A Classification of the Varieties of Cultivated Oats 107 
Bohmer (A. saliva and A. sativa orientalis) 
Light-colored : 
White, white-yellowish. 
Yellowish, yellow. 
Dark-colored : 
Black, brown, red, gray. 
Denaiffe and Sirodot (A. sativa and A. sativa orientalis) 
Light-colored : 
White, white-yellowish, yellow. 
Dark-colored : 
Black, red, gray. 
In the present classification, several large groups of varieties are pri- 
marily divided, with respect to color, merely as dark-colored (black, 
brown, red, gray) and light-colored (white, yellow), but further division 
on the basis of color is made only in groups that have been reduced by 
separations according to differences in other characters. This apparent 
reluctance to make immediate further separation on the basis of color is 
not due to lack of faith in the stability of the character, but merely because, 
for convenience in classification, the use of other characters is expedient. 
In three years of investigation the colors of grains have been found con- 
stant within the limits of the classes outlined in this paragraph. With 
respect to variability of color types, the observation may be added that 
from year to year unlike weather conditions at the time of ripening will 
cause slight variations in the color of a given variety. Thus, if the matur- 
ing period is during bright, dry weather, the grains are brighter and more 
pronounced in color than if the maturing period is during wet and cloudy 
weather. Black or yellow grains that ripen under the latter atmospheric 
conditions show a tendency toward smoky brown and pale yellow, although 
never becoming reddish brown or white. The stage of maturity at which 
the grain is harvested also affects its shade of color, all colors being more 
pronounced when the grain is thoroughly matured than when it is either 
slightly immature or allowed to weather after the maturation period 
has passed. 
dimensions of the grains 
Although Denaiffe and Sirodot (1901) minutely characterized the 
grains by absolute measurements and often used the same feature to 
distinguish secondary groups of varieties, other investigators, while 
including the dimensions of grains in the detailed descriptions of varieties, 
