amen 
TRIANDRIA, DIGYNIA. ~ sr 
gid, often setiform, mucronate or diminishing into a mere 
awn. xteror valve of the corolla generally awned. 
Species. 1. E. philadelphicus? 2. canadensis, These 
ih 2 are probably the same species. 3. glaucifolius. A very 
imperfectly defined species, and very nearly allied to 
No. 2. 4. villosus. 5. virginicus. 6. striatus. 7. europeus. 
—§1r. AsPERELLA. Calix 0. Corolla 2-valved. Exterior 
valve larger, mucronate—Humboldt. 9. Hystrix? Spike- 
lets 4-flowered; involucrate ealix 0, but corresponding 
Callosities in its place. : 
_A genus of but few species, existing in Europe, Ame- 
rica, Northern Asia (Siberia), and Northern Africa (Bar- 
bary). Except in North America, where 8 out of 11 spe- 
Cies exist, this genus is confined to the sea-coast. The 
£. arenarius, is: one of those grasses which assist in a¥- 
resting the progress of moveable sands. 
119. HORDEUM, L. (Barley.) 
_ Calyces lateral, 2-valved, mostly 1-flowered, 
‘ aggregated by threes, so as to resembie a seta- | 
ceous 6-leaved involaucram; the central flower 
Sessile, the lateral ones stipitate, usually sterile. | 
Corolla 2-valved, acute; exterior valve awned, 
Very nearly allied both by habit and character to the 
preceding genus. Fiowers spiked, imbricated mostly in 
2 rows; calycine involucrum setaceous, 6-leaved, divisions _— 
Bas approaching by pairs. In the . hexastichon, the flowers — 
& -are imbricated im 6 ranks, because all the flowers are 
hermaphrodite; probably a mere effect of cultivation. 
Species. 1. # vulgare. Cultivated. Flowers all her- | 
maphrodite; probably the effect of culture? Still found — 
, wild about Margamen in Sicily. 2. *pusiilum. Lateral - 
masculine or neutral flowers awnless, acute; four internal 
calicine glumes, coriaceous and dilated, those of the her- _ 
| maphrodite sublanceolate; internal valve of the lateral _ 
e Masculine flower, subsemi-ovate. : ioe 
Culm 4 to 6 inches, decumbent, or somewhat geniculat 
at the base. Leaves rather glaucous, a little pubescent on 
the under surface, siriate, about one and a half inches 
long, and almost obtuse; uppermost sheath tumid and _ 
very smooth, embracing the spike. Spike linear; about 
oe 
1384 
: one and a half inches long. Glumes by threes, dis- 
~ tichelly imbricated. Lateral imperfect flowers awnless, 
“acute; centralsessile flower awned, the awn almost ex. 
actly the length of that of the subtending 
