Graminaceae 53 
AVENA OATS 
Annual or perennial. Spikelets few-flowered, rarely |-flowered, in a loose panicle; 
rachilla jointed above the glumes, hairy under the lemma. Glumes’scarious at least at 
the apex, lanceolate, nearly equal. Lemma smaller than the glumes, rounded on the 
back, 5—1|-veined, 2-cleft at the apex, awned; awn dorsal, twisted; terminal lemma 
often smali, empty. Palet narrow, 2-toothed. Stamens 3. Grain pubescent or hairy, 
rarely smooth, deeply grooved, frequently adherent. (The Latin name. ) 
A. Lemma-awn 2—4 cm. long, abruptly bent near the middle, arising near middle of 
lemma. 
B. Lemma pubescent with long rigid brown hairs, also with ring ‘of stiff hairs at 
base. W. E. A. fatua L. (Wild Oats) 
BB. Lemma smooth except for ring of stiff hairs at base and for scabrous apex. 
W.-E. (A. fatua glabrescens.) 
A. fatua glabrata Pet. (Smooth Wild Oats) 
AA. Lemma-awn 2 cm. or less long, not or hardly abruptly bent, arising 34 way up 
lemma. 
C. Annual; spikelets 20—25 mm. long, 2—3-flowered; glumes 9—I |-veined. 
W. E. A. sativa L. (Cultivated Oats) 
CC. Perennial; spikelets 10—15 mm. long, 3—6-flowered; glumes 3—5-veined. 
E. A. striata Michx. (Perennial Oats) - 
FESTUCEAE (BLueE-Grass TRIBE)—Inflorescence a panicle, spike-like or 
spreading. Spikelets 2- to many-flowered, very rarely |-flowered; rachilla usually pro- 
duced above the upper floret or bearing | or more terminal lemmas. Glumes keeled, 
acuminate to obtuse, shorter than the first lmma. Lemma usually wider than the glumes, 
entire to 3-cleft, awnless, or with |—many awns (not ours); awns terminal, rarely dor- 
sal. Palet 2-keeled, usually as long as its lemma or nearly so. Stigmas plumose. Grain 
free from or adhering to the palet. 
A. Lemma with 1—3 veins. 
B. Rachilla with long hairs which exceed the lemma in length; plants tall, reed-like. 
PHRAGMITES (p.54) 
~ BB. Rachilla glabrous cr with short hairs which do not equal the lemma in length; 
plants not reed-like. 
C. Plant 1—2 dm. high; stems dichotomously branched; leaves crowded in 
dense tufts at the nodes or ends of the stems; stigma with short hairs on all 
sides. Munroa (p. 54) 
CC. Mest species taller; stems not dichotomously branched; leaves not in dense 
tufts along the stem; stigma plumose. 
ID. Glumes nearly equal in length, but very unlike in form, the first narrowly 
linear and |-veined, the second broadly obovate and obtuse and 3-veined. 
EATONIA (p. 55) 
DD. Glumes unequal in length, but similar in form. 
E. Lemmas acute or awned, the veins converging in the tip. 
KOELERIA (p. 55) 
EE. Lemmas obtuse, the veins parallel and not converging in the tip. 
F. Panicle narrow; spikelets 3—50-flowered; rachilla not jointed; lem- 
ma deciduous; palet persistent. ERAGROSTIS (p. 55) 
FF. Panicle open; spikelets 2-flowered; rachilla jomted; lemma and palet 
both deciduous. CATABROSA (p. 55) 
AA. Lemma with 5 or more veins. 
ge tel 
