356 GRASS FAMILY 



1. Panicle narrow or spike-like, the short branches 



erect or ascending 



a. Lemma with an awn usually 1-2 cm. long 



( 1 ) Panicle dense ; lemma with a tuft of basal 



hairs its own length M. comdta 



(2) Panicle narrow, not dense and spike-like; 



lemma without a tuft of basal hairs M. gracilis 



b. Lemma with an awn 1-2 mm. long, or awnless 



(1) Stems with scaly root-stalks 



(a) Glumes about equal, much longer than 



the lemma M. racemosa 



(b) Glumes somewhat unequal, the longer 



equalling the lemma M. mexicdna 



(2) Stems without scaly root-stalks 



(a) Panicles 1-2 in. long, upper glume 3- 



nerved M. iiliciilmis 



(b) Panicles 2-4 in. long; upper glume 1- 



nerved M. Wrightii 



2. Panicle open, the branches spreading, often hori- 



zontal 



a. Lateral branches of the panicle panicle-like ; 



spikelets 3 mm. long; awn 1-2 mm. long M.pungens 



b. Lateral branches of the panicle raceme-like ; 



spikelets 2 mm. long ; awn 2-6 mm. long M. gracillima 



Munroa Torrey 1856 Munroa 



(Named for Munroe, an English botanist) 



PL 45, fig. 25. 



Spikelets 2-5-flowered, in clusters of 3-6 in the axils of the floral leaves ; 

 glumes lanceolate, acute, 1-nerved ; lemma larger, 3-nerved, 3-toothed at 

 apex with tufts of hairs near the middle, palet narrow, acute; low grass with 

 short spiny-tipped leaves. 

 Stems tufted, 2-8 in. high ; leaves an inch long or less, 



spiny-tipped M. squarrosa 



Oryzopsis Michaux 1803 Mountain Rice 

 (Gr. oryza.y rice, apsis, likeness) 

 ' PI. 46, fig. 19. 



Spikelets 1-tiowered, in panicles; glumes 2, equal or unequal; lemma 

 lemma broad with a terminal awn, palet narrow ; perennial. 



