CHLORIDEZ 217 
1 terminal, the other a short distance below, both nearly sessile 
and more or less ascending, about an inch long, somewhat curved; 
spikelets sessile, about 5 mm. long, densely crowded on one side of 
the pubescent rachis; glumes narrow, the upper villous and more or 
less beset with dark papille, the lemma _ pubescent; rudiment 
rounded, 3-awned. The end of the rachis does not project beyond 
the spikelets. The spikes turn with the wind like vanes. In the 
less arid portions of the Great Plains this species forms a rather 
compact sod; in drier regions the tufts are isolated. This is some- 
times called blue grama but to stockmen it is usually known merely 
as grama. It is the most important economic species of the genus, 
ranging on the Great Plains from Manitoba to South America and 
westward into New Mexico, Arizona and southern California. 
Bouteloua hirsuta Lag. Black grama. Resembles the preceding 
but differs in the prolongation of the rachis 
as a naked point 5 to 8 mm. beyond the 
spikelets, and in the more hairy second 
glumes with prominent black papilla. The 
range is about the same as that of the pre- 
ceding but does not extend so far north. 
Bouteloua curtipendula (Michx.) Torr. 
Tall or Side-oat grama. Culms 2 to 3 feet 
high, the spikes numerous, 30 to 50, 
arranged, by twisting of the peduncles, 
along one side of the upper part of the 
culm for 6 to 10 inches, about 1% inch 
' long, the spikelets appressed, 5 to 8 in 
each spike. Prairies and plains, from 
Ontario to Montana and south through 
Mexico to South America. 
Fic. 48. Bulbilis dactyloides. Staminate plant, 
X 4; spikelet, x4. 
