236 A TEXT-BOOK OF GRASSES 
Key TO THE GENERA OF HoRDEX 
A. Spikelets more than 1 at each node of the rachis. 
B. Spikelets 3 at each node of the rachis, 1- 
flowered, the lateral pair pedicelled, usually 
POUUCEE. 2 cae 5 distentak tear asi Sie at eeisele cake HorDEUM 
BB. Spikelets 2 at each node of the rachis, 2- to 6- (Par. 268). 
flowered, all alike. 
c. Glumes none or reduced to short bristles; 
RMS WE Rey OE on she i eg Bread ee HyYsTrIx. 
cc. Glumes usually equaling the florets; spikes 
dense. 
Dp. Rachis continuous; glumes broad or 
MATEOMT: CEE Fy 8 68 hho Fs dt ate chap hs ELYMUS 
DD. Rachis_ disarticulating at maturity, (Par. 269). 
glumes slender, extended into long 
awns, these and the awns of the 
lemmas making the spike very bristly.SITANION. 
AA. Spikelets solitary at each node of the rachis. 
B. Spikelets placed edgewise to the rachis; 
glume 1 except in the terminal spikelet. 
c. Spikelets several-flowered............... LoLiuM 
cc. Spikelets 1-flowered. Introduced on the (Par. 261). 
APIO WRORE Ne et a sk Pie ts bao ears MoNERMA. 
BB. Spikelets placed flatwise to the rachis; 
glumes in pairs. 
c. Spikelets 1-flowered; spikes slender, terete. 
By Leminan awhile, 65. HS oss Sate LEPTURUS. 
pp. Lemmas awned. Pacific coast......... ScRIBNERIA. 
cc. Spikelets 2- to several-flowered. 
p. Plants perennial (as to species of the 
Winter. HUAECE GL ose tee + Le ate AGROPYRON 
pp. Plants annual. (Par. 262). 
E. Glumes ovate, 3-nerved............. TRITICUM 
(Par. 263) 
EE. Glumes subulate, l-nerved.......... SECALE 
(Par. 267). 
261. Lolium L—Rye-grass. A small genus of temper- 
ate Eurasia. Spikelets several-flowered, somewhat resem- 
bling those of Festuca, the lemma often awned. The 
genus can be easily distinguished by the position of the 
spikelets, edgewise to the rachis. The second glume being 
next the rachis is usually suppressed but is present and 
equal to the first in the terminal spikelet. Two closely 
related species are used for lawns, meadows and pastures. 
