A497 
§3. Racemes panicled at the summit of the usually simple culm; rachis joints and pedicels 
with a median longitudinal translucent line: floral glume pedicel-like, tapering into the 
awn,—AMPHILOPHIS, 
11. A. Wrightii Hack. Culms 5 to 10 dm. high, simple, slender: racemes 3 to 7, 
subfastigiate or apparently digitate, 5 to 8cm. long, of 10 to 15 joints; peduncles 
glabrous, 5 to 15 mm, long; rachis joints and pedicels ciliate: sessile spikelets about 
5mm. long; first glume 7-nerved, ciliate on the margins and often hairy near the 
base, usually with a punctate depression in the median line; awn 1.5 em. long: ped- 
icellate spikelet staminate or neutral, with 3 or 4 glumes as long as the sessile one.— 
Rare, western Texas. 
12. A. saccharoides Sw. Culms5 to 10dm. high, erect or ascending, often branch- 
ing below, usually barbellate at the nodes: racemes 15 to 30 in erect close panicles 
about 1 dm. long, the upper racemes usually single and sessile, the lower ones in twos 
or threes, on short, branching, glabrous peduncles; rachis joints and pedicels densely 
villous, with white hairs longer than the spikelets: sessile spikelet 5 to 6 mm. long; 
first empty glume 7 to 9-nerved, hispid-ciliate on the keels and slightly pubescent 
on the flat back; awn usually golden, 2 em, long.—Along water courses, Mississippi 
toSouthernCalifornia, Var.GLaucus(Torr.) Scribn. has leaves and sheaths generally 
smooth and glaucous, nodes barbellate, and spikelets 4 to 5 mm. long. (4. sacehar- 
oides var. Torreyamis Hack.)—On hillsides in drier localities than the species. Var. 
suBMUTICUS Vasey has a narrow and rather dense panicle, and small spikelets 3 
to4 mm, long, short-awned or awnless. Var, PERFORATUS Hack. has a corymbose 
panicle, 2 to 7 racemes, and first elume with a punctate depression on the back.— 
Central Texas to Northern Mexico. 
12. HILARIA HBK. 
Inflorescence in solitary terminal spikes: spikelets in clusters of 3, 
closely sessile at the nodes of the rachis; the central spikelet contain- 
ing a single pistillate or perfect floret; the lateral spikelets each with 
two or three staminate florets; outer glumes of the spikelets unlike, 
mostly thin with strong, rigid nerves, usually obliquely lobed, and 
awned on the side or back or between the lobes; outer glumes of the 
lateral spikelets standing in front of the cluster like an involucre; those 
of the central spikelet more slender, standing between the cluster and 
the rachis; floral glume mucronate or with a very short awn just 
below the apex: the cluster of spikelets falling entire at maturity: 
hardy perennials.—Said to be very nutritious and valuable for grazing, 
on the high plains. 
1. H. cenchroides HBK., var. TEXANA Vasey. Multiplying by suckers at inter- 
vals of 1 to 2 dm.: culms slender, 2 to 3 dm. high, barbellate at the nodes: leaves 
narrow, rigid, 5 to 10 em. long, thinly pubescent: spikes 3 to 4 cm. long, rather 
loosely flowered with 5 to 10 clusters of spikelets, often purple; hairs at the base 
about 1mm. long: spikelets 4 to 6 mm. long; empty glumes scabrid, cleft into 2 
linear unequal lobes, entire or merely erose with awns about equaling the spikelets.— 
Dry. hills and high prairies, Central Texas to Arizona and Mexico. 
2. H. mutica (Buckl.) Benth. Rootstocks creeping, strongly rooted: culms 3 to5 
dm. high, in small tufts or sometimes bunched: leaves usually hispid, flat or involute 
toward the sharp points: spikes 6 to 8 em. long, densely flowered, usually white: 
spikelets 6 to7 mm. long; hairs at the base about 2 mm. long; glumes all thin at the 
apex, ciliate or fimbriate; outer ones of the central spikelet with 5 or 6 awns shorter 
than the floret; outer ones of the lateral spikelets narrowly cuneate, equaling the 
