344 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Racemes villous with long hairs ; first glume awned from between 2 Lobes. 



1. 0. burmanni. 

 Racemes not villous or with a few long hairs only ; first glume tapering into the 

 awn. 

 Blades of flowering stems mostly 2 to 4 cm. long, 5 to 10 mm. wide ; racemes 

 short, usually 3 to 5 mm. long, containing 3 to 5 spikelets. 



2. 0. setarius. 



Blades of flowering stems mostly more than 4 cm. long ; racemes 1 to 3 cm. 



long _, 3. O. hirtellus. 



1. Oplismenus burmanni (Retz.) Beauv. Ess. Agrost. 54. 1812. 

 Panicum burmanni Retz. Obs. Bot. 3: 10. 1783. 

 Oplismenus cristatus Presl, Rel. Haenk. 1: 323. 1830. 



A low, creeping, freely branching annual with pilose sheaths, broadly lanceo- 

 late-elliptic blades, and 3 to 5 pale villous ascending racemes approximate along 

 a flexuous axis ; awns slender, about 1 cm. long. 



Open or somewhat shaded ground and waste places, Mexico to South 

 America; also in Santo Domingo (Maniel de Ocoa, Constanza). Common in the 

 Tropics of the Old World, whence probably introduced into America. Origi- 

 nally described from India. Oplismenus cristatus was described from Mexico. 



2. Oplismenus setarius (Lam.) Roem. & Schult. Syst. Veg. 2: 481. 1817. 

 Panicum setarium Lam. Tabl. Encycl. 1: 170. 1791. 



Orthopogon setarius Spreng. Syst. Veg. 1 : 30G. 1825. 



A slender creeping branching perennial, the ascending flowering stems 20 

 to 30 cm. high, the small lanceolate blades conspicuously undulate-margined, 

 the rachis of the distant racemes very short, the spikelets appearing to be in 

 clusters on the rather strict axis. 



Moist woods and shady banks, Georgia to Texas and in the West Indies, 

 here common in the coffee groves. Originally described from tropical America, 

 the particular locality not given. 



Bermuda, Bahamas, Cuba, Jamaica, Santo Domingo, Porto Rico, St. Thomas, 

 St. Croix, St. Kitts, Antigua, Dominica, Martinique, and Trinidad. 



3. Oplismenus hirtellus (L.) Beauv. Ess. Agrost. 54, 168. 1812. 

 . , / Panicum hirtellum L. Syst. Nat. ed. 10. 2: 870. 1759. 



4 ' / Orthopogon hirtellus Nutt. Gen. PI. 55. 1817. — 4-* 



{Orthopogon loliaceus Spreng. Syst. Veg. 1: 306. 1825?) - - -— .— -7— 

 aX* Orthopogon cubensis Spreng. Syst. Veg. 1: 307. 1825. 



Oplismenus cubensis Kunth, Rev. Gram. 1: 45. 1829. 



Panicum cubense Steud. Nom. Bot. ed. 2. 2: 255. 1841. 



Mostly less slender than the preceding, taller, the blades longer, the ascending 

 or spreading racemes sometimes 3 cm. long. This species is exceedingly 

 variable in size, pubescence, length of racemes, and length of awns, and ap- 

 parently intergrades with O. setarius. The sheaths vary from glabrous to 

 conspicuously hirsute. Grisebach 1 refers the form with glabrous sheaths to 

 Orthopogon loliaceous Spreng. {Oplismenus loliaceus (Lam.) Beauv.), an 

 Asiatic species. A variegated form has sometimes escaped from cultivation 

 (Guadeloupe, Duss 3155. Martinique, Duss 1325. Dominica, Jones 37). 



Moist woods and shady banks, Mexico and throughout the West Indies to 

 South America. The type specimen was from Jamaica. Orthopogon cubensis 

 was described from Cuba. Richard 2 refers the pubescent form to O. undula- 

 iifolvus Roem. & Schult. In Cuba called " pitillo." 



*F1. Brit. W. Ind. 545. 1864. a In Sagra, Hist. Cuba 11: 308. 1850. 



