of polli- 

 nation must prevent the development of the young boll unless par- 

 thenogenesis takes place, which seems improbable. 



Larvae were found in several instances in nearly full-sized buds 

 about to open, and in another case a more than half-grown larva 

 was found inside the central column of an open flower. More or less 

 distorted flowers with unmistakable signs of previous proliferation 

 in the bud stages are commonly found in the Kekchi cotton fields. 



Summarizing the results of the study of proliferation in the 

 Kekchi cotton, it may be said that although the frequency of pro- 

 liferation in the young squares is very great, its efficiency in prevent- 

 ing the breeding of the weevils is somewhat less than might be ex- 

 pected in Texas, owing to the difference of food habits among the 

 weevils. If the Texas weevils are as consistent in their habits as 

 now supposed, the introduction of the Kekchi cotton or of a similar 

 proliferating variety might be of great benefit as a preventive 

 measure. The extent, however, to which it could be made to compass 

 the complete destruction of the weevil would depend somewhat upon 

 the degree, if any. to which they might return to the habit shown in 

 Guatemala of feeding upon the ovaries or boll rudiments rather 

 than upon the pollen of the young buds, an important and hitherto 

 unsuspected difference in habits between the weevils of Texas and 

 those of Guatemala. 



CAUSES AND CONDITIONS OF BUD PROLIFERATION. 



That the proliferation is occasioned by the injuries of the weevil is 

 too obvious to admit of doubt, but it may be of much practical 

 importance to learn the exact way in which the new growth of tissue 

 is brought about. The disturbing factor might be either mechanical 

 or chemical. The new growth may be a direct response to injury of 

 the weevils in feeding or laying eggs, or it might be stimulated indi- 

 rectly by the secretions of the young larva, or by chemical changes 

 or decay of the damaged tissue. A second mechanical possibility is 

 that of pressure developed in the young and rapidly growing bud. 

 9902— No. 88—05 u 1 



