The Mendelian Inheritance of Certain Cliemical Characters in Maize. i^ 



of these characters, of course, is the starch content. The external 

 physic;ü quaUties by which one can tell at once whether a grain 

 belongs in the starchy (dent) class or, on the other hand, in the sweet 

 class are in no way directly related to the protein or nitrogen content 

 of the kernels. We may have perfectly characteristic sweet kernels 

 of either high or low nitrogen content and, on the other hand, we 

 may have perfectly good starchy kernels (dent or flint) with either 

 high or low nitrogen content. The analyses given in the present 

 paper, from the nature of the case, do not show this fact, but a 

 study of chemical analyses of maize in general makes it perfectly 

 clear. Thus for example, Straughn (6) in his table III (loc. cit. 

 pp. 48 and 49) gives analyses of different samples of Stowell's Ever- 

 green sweet corn ranging all the way in protein content from as low 

 as 5.35 per cent through a continous series showing such grades as 

 6.32, 7.46, 8.07, 8.34, etc. on up to as high percentages as 11.58, 

 II. 41 and the like. On the other hand, extensive analyses of starchy 

 varieties of corn such as those given by Hopkins (9) for dent maize 

 show variations in protein content all the way from about 8 per cent 

 up to as high as 14.92 per cent. Dent corns of higher content than 

 this last figure have been analyzed. 



We have in the present results, then, clear evidence of the 

 Mendelian segregation of an entirely invisible chemical character not 

 directly connected in any way with the general complex of chemical 

 and physical characters which give the kernel its characteristic external 

 appearance. 



Crude Fat. The facts here are essentially similar to those already 

 brought out for nitrogen and protein content, with some minor diffe- 

 rences. The evidence for the segregation of this character in F, is 

 perfectly clear. The two starchy classes of Fo kernels have a crude 

 fat content only a little more than half as great as that of the two 

 sweet classes of kernels in the same generation. We note here again 

 that the crude fat content of the starchy kernels in F» is considerably 

 higher than the crude fat content of the original yellow dent parent. 

 The significance of this fact will appear later. 



It is of some interest to note that there is a difference in fat 

 content between the yellow and white classes of both sweet and 

 starchy corn in Fg. The white chisses (whether sweet or starchy) 

 run a little higher in crude fat content than do the yellow classes. 

 This might be expected as a probable result if, as actually appears 



