[04 
W. C. Etheridge 
group all grains of the spikclct are awned. Roberts and Freeman (1908), 
on investigating the 1 'degeneracy" of the Texas Red variety, found merely 
a mixture of two distinct forms. 
In systematizing cultivated oats the awn is a character of much taxo- 
nomic value. Kornicke and Werner (1885) made the primary division of 
their principal group according to the number of awns in the spikelet. 
Thus, varieties with awnless or one-awned spikelets were separated from 
those with two-awned spikelets; and for the distinction of individual 
varieties of the former group the presence or the absence of awns was 
coordinated with the color of grains. Denaiffe and Sirodot (1901) fre- 
quently used the presence and the form of awns as secondary characters 
for the distinction of groups. With respect to awns, they divided the 
grains into three groups: (1) awnless; (2) outer grains with coarse, 
deciduous awns; (3) outer grains with finer, persistent awns. Atterberg 
(1891), Nilsson (1901), and Bohmer (1911) made no use of the awns in 
classification, although Bohmer (1908-09) believed that varieties might 
be grouped according to the classes of Denaiffe and Sirodot, even though 
their group relationship would often be uncertain. Broili (1910) believes 
the awn to have little or no systematic value. 
In the present classification the presence or the absence of awns has been 
regarded as a character of secondary importance and frequently used in 
that order. Geniculate awns appear often only in a few half-wild varieties, 
but in such cases they are recognized as a distinguishing character. No 
statistical studies have herein been made of the inheritance in frequency 
of awns, but in respect to the actual presence or absence of awns, together 
with their form, the varieties under study have by observation remained 
constant. 
FORM OF THE GRAIN 
A differentiation of the form of grains, including plumpness, or fullness, 
size, and specific outline, has been a prominent feature of most of the 
previous systems of classification. Atterberg (1891) based his classifi- 
cation mainly on the size (weight) of the grains, and on the following 
shapes: pointed, short, barley-like, and full, or plump. Denaiffe and 
Sirodot (1901) incorporated in their system the method of Atterberg, 
and in addition employed other shapes of the grain, described as slender 
and duckbill. Nilsson (1901) and Bohmer (1911) made the form of the 
grains subordinate to the character of the panicle; and the latter author, 
