j2 Pearl and Bartlett. 



degree of maturity and equal period and condition of drying there 

 is a marked difference between the sweet and starchy kernels in respect 

 to retained moisture. Thus, in F, we see clear evidence of segregation 

 in respect to this character, the differences between the Fo kernels 

 being exactly those which we have seen to be typical when pure 

 starchy and pure sweet varieties of maize are compared. These diffe- 

 rences in retained moisture after equal extent of drying undoubtedly 

 depend upon physical or structural differences in the kernel, and 

 probably primarily on starch content. 



Nitrogen and Protein. Since the figures tabled as protein are, in 

 accord with the usual custom, derived from the nitrogen determinations 

 simply by multiplying by the factor 6.25 we may consider these 

 together. It is quite apparent that in Fg there is a segregation with 

 respect to protein content of the kernels. Averaging in Fg both 

 starchy classes together and both sweet classes together we find that 

 the latter run approximately one percent higher in protein content 

 than the former. Actually in the case of the direct determinations 

 (Table I), the sweet kernels are 1.18 percent higher in protein content 

 than the starchy, while the figures in Table II on a water free basis 

 show an excess of 0.99 percent of the sweet over the starchy in 

 respect to protein content. 



While there can thus be no doubt as to the reality of the segre- 

 gation in F2 in respect to this character it is of interest to note that 

 there is an increase in the protein content of the Fo starchy kernels 

 of both yellow and white classes as compared with the original dent 

 parent or with the F^ kernels. That is, the "low protein" segregate 

 has a higher protein content than the pure "low protein", parent or 

 the Fl kernels in which "low protein" is the dominant condition. 

 In the case of the sweet kernels (either yellow or white) in Fg there 

 is only a very slight and probably quite insignificant increase of 

 protein content as compared with the original white sweet parent. 

 The meaning of these facts wiU appear in a later section. 



A matter of much interest in connection with the matters here 

 under discussion (nitrogen and protein content) lies in the fact this 

 character is in no way directly related to the group of physical 

 and chemical attributes which give starchy and sweet kernels their 

 distinctive characters as such. It is obvious that certain chemical 

 characters must segregate as a part of the complex which gives rise 

 to the external, physical appearance of the kernels. The most obvious 



