230 



MASS MUTATIONS AND TWIN HYBRIDS OF 



ovata at the beginning of the flowering period, I found the figures 

 as given in table VIII. 



The percentage figure for type-/? conforms to the formula of 

 Mendel for monohybrids, assuming the initial rosettes to be domi- 

 nant over their absence, but in the cross of 0. grandiflora with 

 biennis the reverse was the case. Possibly the linkage was different 



Table VIII 



Table IX 



Third generation from ovata 



in the two instances: In these second generations I self-fertilized 

 some individuals and cultivated their offspring in 1916. Table 

 IX gives their offspring. This gives a percentage of 42 for the 

 splitting off of type R from the others, and this figure seems to 



