SPERMATOPHYTA—GRAMINEAE— GRASSES 353 



Fig. 144a. Long-awned Poverty Grass 

 {Aristida tuberculosa). a, Spikelet with lower 

 glume; b, flowering glume with divergent long 

 awns. (U. S. Dept. Agrl.). 



Fig. 144b. Short-awned Poverty Grass. {A. 

 basiramea). Occurs in sandy and gravelly soils. 

 (U. S. Dept. Agrl.). 



nearly equal, 12 lines long, awn-pointed; flowering glume about 10 lines long, 

 twisted above to the division of the awns, and with a densely barbate sharp- 

 pointed callus; awns nearly equal, divergent or reflexed, l%-2 inches long, dis- 

 tinctly articulated with the glume. 



Injurious properties.. .The sharp pointed callus slightly injurious in the 

 same manner as Stipa. 



7. Stipa, L. 



Perennial grasses with 1-flowered spikelets, flower falling away at maturity 

 from the membranous, persistent, lower glumes, fertile glumes coriaceous, 

 cylindrical, involute, and embracing the smaller palet and cylindrical grain ; a 

 long twisted or spiral awn jointed with the apex, the base consisting of a beard 

 and sharp pointed callus; stamens generally 3; stigmas plumose. 



