528 
42. CHLORIS Swartz. 
Spikelets with one perfect floret and oneor more rudimentary florets, 
imbricate-spiked in two rows on one side of a slender rachis: spikes 
digitate at the apex of the culm, erect or stellate spreading: empty 
glumes persistent, acute or mucronate, the second longer than the first, 
nearly equaling the floret: floral glume broad, deeply carinate, ciliate 
on the margin or intra-marginal nerves and usually on the keel, with a 
short dorsal awn near the apex or awnless; glumes of imperfect florets 
rolled in a broadly obovate or clavate cluster, the lowest glume in the 
cluster awned or awnless like the perfect floret.—Smooth flat-leaved 
annuals in low sandy land. 
* Awns longer than the spikelets, 
+ Floral glumes prominently pilose-ciliate. 
1. C. alba Pres]. Culms 4 to 8 dm. high, often branching, usually compressed: 
leaves acute, nearly smooth or thinly pubescent: spikes 6 to 15, ascending, 5 to 8 em. 
long: spikelets about 3 mm. long; awnsof tloral glume and rndiment4 to 8mm, long.— 
Wet land, western Texas to Arizona. 
+ + Floral glumes not conspicuously ciliate. 
2. C. verticillata Nutt. Culms 2 to5 dm. high, sometimes branching: leaves nar- 
row, abruptly acute: spikes 5 to 20 em. long, clustered at the apex of the culm or 
sometimes 2 or 3 verticillate clusters raised on a prolongation of the axis, usually 
pilose in the axils: spikelets 2 to 2.5 mm. long, rather loosely arranged along the 
rachis; awns 5 to 8mm. long.—Sandy land, central Texas to Oklahoma. Var. INTER- 
MEDIA Vasey, of the same range, has spikelets elose and awns shorter, the imperfect 
floret protruding. Intermediate between C. verticillata and €. cucullata. 
* * Awns shorter than the spikelets. 
+ Floral glumes nearly glabrous. 
3. C, cucullata Bisch. Culms 3 to5 dm. high, slender, rarely branched: spikes 8 
to 18, spreading, 3 to 5 em. long: spikelets triangular, 2 mm. long; hispid awns 
about one-half as long as the florets; imperfect floret very broadly obovate and 
protruding at the side of the spikelet.—Sandy land, central and southern Texas, 
+ + Floral glumes conspicuously ciliate. 
4. C. ciliata Swartz, var TRXaNa Vasey. Culms slender, 3 to 6dm. high, rarely 
branching: leaves subinvolute, attennate pointed: spikes 3 to 6, usually arcuate, 5 
to 8 em. long: spikelets about 2mm. long; awns slightly shorter than the tlorets.— 
Low land, southern Texas. 
* * Aunless. 
5. C. Swartziana Doell. Culms compressed, often branching, 4 to 8 din. high: 
leaves obtuse: spikes 2 to 5, nearly erect, 4 to 8 em. long: spikelets about 2 mm, 
long; floral glume usually brown, mucronulate.—Low sandy land, southern ‘Texas 
and Florida. 
43. TRICHLORIS Fourn. 
Spikelets with one perfect and one or more imperfect florets, sessile, 
spicate on one side of a narrow rachis: Spikes digitate or subdigitate 
