232 



POACE^E. 



]^ow Mexico, IIV/V//!/ 19!t7; Ca\\(on\in, Lcnimon 2023; Arizona, 

 Prhif/h: 



Tim liJis hoon found in partial simile of calcareous cliffs. 

 New Mexico to Arizona. 



48. (110). Eriocoma Nutt. (Jen. N. Am. PI. 1 : -10 (1818). 

 Panicle few-llowered with still", sleiuler, llexuosc, dichotomously 

 branched rays. Spikelets e^olitary, 1 -flowered. Empty glumes 

 membranous, alternate, rostrate, first 3-, second 5-nerved. floret be- 

 coming coria. 's, ventricoso, clothed with long white silky hairs, 

 bearing at the base a short, stout, chisel-shaped callus and at or 

 just below the apex a short straight or curved, obscurely trique- 

 trous, caducous awn. Lodicules '.], as long as the ovary. Stamens 3. 

 1. E. membranacea (i*ursh.). S/i/xi nieni/tniiincm Pursh. Fl. 

 Am. Sept. 3:728 (1814). K hynioiuides \\. & S. Syst. 2:339 

 (1817). Eriocoma ruspidata ^wii. iWn. i: 40(1818). Milium 

 cuspidal urn Spreng, Syst. 1 : 251 (1825). rraclnie Janata 'Yv'm. 

 Act. Pctrop. 12(5 (1834). (h\)/y,opt>is cnspidata I?enth. Vasey, 

 Gram. U. S. 23 (1883). 



Culms hard, smooth or scabrous, nearly solid. 30-GOcm. high. 



Sheaths scabrous or smooth, 

 mostly shorter than the inter- 

 nodes; ligule acute, 3-5 mm. 

 long; l)lades scabrous, narrow, 

 involute, the lower often equal- 

 ling the culm, the uppermost 

 very short or nearly as long as 



the ])anicle. Panicle often in- 

 cluded at the base, diffuse, 12- 

 15 cm. long; the rays llexuose, 

 each bearing one si)ikelet, whicli 

 is oval, acute, becoming ventri- 

 cose, pubescent, G-7 mm. long; 

 empty glumes subequal, attenu- 

 ate-rostrate, 1-2 nerves at the 

 base on either side of the prominent mid-neive; floret hard, oval, 

 3-4 mm. long, densely clothed with white hairs, often extending 2 



Fio. 43. — Kriocoma memhranacca . A 

 spikelet ; «, Horot. (Uichurdson.) 



