THE NATURE OF BUD VARIATIONS AS 

 INDICATED BY THEIR MODE 

 OF INHERITANCE^ 



The title limits this account to such bud variations as 

 have been studied critically with respect to their inheri- 

 tance in sexual reproduction. The further limitation of 

 time makes it necessary that I choose from among such 

 studies certain cases to serve as illustrations of the sev- 

 eral types of bud variation. I shall, therefore, attempt 

 no complete review of the researches bearing on the prob- 

 lem at hand. 



A survey of published accounts of bud-variation studies 

 shows that as yet comparatively little is definitely known 

 of the real nature of these vegetative sports. It seems 

 not unlikely, however, that to point out some of the prob- 

 lems suggested by these studies and, where possible, to 

 note modes of attack may serve the purpose of this sym- 

 posium quite as well as a rehearsal of known facts and 

 their interpretation. 



As here used, the term bud variation is synonymous 

 with vegetative ias contrasted with seminal variation. 

 The term somatic variation may also Ix' cmijloycd to the 

 same effect, provided it is not thereby intnidiMl to exclude 

 cases in which the germ tract as well ;)> the soma is in- 

 volved. At the outset, however, there must be imposed 

 on any of these terms, for the purpose of this discussion 

 at least, the limitation that the variation involves a 

 change in the genetic constitution of the parts affected. 



The expressions somatic mutation and somatic segre- 

 gation are specific terms and as such are not to be used 

 interchangeably with the more general terms somatic, 

 vegetative, or bud variations. Moreover, to speak of a 

 particular vegetative variation as a case of somatic muta- 



1 Paper No. 94, Department of Plant Breeding, Cornell University, Ithaca, 

 64 



