No. 7. 

 ARISTIDA PURPUREA Nutt. 



Plant annual or short lived perennial, often purplish, especially in the inflor- 

 escence. 



Culms tufted, erect, slender, not branching, nearly smooth, 1 to 2 feet tall. 



Leaves; radical and of radical shoots with narrow, close sheaths and slender 

 involute blades, 4 to 10 inches long; of culm 3 or 4; lower sheaths longer than inter- 

 nodes, upper ones much shorter, close, smooth ; blade involute, hispid above, 3 to 

 6 inches long ; ligule a line Of fine short hairs, somewhat hairy at the sides. 



Inflorescence rather loose, narrow, erect or slightly nodding panicle, 4 to 6 

 inches long; branches 2 or 3 at each node, unequal, the lower 1 to 2 inches long, 

 naked below, each bearing 2 to 5 pedicellate or nearly sessile spikelets. 



Spihelets narrow, 1-flowered, 5 to 6 lines long; first glume narrowly lance-lin- 

 ear, emarginate, mucronate, rounded, hispid on keel, 1-nerved, 4 to 4i lines long: 

 second glume same but nearly 2 lines longer; stipe hairy, i line long; floral glume 

 linear-lanceolate, rounded, slightly hispid on the nerve above, 4 lines long, termi- 

 nating in 3 separate, slender, minutely hispid awns 1 to 2 inches long; palet obo- 

 vate, thin, -J- to f line long. 



Plate VII: a, spikelet twice as large as natural size. 



Abundant on plains and ridges, in several varieties, from Texas to British 

 America. It is the earliest available grass for cattle in the spring, but of little 

 value when mature. 



