68 Graminaceae 
BOUTELOUA GRAMA-GRASS > 
Annual or perennial (ours), slender. Leaf-blades narrow, flat or convolute. Spike- 
lets 1—-2-flowered, sessile, densely crowded in 2 rows on | side of a flattened spike- 
rachis; spikes solitary or in a raceme; rachis projecting beyond the base of the upper 
spikelet; rachilla jointed above the glumes, with I—-3 lemmas or bristles or rarely 
staminate flowers above the perfect flower. Glumes narrow, acute, keeled, equal or 
unequal (ours). Lemma wider than the glumes, 3—5-toothed or -cleft at the apex and 
3 of the divisions usually awned (ours), 3—5-veined. Palet narrow, hyaline, entire 
or Z-toothed, 2-keeled, about as long as the lemma. Stamens 3. (Honor of C. 
Boutelou, a Spanish agriculturist.)  E. 
B. oligostachya Torr. 
BECKMANNIA 
Perennial, erect, rather tall. Leaf-blades flat. Spikelets 1-flowered (ours) or 2- 
flowered, broad, flattened, subsessile, closely imbricate in 2 rows on 2 sides of a 
3-angled rachis thus forming short slender spikes; spikes arranged in a terminal long 
narrow panicle; rachilla jointed beiow the glumes. Glumes chartaceous, subequal, boat- 
shaped, flattened, obtuse or bluntly pointed, scarious-margined. Lemma _ lanceolate, 
acuminate, thin. Palet hyaline, 2-keeled, nearly as long as the lemma. Stamens 3. In 
wet places. (Honor of J. Beckmann, a German botanist.)  E. 
B. erucaeformis Host. (Slough-grass) 
ELEUSINE 
Annuals, coarse, tufted or creeping. Spikelets several-flowered, awnless, flat, 
imbricate in 2 rows along | side of a rachis thus forming a spike; spikes arranged digi- 
tately at the end of the stem or somewhat racemose; rachis not extending beyond the 
upper spikelet; rachilla jointed above the glumes; flowers perfect or the upper one 
staminate. Glumes unequal, the second the longer, shorter than the flowers, thin, rigid, 
obtuse. Lemma with a thickened 5-ribbed keel, wider than the glumes. Palet short, 
acute, the narrowly winged keels distant. Stamens 3. Grain black, with comb-like 
lines. W. E. (Ceres, the Greek goddess of the harvests, was worshipped in the 
town of Elusin.) E. indica Gaert. (Yard-grass) 
HORDEAE (BarRLeEy TrRIBE)—Leaf-blade with a more or less well-marked 

pair of auriculate appendages at the base. Inflorescence a spike, with | or more spikelets” 
at each joint of the rachis; rachis zigzaged, channeled. Spikelets sessile in the alternate 
notches of the rachis, I- to many-flowered. Glumes awnless or awned, or none. Up- 
per flowers of the spikelet imperfect. 
A. Spikelets solitary at each joint of the rachis. 
B. Spikes 4 mm. or less wide; spikelets 1 -flowered. SCRIBNERIA (p. 69) 
BB. Spikes 5 mm. or more wide; spikelets 3- to several-flowered. 
C. Spikelets placed with edge to the rachis; glumes |, or in the terminal spikelet 
Zs LoLium (p. 69)° 
CC. Spikelets placed with flat side to the rachis; glumes 2. 
D. Lemma with distinct callus at base, falling at maturity with the grain; 
grain adherent to the palet. AGROPYRON (p. 69) 
if 
