36 
BULLETIN 1074, U. S. DEPARTMENT OF AGRICULTURE. 
AVIDTH OF THE SHOULDER. 
The shoulder widths often differ from the glume widths. For this 
reason they are described separately, but on the same basis of meas- 
urement and by the use of the same terms, narrow, midwide, and 
wide (Fig. 5). 
SHAPE OF THE SHOULDER. 
Shoulder shapes are described in overlapping terms which allow 
for a considerable variation, which is nearly always present in the 
same spike. The terms used are want- 
ing, oblique, rounded, square, elevated, 
and apiculate. These shapes are shown 
in Figure 6. 
BEAK CHARACTERS. 
The word " beak " is used here for 
the short projection which terminates 
the keel of the glume. In some varie- 
ties it aproaches an awn in appearance. 
Scofield {173) first used the term beak, 
previous authors having referred to it 
. — Shoulder widths: a, Nar- j. j.i • x rri i i 
; 6, midwide ; c, wide. (Nat- ^^ a tooth or pomt. Ihe beaks vary in 
ural size and enlarged 3 diame- width, shape, and length. Thcse char- 
*^^^'^ acters are of considerable minor im- 
portance in identification and are used in the descriptions of the 
varieties. 
Fig. & 
row 
Fig. 6. — Shoulder shapes : a, Wanting ; h, oblique ; c, rounded ; d, square ; e, 
elevated; f, apiculate. (Natural size and enlarged 3 diameters.) 
WIDTH OF THE BEAK. 
Beak widths are described as narrow, midwide, and wide (Fig. 7). 
The average beak is only about 1 mm. wide, so the variations are very 
