22 Pi-arl and Bartlett. 



except in presence of ss, which we assume to inhibit the expression 

 of AA, when according to the same hypotliesis used in the previous 

 cases 



^^^ 1.59 + 2.09 ^ 



2 



and Aa = 2.09. 

 Then for the starchy Fg kernels we have, without repeating the 

 details of the computations, which are in principle identical with 

 those of the previous cases: 



1.64 = expected percentage of ash in Fo starchy kernels. 

 1.495 = observed mean percentage of ash in all Fg starchy 

 kernels (yellow obs. = 1.49, white obs. = 1.50). 

 Difference between observation and theory = 0.145. 

 For the sweet Fo kernels we have 



2.03 =^ expected percentage of ash in Fo sweet kernels. 

 1.90 = observed mean percentage of ash in all F2 sweet 



kernels (yellow obs. = 1.96, white obs. = 1.84). 

 Difference between observation and theory = 0.13. 

 Here again the differences are small, both absolutely and relatively, 

 and the results indicate that ash content is inherited as an 

 independent unit character. 



In the cases so far considered the results have been such as to 

 indicate strongly the independent segregation of each character. 



We come now to a group of characters where the correspondence 

 between observation and theory is somewhat less close, though even 

 here the indication of separate segregation of the characters is clear. 

 The group includes "crude fiber" and "pentosans". It will be noted 

 that we are here dealing with carbohydrates. This, as we shall see 

 gives the clue to the probable reason for the lack of closer agreement 

 in the figures. 



For crude fiber, we get, by the same method of procedure as in 

 the other cases, the following results: 



2.145 = expected percentage of crude fiber in Fo starchy 



kernels. 

 1.875 = observed mean percentage of crude fiber in all Fo 



starchy kernels. 

 Difference between observation and theory for starchy kernels 

 = .270. This is relatively a larger error than any so far observed. 

 For the sweet kernels the results are: 



