59 
empty glumes about equaling the flowering glume, barely pointed ; flowering glume 
oblong, obtuse, or apiculate, 3-nerved, smooth; palet equaling the glume.—Texas to 
Arizona ard Mexico. 
ARCTAGROSTIS Griseb. 
Spikelets one-flowered, in a contracted, mostly spike-like panicle; 
pedicels of the spikelets rather clavate and usually articulated below 
the glumes; outer glumes nearly equal and long-awned from the apex ; 
flowering glume smaller, thinner, generally hyaline, and generally pro- 
longed at the apex into a slender awn; palet thin, sometimes consider- 
ably shorter than its glume. 
1. Arctagrostis latifolia Griseb, Flora Rossica Iv. p. 434. (Colpodium latifo- 
lium R.Br.) Culms strict, smooth, 6 to 12 inches high; leaves broadly linear; ligule 
short-oblong, truncate, lacerate; panicle lanceolate-linear, contracted ; spikelets large; 
empty glumes ovate-oblong, acutish, the upper one-third longer than the lower; flow-_ 
ering glume3 herbaceo-membranaceous, sparsely scabrous-pubescent, about 2 lines 
long, t to $ longer than the upper glume, obscurely 3-nerved; palet nearly equal to 
its glume.—Point Arrow, Fort Conger and Arctic coast. . 
Var. ARUNDINACEA Griseb, in Flora Rossica (var. Alaskensis Vasey; Sporobolus 
arundinaceus Vasey; Vilfa arundinacea Trin, Icones Gramin. 1. pl. 55). Culms taller 
(2 to 3 feet), panicle laxer and larger, floral glume obscurely 5-nerved.—Alaska. 
SPOROBOLUS R. Br. 
Spikelets 1, or rarely 2-flowered, in a contracted or open panicle. 
Outer glumes unequal, the lower one shorter, often acute, unawned, 1- 
to 3-nerved, membranaceous ; flowering glume mostly longer, unawned ; 
palet about equaling the flowering glume, and of the same texture, 
prominently 2-nerved. Seed mostly loose in a hyaline or rarely coria- 
ceous pericarp. 
§ 1. Panicle contracted, spike-like, or becoming somewhat spreading. Culms erect or 
spreading, scarcely branched, 
1. Sporobolus Indicus Rk. Br. (Gray’s Manual, 6th ed., p. 646.) Culms tufted, 
erect, l to 3 feet high, smooth, lower leaves halfas long as the culm, terminating in 
a long, fine point; the upper similar; ligule obsolete; panicle narrow, 4 to 12 inches 
long, tapering at the point, often interrupted at the base ; branches one-half to 14 
inches long, erect, flowering to the base ; spikelets sessile, crowded on the branches, 
about 1 jine long; empty glumes obtuse, the lower one-half, the upper two-thirds as 
long as the floral glume; floral glume acutish, 1-nerved; palet about as long as its 
glume, faintly 2-nerved.—Introduced, but widely dispersed. 
2. S. Virginicus Kth. (Gray’s Manual, 6th ed., p. 646.) (Vilfa Virginica Beauv. ; 
Podosemum Virginicum Link.) Culms much branched at base, from a running root- 
stock, erect or decumbent 6 to 12 inches high; leaves short and convolute, distich- 
ous, rigid, often spreading and recurved ; panicle 2 to 4 inches long, densely flowered, 
or sometimes lax ; spikelets about 14 lines long, the empty glumes nearly erect, peren- 
nial.—Seacozest, Virginia to Florida and Texas. 
3. S. asper Kth. (Gray’s Manuai, 6th ed., p. 645). (Vilfa Hookeri Trin.; Agrostis 
longifolia Torr.) Culms tufted, 2 to3 feet high, rather stout; lower leaves 1 foot long, 
tapering to an involute point, the culm leaves shorter than the internodes, the upper 
one inflated, partly or wholly inclosing the 4 to 6 inch long panicle; spikelet 2 to 24 
lines long, ernpty glumes broad, obtuse, the lower one-half and the upper two-thirds 
as long as the spikelet, flowering glume and palet nearly equal, smooth or pubescent 
below, obtusish at apex.—Maine to Texas, 
