THEORIES OF DEVELOPMENT 



whose petals showed a trace of cloudiness, are 

 other striking examples of the accentuation of a 

 character through line breeding. 



The sturdy winter rhubarb has been developed 

 in the same way from the plant imported from 

 New Zealand with a stem no larger than a pencil. 

 The absolutely smooth cactus is the descendant 

 of plants that only showed a tendency to be some- 

 what less spiny than their fellows. 



CREATION OR RECRUDESCENCE 



An interesting question arises as to whether 

 such accentuation of a peculiarity or tendency 

 may amount to the bringing out of a new char- 

 acter that was not represented in any ancestor, 

 near or remote. 



Is Mr. Burbank's light blue poppy, for example, 

 the first of its kind; or were there blue flowers 

 among some of the ancestors of the poppy? 



The best view appears to be that the seemingly 

 new trait was really submerged in the ancestral 

 germ-plasm, if the phrase be allowed, and has 

 been made tangible by the removal of more or 

 less antagonistic traits that obscured it. In the 

 case of the blue poppy, for example, the sub- 

 mergence was doubtless of long duration, for blue 

 poppies have not been in fashion within the mem- 

 ory of man; but through successive generations 

 of selection the factors for redness and yellow- 

 ness were removed, and an individual finally pro- 

 duced in which the primal blue, which was prob- 



[35] 



