AIRA. 
38 r> 
21. Aik A Limi. 
* Outer pale truncate, Nut free, not furrowed on the back. 
t Awn straight. Deschampsia lieauv. 
1. A. caspitosa (L.); panicle s])rea(ling, l.tlat, glumes slujhthj 
rough at the midrib, awn from below the middle of the pale and 
scarcely extending heyond its snnnnit.— JJ. B. 1453. R. I(i82 — 
Ki8(). P. 23. — Root tufted. St. 1 — 3 feet high. L. rigid, rongh- 
ish, their margins involute when dry. Branches of the panicle 
rough. Outer pale with 4 nerves in addition to that which ter- 
minates in the rongh awn. Rudiment of the third H. often 
scarcely, if at all, distingnishahle, or, in other cases, half the 
length of the upper tl. and somewhat clavate. — brevifolia{Par.); 
radical 1. short, sheaths and st. smooth, panicle small. P. lOd. 
Oftentfiken for A. — Meadows, thickets, &c. /3. Mountain 
tops. P. VII. 
tt Awn bent, twisted at the base. 
2. A. alpina (L.) ; panicle close, 1. mostly involute, glumes 
smooth on midrib, awn from above the middle of the pale and 
scarcely extending beyond its summit. — E. B. 2102. P. 23. — 
Height () — 12 in. L. narrow, rigid, roughish on the upper sur- 
face. Branches of the panicle quite or nearly smooth, lower ones 
lax, upper erect. FI. often viviparous. — Tops of highland moun- 
tains. P. VIII. S. 
3. A.flexuosa (L.); panicle spreading triply forked with wavy 
branches, 1. very narrow subsetaceous, awn from near the base of 
the pale and extending considerably beyond its summit, ])edicel 
of the second tl. less than ^ of its length, ligule truncate. — E. B. 
151.9. R. 1(1/8 — 1(179. P. 107- — St. erect, slender, about a foot 
high. L. solid, nearly terete. Upper sheaths rough from above 
downwards. Outer pale notched at the summit. — Heathy places. 
P.VII. 
** Outer pale bifid. Nut adnate to the pales, ‘'furrowed on 
the back.” Airop.sis Fries. 
4. A. canjophyllea{lj.); panicle spreading trijdy forked, glumes 
rounded at the base, awn from below the middle of the pale and 
extending considerably beyond its attenuated deeply bifid point. 
— E.B. 812. P. 167(1. P.24. Avena Koch. — St. (1 — 12 in. high. 
L. short and narrow. Sheaths roughish from beloio uptoards. 
Spikelets very small, rounded below, chiefly collected at the ends 
of the branches ; no riubment of a third floret. — Dry gravelly 
places. A. VI. 
5. A. jiracox [h.) •, panicle spikelike oblong, glumes scarcely 
rounded at the base, awn from below the middle usually near the 
base of the pale and extending considerably beyond its attenuated 
