——— 
GRASS FAMILY. 
2. Aira praécox I. Early Hair-grass. (Fig. 
Aira praecox I,. Sp. Pl. 65. 1753. 
Glabrous and smooth throughout, culms 2/—4/ 
tall, erect, from an annual root, simple, rigid. 
Sheaths clothing the whole culm, the upper one 
often enclosing the base of the panicle; ligule about 
114’ long; leaves 1/ long or less, involute-setaceous; 
panicle contracted, strict, %s’-1’ in length; spike- 
lets about 112’’ long, the empty scales acute; the 
flowering scales acuminate, 2-toothed, about 114// 
long, bearing an awn 114’’-2’’ long. 
In dry fields, southern New Jersey and Pennsyl- 
vania to Virginia. Naturalized from Europe. May- 
july. 
42. DESCHAMPSIA Beauv. ASTLOSH Ol EELOW mej  LoL2. 
Perennial grasses with flat or involute leaves, and contracted or open panicles. Spikelets 
2-flowered, both flowers perfect, the hairy rachilla extended beyond the flowers or rarely 
terminated by a staminate one. Scales 4 (rarely more), the 2 lower empty, keeled, acute, 
membranous, shining, persistent; the flowering scales of about the same texture, deciduous, 
bearing a dorsal awn, the apex toothed. Palet narrow, 2-nerved. Stamens 3. Styles distinct. 
Stigmas plumose. Grain oblong, free, enclosed in the scale. [In honor of J. C. A. Loiseleur- 
Deslongchamps, 1774-1549, French physician and botanist. ] 
About 20 species, inhabiting cold and temperate regions, a few occurring in the high mountains 
of the tropics. Besides the following, some 6 others occur in the western parts of North America, 
Upper flowering scale reaching or extending beyond the apex of the empty ceales. 
Flowering scales about 1% "' long, erose-truncate; leaves flat. . D. caespitosa. 
Flowering scales about 2’’ long, acute or obtuse; leaves involute. zi D. flexuosa. 
Empty scales extending much beyond the upper flowering scale. 3. D. atropurpurea. 
2% Deschampsia caespitosa (I,.) Beauv. ‘Tufted Hair-grass. (Fig. 387.) 
Aira caespitosa Y,. Sp. Pl. 64. 1753. 
Be EE Se caespitosa Beauv. Agrost. 160. pl. 18. f. 3- 
Culms 2°-4° tall, erect, simple, smooth and gla- 
brous. Sheaths much shorter than the internodes; 
ligule 1//-3/’ long; leaves flat, 1/’-11%4/” wide, 
smooth beneath, strongly scabrous above, the basal 
ones numerous, one-quarter to one-half as long as 
the culm, those of the culm 2/-6/ long; panicle open, 
3/-9’ in length, the branches widely spreading or 
ascending, often somewhat flexuous, naked at the 
base, the lower 2’-5’ long; spikelets 134’/—2’’ long; 
flowering scales about 114’/ long, erose-truncate at 
the apex, the awns somewhat shorter or a little 
longer, the upper scale reaching to or extending 
beyond the apices of the empty ones. 
Newfoundland to Alaska, south to New Jersey, Illi- 
nois, Minnesota and in the Rocky Mountains and 
Sierra Nevada to New Mexico and California, mostly in 
wet soil. Alsoin Europe and Asia. July—Aug. 
