162 
W. C. Etheridge 
glaucous at period of full heading, short to long (20-30 mm.), 9-10-nerved; 
grains white to yellowish white, elongate, outer grains 16-19 mm. long, 
long-pointed; lemma of the outer grain glabrous, with 7 obscure nerves; 
awns rare; basal hairs usually absent, if present few, short, and weak; 
rhachilla of the outer grain short to medium long (2-3 mm.), glabrous 
or in some cases carrying a few short, fine hairs. Plants 10-15 dm. tall; 
late in maturing. 
Specimens of the variety White Tartar were found under the following 
additional names: x\merican Banner, Danish, Dun, Great Northern, 
Lincoln, Long's White Tartar, Minnesota 271, Pringles Progress, Read's 
Green Mountain, Tartarian, White Russian. 
Green Mountain (Plate XXII, 4, and fig. 33).— Similar to White Tartar, 
with the following exceptions: awns numerous in the panicle, usually 
present in each spikelet; 3-grained spikelets numerous. 
Specimens of the variety Green Mountain were found under the following 
additional names : Read's Green Mountain, White Russian, White Tartar. 
CONCLUSION 
In the foregoing classification fifty-five varieties have been distinguished 
within the three common specific groups A. sterilis, A. sativa, and A. 
sativa orientalis. Within each group the varieties are systematically 
arranged with respect to such morphological differences as appear to best 
fulfill the twofold requirement of constancy in inheritance and ease of 
observation. It cannot be said that the arrangement is according to the 
strictest order of relationship, for, as previously explained, the modifi- 
cations in the structure of cultivated plants do not permit a strictly logical 
taxonomy. Thus a group of varieties having dark-colored grains may 
include forms that are actually more closely related to certain varieties 
within a group of light -colored grains than to other members of the dark- 
colored group. But in a classification which, like the present one, deals 
with a large number of closely related and interrelated forms, the actual 
degree of relationship must, in the arrangement of varieties, be sub- 
ordinate to expediency in identification — which purpose the classification 
of varieties of cultivated plants chiefly serves. 
While the classification presents its arrangement of varieties according 
to the modifications in their characters as exhibited in the present environ- 
ment, the arrangement is based mainly on a fundamental morphology 
