No. 560] GENETIC AL STUDIES ON OENOTHERA 467 



rosette 12.59^ (compare Fig. 9 with Fig. 7) of the F 3 

 from one of the dwarfs in the F 2 , 11.42ra (similar to Fig. 

 5). Figs. 7 and 9 then illustrate the same behavior, in 

 the first case that of the F 2 plant 11.42/, and in the second 

 case that of the F 2 sister plant H.42#, and both plants 

 have produced a class of dwarfs similar to that which 

 appeared in the F 2 11.42r, the type shown in Fig. 5. I 

 had the same difficulty with the 20 dwarfs from 11.42# as 

 with the 8 from 11.42/ and was only able to save 7 plants 

 from a period of drought. These at the present writing 

 are also in the hothouse, where they bid fair to reach 

 maturity. 3 



An outline of the genealogy of the sets of dwarfs pro- 

 duced by the family from the F a hybrid 10.30L& will make 

 clearer its complications. The important feature is of 

 course the close parallelism of this history with the be- 

 havior of Lamarckiana when it produces in successive 

 generations a marked variant that breeds true. 



11.42/ (Fig. 6). 11.42* 



