55 
. flowering glumes oblong, obconie, 4 lines long, sparsely pubescent, constricted at the 
apex, the crown short-hairy, awn about 1 inch long, smooth, bent above.—Mexico 
(Pringle) and Arizona (Pringle, Lemmon, Tracy). Spikelets larger than in S. Bloomeri. 
Var. LEMMONI. Flowering glume brown, hairy, rather thicker than in the type, less 
tapering at the apex, and with a more decided constriction of the neck.—Mountains 
of Plumas County, Cal. (J. G. Lemmon). 
22, S. RichardsoniLink. (Gray’s Manual, 6th ed., p. 641.) Culm slender above, 
14 to 2 feet high, radical leaves slender, one-half to two-thirds as long as the culm; 
panicle loose and spreading, the branches in twos, the lower one 3 to 5 inches long, 
slender, nake¢. below, few-flowered near the apex; empty glumes unequal, the lower 
about 5 lines long, the upper one-fourth shorter, both 3-nerved ; flowering glumes 
3 lines long including the shor$ stipe, sparsely hairy, narrowed above, brown; awn 
10 to 12 lines long.—British Columbia, Montana to the Yellowstone Park. 
This is alarge form which Prof. Macoun calls var. major, and is larger, and perhaps 
specifically distinct from the ferm which is found on Lake Superior and eastward. 
23. S. Mongolica Turez. Act. Petrop. 1836, p. 42. Annual, culm slender, sim- 
ple, 10 to 15 liaes high; radical leaves filiform, erect, the lower 3 to 5 lines long, the 
cauline ones about 1 inch long; panicle 3 to 4 inches long, open, spreading, the lower 
branches in twos, filiform, 14 inches long, sparsely-flowered mostly above the middle, 
purplish; empty glumes equal, 24 lines long, obtuse, smooth; flowering glume 2 lines 
long, including the very short, obtuse callus, sparsely-hairy below, and at apex; awn 
plumose, twisted below, bent above, 6 to 8 lines long.—Mountains of Colorado. 
ORYZOPSIS Michx. 
This genus differs from Stipa in having a usually broader floral glume, 
the callus of which is shorter and blunt, and in having a very short and 
deciduous awn, which is sometimes slightly eccentric, or to one side. 
1. O. asperifolia Michx. (Gray's Manual, 6th ed., p. 642.) Culms 12 to 18 inches 
high, overtopped by the Jong and rigid persistent leaf from the base; the upper sheaths 
with very short or rudimentary blade; panicle linear, 2 to 3inches long, nearly simple, 
few-flowered; empty glumes 3 lines or more in length, the flowering glume as long, 
sparsely hairy, with a blunt hairy callus, awn 5or 6 lines long; palet about as long as 
. its glume and with 2 narrow lodicules nearly as long as the palet ; styles united 
below, slender.—New England to Minnesota and northward to Alaska; also Colo- 
rado to Texas. 
2. O. Canadensis Torr. (Gray’s Manual, 6th ed., p. 642.) Culms slender, 6 to 15 
inches high; leaves becoming involute, filiform, 6 to 10 inches long, or much reduced ; 
panicle narrow, 1 to 2 inches long; the branches usually in pairs, compound, erect ; 
spikelets less than 2 lines long; empty glumes broad, l-nerved; flowering glume, 
rather shorter, very pubescent, whitish; awn short (one-third to one-half line) and 
very deciduous, or wanting.— Maine to Colorado and northward. 
3. O. exigua Thurb. U. S. Exp. Wilkes, p. 481. Culms slender, tufted, 6 to 
15 inches high; leaves 4 to 5 inches, the upper 1 to 2 inches long, rigid, ligule con- 
spicuous, 1 line long; panicle 1 to 24 inches long, linear; the branches mostly simple, 
the lower sometimes in twos, erect and appressed ; empty glumes 2 to 2¢ lines long, 
the lower 1-nerved, the upper 3-nerved at base, obtuse and mucronate, pubescent, a 
little longer than the flowering glume, the latter sparsely pubescent; awn twisted 
below, about 2 lines long; palet equaling its glume; stamens 3, styles 3; lodicules 2, 
as long as the ovary.—Oregon and Washington. 
This species is closely allied to O. Canadensis, from which it differs in its more 
simple panicle, less pubescent flowering glume, and longer and less deciduous 
awns. 
4. O. Webberi Vasey. (Bot. Cal. 1. p. 283). Culms densely tufted, 4 to 7 inches 
high; leaves convolute, rigid, pungent, scabrous, the radical 3 to 4 inches long, the 
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