230 ON THE INHERITANCE OF THE FLOWERING TIME IN PEAS AND RICE 
niak, the grouping of tlic individuals in the into three classes (early, inter- 
mediate and late), on the numerical ratios of which Tschermak layed great 
stress, seems to be quite arbitrary, and the materials of the and raisings 
are insufficient for the affirmation of the proposed interpretation. In regard 
to the work of Punnet and Baile}', the experimental material seems to us 
too scanty to prove their iissumption positively. 
Thus, so long as the number and nature of the factors are not definitely 
explained, we should have still to hold with Shull (1914), that "for the pre- 
sent, the hypothesis that plural Mendel ian genes adequately account for the 
inheritance of complex quantitative andiphysiological character, is valuable 
only to the extent that it is made a working hypothesis." 
The author has continued the present experiments since 1907. In the 
experiments with peas, he has raised the F^ and the Fg three times and the 
F4 twice, and, besides, he has paid special attention to the inheritance of the 
flowering time of pure lines in the population of parent varieties. The total 
number of individuals which he has raised up to the present is over 30,000. 
As the results of this large raising, the author feels quite confident that the 
present work will cast a clearer light than has hitherto been shed upon the 
multiple-factor hypothesis, which will be applicable to the inheritance of 
such a physiological character as flowering time. 
While the author was conducting experiments on the inheritance of 
flowertng time, he noticed the presence of some correlation between the 
flowering time and flower colour in peas, and found that this correlation 
might be interpreted by the assumption of gametic coupling. 
The author wishes to make grateful acknowledgement for the faithful 
assistance of the following gentlemen; — Messrs. G. Shimada and W. Oga- 
wa, his former assistants, and Mr. Y. Shi ma, his present assistant. 
Sapporo, April, I<)i5. 
