90 



MISSOURI AGRICULTURAL REPORT. 



shelled corn per acre it requires that the ears shall have good sized cobs. 

 Possibly the corn which shall ultimately surpass all others for yield per 

 acre will have tapering and not cylindrical ears. These are some of the 

 points regarding which men have some ideas and opinions, but as yet 

 v/e have no definite facts, and we shall need several years more to 

 obtain absolute knowledge regarding some of these points. Let us base 

 our selections of seed corn first upon known facts and performance rec- 

 ords, and secondly upon what one may call his "type" of corn. 



CHEMICAL SELECTION BY MECHANICAL EXAMINATION. 



The selection of seed ears for improved chemical composition by 

 mechanical examination of the kernels is not only of much assistance to 

 the chemist in enabling him to reduce greatly the chemical work involved 

 in seed corn selection, but it is of the greatest practical value to the 

 ordinary seed corn grower who is trying to improve his seed corn with 

 very limited service, if any, from the analytical chemist. This chemica' 

 selection of seed ears by mechanical examination, as well as by chemical 

 analysis (which is described below), is based upon two facts: 



1. That the ear of corn is approximately uniform throughout in 

 the chemical composition of its kernels. 



2. That there is a wide variation in the chemical composition of 

 dififerent ears, even of the same variety of corn. These two facts are 

 well illustrated in Table i. 



TABLE l-PUOTEIN IN SINGLE KERNELS. 



Ear A, 



protein, 

 per cent. 





EarB, 



protein, 

 per cent. 



EarC, 

 protein. 



EarD, 

 protein, 



per cent, per cent. 



Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 

 Kernel 



No. 

 No. 

 No. 

 No. 

 No. 

 No. 

 No. 

 No. 

 No. 

 No. 



3.. 



4.. 

 5 . 



(!.. 

 7. 



8 . 



9 . 

 10. 



12.46 

 12.54 

 12.44 

 12.50 

 12.30 

 12.49 

 12.50 

 12.14 

 12.14 

 12.71 



11.53 

 12.32 

 12.19 j 

 12.54 I 

 12.14 I 



12.95 



12.84 



» 



12.04 

 12.75 



♦Determination lost by accident. 



It will be observed that, while there are, of course, small differ- 

 ences among the diflferent kernels of the same ear, yet each ear has an 

 individuality as a whole, the diflfcrcnce in composition between different 

 ears being much more marked than between different kernels of the 

 same ear. 



The uniformity of the individual ear makes it possible to estimate 

 or ti'O determine the composition of the corn by the examination or anal- 

 ysis of a few kernels. The remainder of the kernels on the ear may 



