(",20 



THE AMEBIC AN NATURALIST [Vol.XLVI 



dieted 3 that the latter explanation was the true one, and the 

 results from another generation (grown in 1911 from hand 

 pollenated ears) have substantiated the prediction. Our data 

 for this year show that the branched form of ear and its ac- 

 companying tassel type are recessive to the fasciated, cylindri- 

 cal form of ear from which they originated. 



Perhaps no one is ready to draw the limits upon that inde- 

 finable term "species," but Mendelian studies have thrown a 

 bright light upon this mooted question. It is now very evident 

 that sterility in hybrids is not a safe guide for determining 

 what shall be a species. Darwin reported a number of cases to 

 show the fallacy of this theory which was at one time advanced 

 by Kolreuter, Gartner and others. Mendelian studies have 

 disclosed a number of cases of sterility (I have found several 

 in corn) which are not due to hybridization nor to species' dif- 

 ferences. 



Systematic classification should be founded upon either the 

 genotype or upon the Mendelian basis. The genotype basis 

 would be feasible for self-bred and apogamous, including par- 

 thenogenetic, types of reproduction; while the Mendelian basis 

 would undoubtedly be the most satisfactory for types of plants 

 and animals that are continually mix-fecundated. We are 

 learning that there are an almost inestimable number of char- 

 acters in corn and that they may be quickly distributed to all 

 the representatives of the six species-groups by hybridization. 

 As an example: the kernel colors; red, yellow, blue and their 

 absence (white) are found in all of the groups. If we were to 

 give each distinct character, wherever we find it, a specific clas- 

 sification we should have many more species than we now recog- 

 nize. This is especially true with regard to economic plants. 



Such classification is desirable, however, and will soon be 

 needed from a Mendelian standpoint if from no other. As an 

 instance: we have evidence that there are more than twenty 

 reds or phases of red color in corn alone, and a system for their 

 classification is desirable. As was mentioned above, we have 

 isolated a dozen distinct tassel types, each possessing a number 

 of characters that may be easily redistributed by hybridization. 

 The inheritance of detail in both plants and animals is various: 



■"The Analysis of Characters in Corn and Their Behavior on Transmis- 

 sion," a paper submitted May 13, 1911, to the graduate school of the 



