CLASSIFICATION OF A]\IEPJCAN WHEAT VARIETIES. 
43 
as ovate. An elliptical kernel outline is one the length of which is 
more than twice the width and which has sides somewhat curved 
and both ends rounded. An oval kernel outline is broader, like the 
ovate, but with both ends of nearly equal width. The three shapes, 
ovate, elliptical, and oval, are shown in Figure 12, «., &, and c. 
Modifications of these shapes are indicated by describing kernels as 
narrowly or broadly elliptical, ovate, or oval, as the case may be. 
A few varieties, as Baart, show other characteristic shapes, which are 
given in the descriptions of these varieties. 
Most kernels are classified as ovate, but in a few varieties a consid- 
erable portion of the kernels may have one or the other of the shapes 
just noted. The shape of the wheat kernel is influenced by the posi- 
tion in the spikelet, the position in the spike, and the degree of 
plumpness. Boshnakian (4^) has shown that spikelet characters 
which affect the shape of the wheat ker- 
nel are mainly: "(1) The stiffness of 
the glumes, (2) the size and shape of 
the space in which the grain develops, 
(3) the number of grains in the spikelet 
and their position, (4) the density of the 
head, (5) the pressure caused by the 
growth of different parts of the head, 
and (6) the species which produces the 
kernel." The kernels from the base or 
tip spikelets on the spike are shorter in 
proportion to width than the others. 
The kernels from club wheat or from 
the tip spikelets of clavate spikes of common wheats are usually 
laterally compressed or "pinched." Shrunken kernels usually have 
an elliptical shape because of being narrow. As the width of a 
kernel of wheat depends largely upon the degree of development of 
plumpness, this character has very little taxonomic value. 
The tip or brush end of nearly all varieties is rounded, but the 
kernels of a few varieties, in which the tips are square rather than 
rounded, as seen from the dorsal view, are described as truncate. 
Kernels of a few varieties have acute or pointed tips, as seen in both 
dorsal and lateral views, and such tips are described as acute. 
The shape of the kernel as seen in the lateral view is important in 
only a few varieties. Many varieties, especially durums and emmers, 
are more or less keeled on the dorsal surface. Normally the kernels 
of wheat, in clorso-ventral diameter, are thickest near the base, just 
above the germ. In a few varieties the kernels are strongly elevated 
on the dorsal side of this basal portion and then are popularly 
known as " humped." That term is used in describing such kernels. 
Fig. 12. — Kernel shapes : a, Ovate ; 
6, elliptical ; c, oval. (Natural 
size and enlarged 3 diameters.) 
