64 LUTHER BURBANK 



or proliferation of the new tissue was pro- 

 nounced, as it is in certain individuals, the weevil 

 might be exterminated. It is considered possible 

 that such a variety may exist at the present time 

 in some parts of tropical America, and that if 

 such a resistant variety can be found, it may be 

 possible to develop the characters in the culti- 

 vated plant through selection. 



Inasmuch as individual plants show this power 

 of resistance, there should be no difficulty in de- 

 veloping and raising cotton plants in which this 

 resistant quality is a uniform characteristic. The 

 problem is obviously identical in principle with 

 numberless other problems of plant development 

 that have been solved in the same way. 



And here, also, we may reasonably assume, aid 

 may be secured through the careful cross-pollen- 

 izing of resistant individuals, even if no resistant 

 species can be found with which to effect hybrid- 

 ization. It is reported that a tree cotton indig- 

 enous to southern Mexico is partially resistant 

 to the weevil. 



It will be of interest to determine whether the 

 peculiar characteristic as to growth of new tissue 

 that makes the individual cotton plants resistant 

 to the weevil constitutes a unit character that will 

 be transmitted along Mendelian lines, compa- 

 rable therefore to immunity and susceptibility to 



