No. 532] GENETIC AL STUDIES ON (ENOTHEBA 219 



cultures which of the two, the resemblances or the dif- 

 ferences, are more stable in inheritance and variation. 



The type of Lamarckiana which has been compared in 

 this paper with the hybrids of biennis and (jraudillora 

 is one with which I have been familiar for the past five 

 years. It has been represented in my cultures by strains 

 from seed that has come to me through three different 

 sources, all of the seed, however, originally being de- 

 rived from the cultures of De Vries. These strains have 

 not differed materially from one another, and as grown 

 in my small cultures have not exhibited marked varia- 

 tion. The rosettes and mature plants have agreed in 

 habit and foliage with the descriptions of Lamarckiana 

 in ''Die Mutationstheorie." The flowers have, however, 

 been uniformly smaller than the measurements and fig- 

 ures of De Vries, the petals being about 2.5 cm. long in- 

 stead of measuring 3 cm. or more. In the flower strur 

 ture the position of the stigma has proved more variable 

 than one would be led to suppose by the figures and de- 

 scriptions of Lamarckiana, the stigma generally being 

 but slightly above the tips of the anthers or about at 

 their level, and in some plants distinctly below. 



2. grandiflora B X biennis B (10.18), and the recipro- 

 cal cross (10.19). From about 200 seedlings of the 

 first culture and about 250 seedlings of the second cul- 

 ture, 66 and 70 plants, respectively, were brought to 

 maturity, being selected for the breadth of the cotyle- 

 don and the shortness of its petiole. As the rosettes 

 formed there appeared much variation in the amount 

 of anthocyan developed in the leaves, the larger propor- 

 tion being marked with dull red spots and blotches, only 

 a small number having few spots as in Lamarckiana. 

 The form of the leaves likewise varied and certain of the 

 rosettes were readily separated as being more biennis- 

 Hke or yrandi flora-like than the average. The plants 

 that developed from these extreme forms of rosettes were 

 also somewhat more like the respective parents than the 

 mass of the culture which presented the characters of 



