A Classification of the Varieties of Cultivated Oats 117 
node, but fuse with the stem until finally they issue from the knee-like 
bend, which thus becomes nominally the first node of the panicle. The dia- 
phragm of the first node is usually, but not always, absent. In some cases, 
when the first node, or bend, is fused with the outlying node, the diaphragm 
is present, although often more or less defective; but in such cases the 
diaphragm thus appearing is doubtless a part of the usual outlying node. 
Without special histological studies of its structure, little can be said 
of this peculiarity of the rhachis, although for its present taxonomic use 
the foregoing general 
description is suffi- 
cient. Neither the ab- 
normal node nor the 
extremely flexuous 
form of the rhachis 
has been used in pre- 
vious classifications of 
varieties of oats, al- 
though Denaiffe and 
Sirodot (1901) have 
described and illus- 
trated the former. 
For a few varieties of 
the present classifica- 
tion, however, these 
exceptional characters 
provide a marked dis- 
tinction, and for that 
purpose they are used. 
Fig. V, 
THE ABNORMAL NODE IN CERTAIN VARIETIES OF 
AVENA SATIVA ORIENTALIS 
A, Section of stem and rhachis showing the lowest whorl of branches 
issuing from a bend in the rhachis at which the nodal diaphragm is 
wanting, while the true node, branchless, lies some distance below; B, 
section of stem and rhachis showing the lowest whorl of branches aris- 
ing from a normal node at whicft the nodal diaphragm is well developed 
THE LEAVES 
In the leaves of cultivated oats the varietal differences are found in 
their margins and dimensions. Kornicke and Werner (1885), in describing 
varieties, mentioned the ciliate margins and the length and width of 
leaves, but they did not use these characters in classification. Among 
certain groups of varieties, however, the leaves differ greatly. Thus 
there is a marked distinction between the fine, narrow leaves of Sixty-Day 
and Kherson, and the wide, coarse leaves of Storm King and Sparrow- 
