Part 2, 1912] POACEAE © 129 
Stems 1 m. tall or more, glabrous, with the exception of the usually barbed nodes; leaf- 
sheaths glabrous, rarely hirsute at the apex; blades up to 5 dm. long and 7 mm. wide, involute 
or flat, glabrous; panicle 1-2 dm. long, oblong to oblong-linear; spikelets 3.5-5 mm. long, 
usually yellowish-brown, hirsute, the awn imperfect, 1-3 mm. long, or perfect, the exserted 
portion not longer than the spikelet. 
TYPE LOCALITY: Cuba. 
DISTRIBUTION: Continental tropical America, Jamaica, Cuba, and Haiti. 
2. Sorghastrum nudipes Nash, sp. nov. 
A slender tufted grass, with short extravaginal innovations, the leaf-blades of which are 
3-6 cm. long. Stems 6—8 dm. tall, smooth and glabrous; leaf-sheaths smooth and glabrous; 
blades erect, up to 1.5 dm. long, 3-5 mm. wide, flat, glabrous, usually rough; panicle 8-12 
em. long, loose and open, broad, the capillary branches and their divisions naked below the 
middle, the few spikelets borne at their ends; spikelets 6-7 mm. long, hirsute, the perfect 
awn 1-1.5 cm. long, the straight, or sometimes geniculate, column much exserted. 
Type collected on pine plains, base of the Sierra Madre, Chihuahua, Mexico, September 
18, 1887, C. G. Pringle 1433 (herb. Columbia Univ.). 
DISTRIBUTION : Chihuahua. ‘ 
3. Sorghastrum stipoides (H.B.K.) Nash. 
Andropogon stipoides H.B.K. Nov. Gen. & Sp. 1: 189. 1816. 
?Sorgum parvifiorum Desv.; Hamilt. Prodr. 12. 1825. 
Andropogon Humboldtianus Steud. Syn. Gram. 392, 1854. 
? Andropogon rufidulus Steud. Syn. Gram. 392. 1854. 
Sorgum nutans avenaceum stipotdes Hack, in Mart. FI. Bras. 23: 274, 1883. 
Andropogon nutans stipoides Hack. in DC. Monog. Phan, 6: 530. 1889. 
Stems up to 1.5 m. tall; leaf-sheaths smooth and glabrous; blades up to 4 dm. long, 
2-5 mm. wide, usually convolute, rarely flat, glabrous or pubescent; panicle 1-3 dm. long, 
usually loose and open, rarely contracted; spikelets about 5 mm. long, hirsute, the awn of the 
fourth scale 1-1.5 cm. long, the straight, very rarely geniculate, column commonly much 
exserted. 
TYPE LOCALITY: Between Popayan and Almaguer, near Rio Putes, at the foot of Mt. Socobon, 
Colombia. 
DISTRIBUTION: Cuba; Mexico; also in northern South America. 
4, Sorghastrum nutans (J,.) Nash, in Small, FI. 
SE. U.S. 66. 1903. 
Andropogon nutans I,. Sp. Pl. 1045. 1753. 
? Stipa villosa Walt. Fl. Car. 78. 1788. 
Andropogon avenaceus Michx. Fl. Bor. Am. 1: 58. 1803. 
Andropogon ctliatus Ell. Bot. S. C. & Ga. 1: 144. 1816. 
Sorgum nutans A, Gray, Man. 617. 1848. 
Sorgum avenaceum Chapm. Fl. S. U. S. 583. 1860. 
Andropogon confertus Trin.; Fourn. Mex. Pl. Gram. 55. 1881. 
? Andropogon albescens Fourn. Mex. Pl. Gram. 56. 1881. 
Chrysopogon nutans Benth.; Vasey, Grasses U.S. 20. 1883. 
Chrysopogon avenaceus Benth.; Vasey, Grasses U. S. 20. 1883. 
Andropogon nutans avenaceus Hack, in DC. Monog. Phan. 6: 530. 1889. 
Sorghasirum avenaceum Nash, in Britton, Man. 71. 1901. 
Stems 1-2.5 m. tall; leaf-sheaths usually smooth and glabrous, or the lowermost ones 
sometimes pubescent; blades 6 dm. long or less, up to 15 mm. wide, rough; panicle 2-5 
dm. long, loose, the apex usually nodding, its branches erect or nearly so, at least the lower 
ones much exceeding the internodes of the axis, 7-10 cm. long, the ultimate divisions straight; 
spikelets 6-8 mm. long, lanceolate, golden-brown at maturity, hirsute, the awn of the fourth 
scale geniculate, 1-1.5 em. long, the column straight, usually not or but little exserted. 
TYPE LOCALITY: Virginia. 
DISTRIBUTION: Rhode Island to Ontario, Manitoba, and South Dakota, and southward to 
Florida, Arizona, and northern Mexico ; also in South America. 
ILLUSTRATIONS: Vasey, Agr. Grasses U. S. pl. 28; ed. 2. pl. 30; Bull. U.S. Dep. Agr. Agrost. 
7: f. 15, Bull. Tenn. Exp. Sta. 5: f.4; 7: 61. 3, f. 12; Britt. & Brown, Ill. Fl. f. 224; Bull. U. S. 
Dep. Agr. Bot. 1: p//7; 6: pl.9; Rep. Sec. Agr. 1892: Bot. pl. 4; Cire. U. S. Dep. Agr. Agrost. 
4: f.4. 
