HITCHCOCK AND CHASE—GRASSES OF THE WEST INDIES. 347 
Bristles solitary, below only part of the spikelets; branches of the panicle 
elongate; blades broad, usually more than 1 cm. wide, plaited, tapering 
at each end. (Section PrycHopHyLLUM. ) 
Plants annual; blades 1 to 8 cm. wide; main panicle branches rather dis- 
tant, 1 to 3 em. long________________________________ 1. C. barbata. 
Plants perennial; blades 3 to 8 cm. wide; main panicle branches ap- 
proximate, mostly over 3 cm. long. 
Panicle dense, long and narrow, the branches ascending; sheaths gla- 
brous or mostly so ___ —_ _2. C. sulcata. 
Panicle loose, the branches spreadiug or drooping, the lower 10 to 15 
em. long; sheaths hirsute__.__....__._-_________ 3. C, palmifolia. 
Bristles 1. or more below each spikelet (or below only a part of the spikelets 
in C, setosa). 
Plants annual. 
Bristles antrorsely scabrous. 
Bristles 5 to 12 at the base of each spikelet; second glume half as 
long as the rugose fruit_____ 11. C. lutescens. 
Bristles 1 to 3 at the base of each spikelet; second glume about as 
long as the spikelet. 
Plants robust; spike 15 to 30 mm. thick; fruit smooth. 
12. C. magna. 
Plants slender, rarely 1 meter tall; spike scarcely 1 cm. thick; 
fruit slightly roughened_ 13. C. viridis. 
Bristles, or some of them, retrorsely scabrous. . 
Plants 1 meter or more tall; bristles mostly more than 1 cm. long, 
’ divaricate and implicate___._____________ 15. C. tenacissima. 
Plants low (rarely 70 cm. high), often spreading; bristles usually 
not over 5 mm. long, straight or nearly so. 
Rachis villous; bristles several below each spikelet. 
16. C. scandens. 
Rachis not villous; bristles 1 or 2 below each spikelet. 
14. C. verticillata. 
Plants perennial. 
Inflorescence a dense cylindrical spike. 
Nodes and sheaths glabrous____ _-9. C. geniculata. 
Nodes appressed-pubescent ; sheaths scibrous and sparsely hispid. 
10. C. hispida. 
Inflorescence more or less open or interrupted, or tapering, not a dense 
cylindrical spike. 
Blades commonly 8 em. wide, tapering into a long petiole-like base. 
8. C. vulpiseta. 
Blades mostly less than 2 cm. wide, not tapering into a petiole-like 
base. 
Spikelets at maturity globose, about as thick as long; bristles, 
or some of them, 2 cm. long or more. 
Sheaths densely long-villous on the collar; blades about 
2 em. wide____ - 7. C. impressa. 
Sheaths slightly pilose on the collar; blades about 1 cm. 
wide 6. C. onurus. 
Spikelets ovoid, longer than thick; bristles mostly less than 1 
cm. long. 
Blades slender, mostly less than 5 mm. broad; spike slen- 
der, very narrow_ 5. C. rariflora. 
