CLASSIFICATION" OF AMERICAN WHEAT VARIETIES. 41 
The texture classes used here are two — kernels soft to semihard 
and kernels semihard to hard. Here, as with size, overlapping class 
limits were found to be necessary. In general, all wheat varieties can 
be classed readily in one or the other of these two groupings. In de- 
scribing specific samples and in individual description of varieties, 
three classes are used separately, as soft, semihard, and hard. A soft 
v>'heat is one which, when normally developed, has an endosperm en- 
tirely soft, mealy, or starchy. A hard kernel, when normally devel- 
oped, has a corneous, horny, or vitreous endosperm throughout. A 
semihard kernel has an endosperm which is intermediate between the 
two. Cross sections of kernels showing differences in texture in both 
normal and yellow-berry kernels are shown in Plate A^LI, Figure 2. 
The upper series of kernels shows normal development and the 
lower series the yellow-berry condition. In Figure 2 a, (1) and 
(2) represent different degrees of softness and (3) the semihard con- 
5HORT TO MIDLONG m.DLONG TO LONG 
■* "-' /-omm. 6.5 TO lO mm. 
Fig. 11. — Diagiam showing measurements of kernel lengths : 
Above, major characters; below, minor characters. (Enlarged 
10 diameters.) 
dition in the soft class. In Figure 2, 6, (4) shows the semihard condi- 
tion and (5) and (6) different degrees of hardness. 
The species Triticuni, duruvi was so named by Desfontaines {79) 
because of the hardness of the kernels. Metzger {II^S) divided the 
white-kerneled wheats into two groups on the basis of texture, the 
starchy ones being considered as yellow. Koernicke and AYerner {133) 
described the wheat kernels of different varieties as being entirely 
mealy, nearly entirely mealy, mostly meal}^, partly mealy, partly 
glassy, mostly glassy, nearly entirely glassy, and entirely glassy. The 
texture of the same variety varied in different seasons. These authors, 
as well as Eriksson {88), Fruwirth {92)^ and Howard and Howard 
(i^i, p. 232), conclude that kernel texture is useless as a varietal 
character and that it depends on environment. Hayes, Bailey, Arny, 
and Olson {105) suggest the terms corneous, subcorneous. substarchy, 
and starchy for describing the texture of the wheat kernel. The 
writers have concluded that because of the variability in texture 
under different environments one can separate varieties of wheat 
accurately into only two classes and fairly accurately into three 
classes. Soft-kerneled varieties grown under very dry conditions 
will sometimes become brittle and slightly subcorneous. When hard- 
kerneled varieties are grown under humid conditions or in soil de- 
ficient in nitrogen they sometimes become starchy, semistarchy, or 
