AN ACCOUNT OF AN EXPERIMENT TO DETER- 

 MINE THE HEREDITY OF EARLY AND LATE 

 RIPENING IN AN OAT CROSS. 



By A. St CLAIR CAPORN. 



(With one text-figure.) 



Systematic experiments on the maturation of cereal crops have 

 not commended themselves to Mendelian workers, partly because the 

 matter involved the study of characters obviously influenced to a 

 certain extent by climatic and edaphic conditions, and partly because 

 the amount of labour necessary seemed hardly commensurate with the 

 results apparently to be expected. Observations therefore have been 

 of a rough and ready kind, generally incidental notes made during the 

 course of experiments with some other principal object in view. It 

 was known, for instance, that when a spring wheat like T. polonicum 

 was crossed with a winter Rivett, the F^ generation was more or less 

 an intermediate in regard to time of ripening. It was also known that 

 in the F^ generation a very extensive scatter took place, though the 

 bulk of the crop tended to be earlier than the late parent. But there 

 was always uncertainty as to precisely how much stress to lay on the 

 fact that one parent was a winter wheat and the other a spring, and it 

 was largely on this account that no fixed standard of ripeness was 

 determined on, and complete statistical analyses made. While the 

 results of the investigation described in this paper cannot be said to 

 be other than puzzling and empirical, they can at any rate claim to 

 present in tabular form the exact maturation values of a whole F^ 

 generation as established by the F^ progeny. 



The two parents chosen were Mesdag and Hopetown. Their ripening 



times in 1913 were 



Mesdag. July 26th. 



Hopetown, August 13th. 



17—2 



