HITCHCOCK AND CHASE—GRASSES OF THE WEST INDIES. 279 
Spikelets awnless, 
Plants robust, 1.25 to 2 meters tall; spathes aggregated in 
a corymbose, usually dense inflorescence, 
19. A. bicornis. 
Plants slender, usually less than 1 meter tall; spathes not 
aggregated. 
Sessile spikelets about 3 mm. long; blades usually not 
over 2 mm. wide, the apex acuminate. 
20. A. leucostachyus. 
Sessile spikelets about 4 mm. long; blades 8 to 5 mm. 
wide, the apex boat-shaped___21. A. selloanus. 
Spikelets awned. 
airs of racemes few, terminal on the culms or the few 
simple branches, the common peduncle long-exserted. 
22. A. nashianus, 
Pairs of racemes several to many, subtended by well-devel- 
oped spathes. 
Blades involute; axis of raceme slender but straight 
23. A. urbanianus. 
Blades flat; axis of racemes delicate and flexuous. 
Racemes aggregated in a dense club-shaped or 
corymbose inflorescence, the ultimate 
spathes not over 2 mm. wide, rarely equal- 
ing their racemes______ 25. A. glomeratus. 
Racemes not aggregated, the ultimate spathes 3 to 
5 mm. wide, much exceeding their racemes. 
24. A. virginicus. 
1. Andropogon fastigiatus Swartz, Prodr. Veg. Ind. Occ. 26. 1788. 
Diectomis fastigiata H. B. K. Nov. Gen, & Sp. 1: 193. 1816. 
Sorghum fastigiatum Kuntze, Rev. Gen. Pl. 2: 791. 1891. 
A slender erect glabrous annual with flat linear blades and firm ligules up 
to 2 em, long; culms freely branching above, the racemes broad, with conspicu- 
ous sterile spikelets and geniculate awns about 4 cm. long. 
Dry open ground, southern Mexico and the West Indies to Brazil. Origin- 
ally described from Jamaica. 
Cuba, Jamaica, Haiti, Santo Domingo, Porto Rico, and Grenada. 
2. Andropogon brevifolius Swartz, Prodr. Veg. Ind. Occ. 26. 1788. 
Andropogon obtusifolius Poir. in Lam. Encycl. Suppl. 1: 583. 1810, 
Pollinia brevifolia Spreng. Pl. Pugill. 2: 13. 1815. 
Schizachyrium brevifolium Nees; Kunth, Enum. Pl. 1: 488. 1833. 
Sorghum brevifoliwm Kuntze, Rev. Gen. Pl. 2: 791. 1891. 
A slender trailing or reclining glabrous branching annual, with flat obtuse 
spreading blades and delicate racemes with small spikelets and awns about 8 
mm. long. 
Moist banks, tropical regions of both hemispheres. Originally described from 
Jamaica; A. obtusifolius described from Porto Rico. To be found in probably 
all of the West Indian islands from Cuba to Trinidad. Not represented in col- 
lections from the Bermudas and the Bahamas. 
8. Andropogon malacostachyus Presl, Rel. Haenk. 1: 337. 1830. 
Schizachyrium malacostachyum Nash, N. Amer, Fl. 17: 102, 1912. 
A slender erect glabrous branching annual up to 50 em. high, the flat near 
acute blades ascending, the numerous racemes erect, more or less fascicled, the 
geniculate awns about 12 mm. long. 
