CATALOGUE. 283 



Vilfa rigens, Trin. ? — Culm erect, 2-3° high, simple; leaves erect, 

 coriaceous, convolute, pungent; radical ones very long (1° or more); 

 panicle strict, erect, 1-1 £° long, interrupted below, the base frequently 

 included in the upper sheath; rays short, appressed, floriferous to the 

 base; spikelets 2" long, smooth; inferior glume one-fourth shorter than 

 the valve. Arizona, 1871 and 1872. 



Agrostis perennans, Tuck. 1 — Wet ground among the timber ; Colo- 

 rado, 1873 (1085). 



Agrostis scabra, Willd. — Low ground, Twin Lakes, Colorado, 1873 

 (1083); South Park, Colorado, 1873 (1084); Willow Spring, Arizona, 1874 

 (225). A very slender form. 



Agrostis exarata, Trin. (Watson's Botany 40th Parallel). — Twin 

 Lakes, Colorado, 1873 (1086); Camp Apache, Arizona, 1874(258). 



Agrostis verticillata, Vill— Root fibrous, culm procumbent, genic- 

 ulate at the rooting or ascending nodes, sheaths smooth or pubescent, ligule 

 1-2" long; leaves lanceolate-linear, 1-3' long, 1-3" broad, scabrous on 

 the margins and above, rarely glabrous ; panicle dense, 1-4' long, more 

 or less interrupted below ; rays more or less verticillate (3-8 together), at 

 the base branching and densely floriferous; glumes acute, nearly equal, 

 1 -nerved; palets subequal, awnless, £ to £ shorter than the glumes. — Camp 

 Bowie, Arizona, 1874 (449); Central New Mexico, 1871 (114). 



Agrostis vulgaris, With.— Twin Lakes, Colorado, 1873 (10a7); 

 probably introduced. 



Muulenbergia distichophylla, Kunth — Root firm, fibrous; culm 

 erect, 3-4° high, smooth, compressed, sheathed at the base by the dis- 

 tichous, coarse sheaths ; leaves very long, rigid, flat or somewhat involute, 

 compressed at the base, scabrous on the margin and keel; panicle often 

 1° or more long, contracted; rays solitary, thin, appressed, branched; 

 glumes subequal, scabrous on the back, shorter than the palets ; inferior 

 palet 3-nerved, short pilose on the margin below ; apex prolonged into a 

 bristle 2 J to 5" long ; superior palet 2-nerved. The awn is wanting in 

 some forms.— Rocky Canon, Arizona, 1874 (282) ; an awnless form (283). 



Muulenbergia Texana, Thurb. (Synopsis of Flora of Colorada, p. 

 144). — Arizona, 1871 ; Cienega, Arizona, 1874 (574). 



