150 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Blades lanceolate; first glume not more than one- 
third as long as the spikelet. 
Culms crisp-puberulent; blades rarely over 
1 cm. wide; spikelets about 2.5 mm. 
TOWRA ai/e Rt arose LS ea ey Soy Nee ane 183. 
Culms glabrous or obscurely puberulent; 
blades usually 1.5 cm. or more wide; 
spikelets 2.7 to 3 mm. long.......... 184. 
Spikelets not over 2.3 mm. long; blades not cordate, usu- 
ally less than 1 cm. wide. 
Blades conspicuously ciliate, soft and lax, crowded 
ait Ue) DASH Mites te RGN EE IN ee eee 88. 
Blades not ciliate or so only at base, not crowded 
at the base of the culm. 
Blades not over 6 mm. wide; plants not branch- 
ing or rarely branching from near the 
ASC A Sa ERY earns tai UAC A 8 te en a 85. 
Blades 7 mm. or more wide; plants branching 
from middle and upper nodes. 
Primary blades spreading; panicle purplish; 
fruit exposed at summit..........-- 107. 
Primary blades erect; panicle green; fruit 
COVCTCOE ANN yee tia Par ey Ste eeene ee 108. 
Spikelets not over 1.7 mm. long. 
Culms crisp-puberulent; spikelets turgid............-.-- 147. 
Culms glabrous. 
Blades white-margined, firm. 
Blades puberulent beneath, often above..-.-...-. 152. 
Blades glabrous. 
Uppermost blades much reduced; culms 
branching from lower nodes only, the 
branches repeatedly branching... - . 153. 
Uppermost blades about as long as the others; 
culms bearing short branches from 
middle and upper nodes..-.....------ 154. 
Blades not white-margined or very obscurely so (or 
if white margin is evident, spikelets only 1.1 
mm. long). 
Culms branching only at base; plants soft, light 
STEEN 412 Sea > Ce Babee ee ee Gs 
Culms branching at the nodes. 
Spikelets 1.1 mm. long; winter blades bluish 
greeny Not glossy eee eee 156. 
Spikelets 1.3 to 1.5 mm. long. 
Blades involute, faleate, with long stiff 
hairs on margin near base; plants 
Bb amd sways me see eines 162. 
Blades not involute or at tip only, not 
falcate. 
Plants bright green; winter blades 
IP: 
. ashei. 
commutatum. 
. ciliatum. 
. Werner. 
. clutet. 
. boreale. 
. columbianum. 
. tenue. 
. albomargina- 
tum. 
. trifolium. 
. vernale. 
. concinnius. 
. breve. 
conspicuous, glossy green. ..155. P. flavovirens. 
Plants olive; winter blades not con- 
spicuous nor glossy...------ 157. P. ensifolium. 
