26 Pearl and Bartlett. 



remarkable way in indicating that the prevaihng interpretation 

 of the Illinois results either wants entire revision, or at least much 

 more critical scrutiny than has hitherto been given it. The results 

 themselves are, of course, of great value and importance. 



The results of this paper have some bearing on still another 

 matter. It is frequently claimed by sweet corn growers in Maine 

 that unless selection is persisted in, sweet corn will in time revert 

 to the 8-rowed, starchy (flint) Indian corn. One of the writers has 

 made careful inquiries to discover whether there is any basis for this 

 statement and has as yet not been able to find that there is, except 

 insofar as concerns number of rows. It appears from the statement 

 of reliable men that there have been numerous instances in Maine 

 of a very fine grained sweet corn (with 14 to 20 rows to the ear) 

 reverting in the absence of selection for this character to a coarser 

 grained condition i). If sugary endosperm is a definite unit character, 

 as appears to be the case, it is difficult to understand how a sweet 

 corn could revert to a starchy condition, except through some process 

 whereby the sugar character was definitely segregated out. As a 

 matter of fact there appears to be no good evidence that sweet corn 

 will revert to starchy in the absence of selection. The earliest know- 

 ledge of maize which we have includes sweet or sugary kinds distinct 

 from starchy kinds. On this point Sturtevant (14) says: "We have 

 no evidence, I speak after careful research, that any new forms of 

 maize have appeared from our two centuries or more of civilized 

 cultivation. The various agricultural species of maize, the flints, dents, 

 softs, sweets and pops appear to be original forms ; the subdivisions 

 of these into local forms appear to have been about as well accom- 

 plished by the Indians as by ourselves." 



A matter which needs further detailed investigation in continuation 

 of the work here reported is the chemical composition of the different 

 parts of the kernel in cross-bred maize. Hopkins, Smith and East (15) 

 have shown that the different parts of the kernel in dent corn are 

 very different in chemical composition. It would be a matter of 

 much interest to carry out similar studies for sweet corn and for Fj 

 and F2 cross-bred progeny. 



The results of this study of the manner of inheritance of certain in- 

 visible chemical characters in maize may be summarily stated as follows : 



1) In view of the work of East and Shull it is not difficult to understand how 

 this would occur, considering the genotypically mixed condition of the ordinary- 

 strains of corn. 



