The Grasses and Grass-Like Plants 

 of New Mexico 



Key to the Families he;;k Tkkated 



Perianth rudimentary or degenerate. Its mem- 

 bers being mere bristles or scales; flowers 

 in the axils of dry chaffy scales or glumes. 

 Leaves 2 -ranked; sheaths with the margins 

 not united; stems mostly hollow and 



jointed; fruit a grain. Family I. GRAMINEAE. 



Leaves 3-ranked; sheaths with margins 

 united; stems solid, mostly not jointed; 



fruit an achene. Family II. CYPERACEAE. 



Perianth of two distinct series, both chaffy and 

 much alike but not glumaceous: fruit a 

 capsule. Family III. JUNCACEAE. 



I. GRAMINEAE. Tpie Grass Family 



Fibrous rooted annual or perennial herbs with hollow cylin- 

 drical stems with leaves in two rows their blades long and narrow 

 and parallel veined, their bases fonning an open sheath around the 

 stem; inflorescence a more or less branched panicle composed of 

 small spikelets of flowers subtended by two empty glumes: spike- 

 lets 1- to several-flowered: flower consisting of 2 glumes (the 

 flowering glumes) usually 3 stamens, a two-parted pistil with 

 mostly feathery pisti's and a single ovary which becomes the grain 

 or "seed." 



IvEY TO THE TUIBES 



Spikelets falling from the pedicels entire. 



naked or inclosed in bristles or bur-like 



involucres, 1-flowered or if 2-flowered the 



lower flower staminate; no upper empty 



glumes: racliilla not extending above the 



upper glume. 



Flowering glumes hyaline, thin, much more 



delicate in texture than the empty 



glumes. 



Spikelets in pairs, one sessile, the other 



pedicellate. TrilH- I. Andropoo 



Spikelets not in pairs, (Alopecurus, Poly- 



poffon, Cinna, etc.) Tribe II. Zotsieae. 



Flowering glume, at least that of a perfect 

 flower, similar in texture to the empty 

 glumes, or thicker and firmer, never 

 hyaline and thin. 



Flowering glumes membranous; the first 

 emptv glume usually larger than the 

 rent. ' Tribe V. Agrostideax 



