GR AMINES. (GRASS FAMILY.) 413 



flowering glume exsertly awned on the back at or below the middle. — 

 Found everywhere, aud very variable, the mountain forms especially bearing 

 many names. Known as " Brown Bent Grass." 



20. CINNA, L. Wood Reed Grass. 



A perennial grass, with simple and upright somewhat reed-like stems, 2 to 

 7 feet high, bearing an ample compound terminal panicle, its branches in 

 fours or fives ; the broadly linear-lanceolate flat leaves with conspicuous 

 ligules. 



l. C. arundinaeea, L., var. pendula, Gray. Stem smooth, with 

 conspicuous brownish nodes : leaves rough on both sides and margins : pani- 

 cle 8 to 12 inches long, drooping at apex, the capillary rays clustered, distant, 

 flexuose, very unequal, the longer flower-bearing above the middle, very sca- 

 brous. — California and northward, thence eastward through Montana to the 

 northern border States. 



21. AMMOPHILA, Host. 



Perennials, with stout stems from thick running rootstocks. This is repre- 

 sented in Gray's Manual by the Calamovilfa and Ammophila sections of 

 Calamagrostis. 



1. A. longifolia, Benth. Stems 1 to 4 feet high: leaves rigid, elon- 

 gated, involute above and tapering into a long thread-like point : branches 

 of the pyramidal panicle smooth : the copious hairs more than half the 

 length of the naked flowering glume and palet. — Calamagrostis longifolia, 

 Hook. From Colorado northward, thence eastward to Michigan and Illinois. 



22. DEYEUXIA, Clarion. Reed Bent Grass. 



Perennials with running rootstocks and mostly tall erect and rigid stems. 

 This genus includes all the species of Calamagrostis in the section Deyeuxia. 

 * Panicle loose and open. 



1. D. Canadensis, Beauv. Stems tall, erect, smooth, 3 to 5 feet high: 

 leaves about a foot long, flat, minutely scabrous : panicle 4 to 6 inches long, 

 oblong, the common axis and rays scabrous: spikelets l£ to If lines long: 

 outer glumes lanceolate, acute : flowering glume nearly as long, surrounded by 

 copious white hairs, and awned on the back from near the middle with a very 

 delicate bristle not much stouter than the hairs, and usually barely equalling 

 or rarely slightly exceeding the palet. — Calamagrostis Canadensis, Beauv. 

 From New Mexico northward and across the continent. 



2. D. Langsdorffii, Trin. Closely resembling the last, but distin- 

 guished by its longer spikelets (2 to 3 lines), attenuate-acuminate outer glumes, 

 which are often cinereously strigose-pubescent, and its stouter and usually 

 exserted awn. 



# * Panicle narrow, the erect branches oppressed after flowering. 



3. D. Lapponica, Trin. Stem about a foot high : radical leaves nearly 

 as long ; stem leaves much shorter and divergent, all convolute, rigid and strongly 



