WOOTON AND STANDLEY—FLORA OF 
Spikelets oval or obovate; fruit chartaceous, 
rigid, the lemma margins inrolled, not 
hyaline, 
First glume present; spikelets panicled, 
rarely in racemes........-.-....--- 17. 
First glume obsolete; spikelets in racemes. 
Spikelet with a swollen ringlike cal- 
lus below; fruit awn-tipped. ..15. 
Spikelets without a callus; fruit not 
awned............-.----------16., 
Tribe V. PHALARIDEAE. 
Panicles dense and contracted; sterile lemmas minute.21. 
Panicles loose and open; sterile lemmas inclosing 
staminate flowers.........---ee0e-- eee eee eee ode 
Tribe VI. AGROSTIDEAE. 
Lemmas indurated at maturity, closely inclosing the 
grain, 
Spikelets in pairs, one perfect, the other staminate 
or sterile (in spikelike panicles)............ 23. 
Spikelets not in pairs, all perfect. 
Lemma 3-awned (2 of the awns sometimes very 
Lemmas l-awned or awnless. 
Awns twisted and bent .................- 25. 
Awns not twisted, or wanting. 
Lemmas narrow; awns, when present, 
persistent. ..........2...--+--- 26. 
Lemmas broad; awns deciduous..... 27. 
Lemmas usually thin at maturity, at least more delicate 
than the glumes; grain loosely inclosed. 
Glumes conspicuously compressed-keeled; panicle 
dense and spikelike, cylindrical. 
Rachilla jointed above the glumes, these per- 
sistent; lemma awnless......... ..28,. 
Rachilla jointed below the glumes, these fall- 
ing with the spikelets; lemma awned. .29. 
Glumes not compressed-keeled; panicles mostly 
open and spreading, rarely crowded and 
spikelike. 
Panicle spikelike, elongated, 30 cm. long or 
Panicle not elongated. 
Spikelets articulated below the glumes, 
falling entire. 
Glumes awned; panicles dense...... 33. 
Glumes awnless; panicles open...... 34. 
Spikelets articulated above the glumes, 
these persistent after the fall of the 
florets. 
NEW MEXICO. 45 
Panicum (p. 56), 
ERIOCHLOA (p. 54). 
PAsPALuUM (p. 55). 
PHALARIS (p. 61). 
SAVASTANA (p. 61). 
Lycurus (p. 62). 
. ARISTIDA (p. 62). 
Srrpa (p. 65). 
MUHLENBERGIA (Pp. 68). 
Oryzopsis (p. 72). 
PHLEUM (p. 73). 
ALOPECURUS (p. 73). 
. Eptcamres (p. 74). 
PoLyPoGon (p. 77). 
Cinna (p. 78). 
