No. 603] SHOETER ARTICLES AND DISCUSSION 



191 



whereas the mean deviation of offspring from parent in cases in 

 which the earlier parent gives the later progeny is larger, 0.65 

 day. The only conclusion from Hoshino's Table 6 is the one he 

 makes himself, namely, that the variation is insignificant. 



"We are sure that no unbiased person would conclude from the 

 negative facts in the table in question that the variation in 

 these pure lines was genotypic, or that selection in these groups 

 has had an appreciable effect. 



On page 332 Dr. Castle writes : 



If I have correctly interpreted Hoshino's observations, flowering time 

 in peas is clearly a Mendelian unit character, entirely devoid of domi- 



end product of a single cross between early and late varieties. 



Indeed, if Hoshino's work on the inheritance of flowering-time 

 of peas were the only, or the first, or the most comprehensive of 

 its kind, we could see reasons for such a belief. But Hoshino 

 only crossed two varieties differing in time of flowering. But 

 in peas there do not exist only one late and one early variety, but 

 several thousands, each with its own time of flowering. It 

 would not be difficult to give a list of ten names of pea-varieties 

 of which in every preceding one all the plants would be in flower 

 before one of the next opened its first flower. Therefore crossing 

 experiments involving two varieties can never be sufficient basis 

 from which to conclude that flowering-time in peas is one thing 

 or the other. 



Tschernack, in his well-known experiments with flowering-time 

 of peas (1911, Mendel's Festchrift), cited by Hoshino, made 

 eight different variety-crosses. Whereas in Hoshino's work the 

 two varieties crossed happened to be of such a constitution, that 

 in the resulting generation there did not occur plants which 

 commenced flowering at an earlier time than the earliest parent, 

 or at a later date than the latest parent, in Tschernack 's work 

 such cases were met with. In Tschernack 's experiment No. 81 

 (1906) there were in found plants flowering seven days 

 earlier than the early parent; in experiment No. 82 (1916) even 

 plants beginning flowering nine days earlier than the early 

 parent. In experiment No. 81 (1906) there were also found 

 plants starting to flower four days after the latest parent, and 

 in experiment 38 (1902) there were plants, which did not begin 

 to flower before the late parent had been in flower for a week. 



It is perfectly clear, that a sort of blending may be the result 

 of a difference between the parents in a number of genes, in- 

 fluencing the quality under observation in different directions. 



