DESCRIPTIONS OF TRIBES AND GENERA. 



183 



1. Empty glumes distinctly keeled only in the 

 upper half, rounded or only slightly keeled 

 in the lower half. 



* Spikes long, more or less loose, some- 

 what dorsally compressed. 



a. Tr. sat. vulgare. 



** Spike short, dense, distinctly four- 

 sided. . . . ft. Tr. sat. compactum. 

 2. Empty glumes sharply keeled at the base. 



* Fruit short, thick, not compressed, 

 broadly truncate above. 



y. Tr. sat. turgidum. 



** Fruit oblong, narrower, somewhat lat- 

 erally compressed, and somewhat acu- 

 minate 3. Tr. sat. durum. 



Tr. sat. vulgare (Tr. vulgare Vill.), common 

 wheat (Figs. 96, 

 97). The princi- 

 pal sub-varie- 

 ties are awnless 

 and bearded 

 (awned) wheats, 

 with naked or 

 hairy, whitish, 

 bluish, black- 

 ish, or reddish 

 spikes. It has 

 been known 

 from most an- 

 cient times 

 (grains found in 

 Egyptian Pyra- 

 mids) ; is gener- 

 ally cultivated 

 as far north as 

 its cultivation is 

 possible (Nor- 

 way, 69 N. Lat., 

 Alps at 1400 

 metres altitude), and its culture is very import- 



FIG.%. Common Bearded FIG. 97. 2V. 

 Winter Wheat. Triti- sativumvul- 

 cum sativum vulgare. gave muti- 



cum. 



