No. 560] GENETIC AL STUDIES ON OENOTHERA 



461 



will be found in my last contribution (Davis, '12a, pp. 

 413-415). From the F 2 generation of 992 rosettes, cul- 

 ture 11.42, a group of 147 were sharply distinguished by 

 their uniformly small size and narrow leaves. These de- 

 veloped into a class of 

 very remarkable dwarf 

 plants (Davis, '12a, p. 415, 

 11.42r) which at maturity 

 were from 3-4 dm. high, 

 rarely branched, and bore 

 medium-sized flowers 

 (Fig. 5). The leaves of 

 the rosettes and mature 

 plants were fully green; 

 there was no etiolation so 

 characteristic of the group 

 of dwarfs from the sister 

 F, hybrid 10.30La. The 

 character of the young 

 dwarf rosettes is shown in 

 Fig. 7 and Fig. 9, 12.59a, 

 in comparison with ro- 

 settes (shown above) sim- 

 ilar to forms representa- 

 tive of the mass of the 

 culture. 



The rosettes constitu- 

 ting the mass of the cul- 

 ture exhibited a wide 

 range of form with the ex- 

 tremes approaching the 

 rosettes of the biennis and 

 grandiflora parents; there 



Was not Shown a Clearly }7raBx biennis A. This plant came from 



defined tendency towards "Jo™^" 6 simllar t0 that 8nown in Fig " 

 either parent of the cross. 



From these rosettes a much more varied culture devel- 

 oped than the F 2 generation from the plant 10.30La. 



