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W. C. Etheridge 
of the oats grain; it is with certainty inherited; and therefore it is of par- 
ticular use in identification and description. To be sure, the color of a 
given variety is not absolutely stable, for under changes of environment 
it may pass into different tones of the same general hue, which, however, 
do not transgress the limits of the type. Nilsson-Ehle (1909) has reported 
the constancy of color inheritance in oats grains, although noting a slight 
variation under changes of environment — due, he believes, to the influ- 
ence of the soil. He finds the range in variation of dark-colored forms 
to be only from brown to black, and the reverse. Denaiffe and Sirodot 
(1901) also found color to be accurately inherited; but by the influence 
of environment, they said, black grains shade toward gray but never 
toward red, while brown grains shade toward red but not toward gray. 
Bohmer's investigation (1908-09) of dark-colored varieties gave results 
similar to those of Denaiffe and Sirodot; and in studying yellow varieties 
also, he found these to shade into various tones of yellow but never into 
white. Zade (1912), in noting the inheritance of characters in A. fatua, 
found the colors of the grain accurately reproduced. 
It appears, then, that the basic types of color in grains are not tran- 
sitional, but merely variable within certain limits; therefore it is only 
necessary to differentiate the colors properly in order to use them as 
means of distinguishing varieties. In doing this, however, one must not 
attempt to make fine subdivisions of color, for the distinction may be 
lost by variation within the type. The following classifications of color are 
given to illustrate the use of the character by different authors: 
Zade (A. fatua) 
Brown or black. 
Gray. 
White. 
Kornicke and Werner (various species) 
White. 
Yellow. 
Gray. 
Brown or red. 
Black. 
Nilsson (A. saliva and A. sativa orientalis) 
Light { jyj an y gjjg subdivisions in color between varieties of each class. 
