302 Miss M. Wheldale. The Inheritance of [Feb. 12, 



Professor De Vries' parent plants would be (El = rose lips, Et = rose 

 tube) : — 



YY II El El LL Et Et Magenta (El Et L = magenta) 



YY II rl rl 11 rt rt Ivory 



and the cross-breds : — 



YY II El rl LI Et rt Magenta 



would give, on selling : — - 







Ratios. 



Numbers 

 calculated. 



Numbers 

 observed. 



El LRt ... 



RIL 



RlRt 



LRt 



Rl 



Magenta 



per cent. 

 36 or 56 

 12 19 

 9 14 



3 1 

 -47 11 



4j 



per cent. 

 56 

 24 

 15 



5 



„ delila 





Rose delila 



L 



Magenta delila 



Rt 















The ivories and rose delilas are classed together as De Vries' whites and 

 tinged whites. The numbers observed are the mean of those given for the 

 three experiments ; moreover, the various kinds of roth and fleischfarhig would 

 be found among the above F 2 forms. 



In conclusion, I wish most sincerely to thank Miss Saunders and Mr. Bateson 

 for the advice and help they have kindly given me, both as regards many 

 practical details and in the writing of this paper. 



I am also indebted to Mr. Lynch, of the Botanic Gardens, Cambridge, for 

 allowing me space under cover every year for the germination of my 

 seedlings. 



