122 Atavism. 



acter. For if the seeds of striped individuals which have 

 been artificially self-fertilized are harvested and sown, 

 we usually obtain some plants with uniformly red flowers. 



The striped varieties therefore give rise to red plants 

 from time to time, and in my cultures, which extend over 

 about eight years, A. in. ! lit cum rnbro-striatum has done 

 so almost every year in spite of being self-fertilized. 

 As the original wild form is uniformly colored (that is, 

 not striped, for the color itself is composed of white, 

 red and yellow) the loss of the striping may be regarded 

 as a case of atavism. 



jMoreover this phenomenon of atavism was exhibited 

 by my cultures in two other forms (Plate I) : on the one 

 hand as a bud-variation in which whole branches of a 

 plant with striped flowers revert to the red type ; on the 

 other hand as a lateral or sectorial variation, to adopt 

 Heinsius's term,^ in which one side of the spike bears 

 uniform flowers, whilst the other bears striped ones. 

 Let us examine these two cases more closely. 



In the case of bud-variation a striped plant bears a 

 branch all of whose flowers are red, without striping. 

 If, as is usually the case, the plant flowers on 6-8 or 

 more lateral branches the abnormality is very striking. 

 A single plant very seldom bears two branches with red 

 flowers, and it scarcely ever happens, if indeed it ever 

 does, that the terminal portion of the main stem has red, 

 and the branches striped flowers. As a rule it is one of 

 the lower stronger branches which is atavistic and seldom 

 one of the higher weaker ones. I occasionally found a 

 tertiary branch Avith red flowers, i. e., a lateral twig nf 

 a striped branch. As might be expected, the coarsely 



' H. \V. Heinsii's. 07'cr hontc hhidcrcn, Genootschap v. Natinir-, 

 Genees- en Heelkunde, Biologische Scctic, May. y, 1898. p. 2. 



