124 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



KEY TO THE SPECIES. 



Awns antrorsely scabrous; plants annual 1 . O. burmanni 



Awns smooth or obscurely roughened; plants perennial. 

 Rachis of racemes mostly 2 to 3 mm. long, bearing usually not more than 5 spikelets; 



blades 1 to 3 cm. long, 4 to 10 mm. wide 2. O. setarius. 



Rachis of lower racemes more than 1 cm. long, bearing usually more than 8 spike- 

 lets; blades mostly more than 4 cm. long, 1 to 2 cm. wide. 



Racemes closely flowered, the lower 1 to 2 cm. long 3. O. hirtellus. 



Racemes loosely flowered, the lower 2 to 5 cm. long, the lower pairs of spikelets 

 as much as 1 cm. apart 4. O. rariflorus. 



1. Oplismenus burmanni (Retz.) Beau v. 



Panicum hirtellum Burm. Fl. Ind. 24. pi. 12. f. 1. 1768. Not Panicum hirtellum L. 

 1759. "Habitat in Indiis utrisque." The plate is rather crude but evidently repre- 

 sents the species now called Oplismenus burmanni. 



Panicum burmanni Retz. Obs. Bot. 3: 10. 1783. The name is based on Panicum 

 hirtellum Burm., but the species is briefly described and a specimen is said to have 

 been sent by Koenig. 



Panicum bromoides Lam. Tabl. Encycl. 1: 170. 1791. "Ex. ins. Franciae. Commers." 

 The type has not been examined, but the reference in the description to hirsute spikes 

 and short blades appears to identify the species with Oplismenus burmanni, to which 

 species the name is referred by most authors. 



Oplismenus africanus Beauv. Fl. Owar. 2: 15. 1809. The localities given with the 

 description are "Chama, Koto, Oware & Benin," on the coast of Guinea. The plate 

 identifies the species. 



Oplismenus bromoides Beauv. Ess. Agrost. 54. 1812. Presumably based on Panicum 

 bromoides Lam., though no direct reference to that species is given. Beauvois merely 

 says that Oplismenus includes "Panici spec. Lin., etc.," and makes several combi- 

 nations under Oplismenus, one of which is 0. bromoides. 



Oplismenus burmanni Beauv. Ess. Agrost. 54. 1812. Based on Panicum burmanni 

 Retz. 



Panicum album Poir. in Lam. Encycl. Suppl. 4: 274. 1816. "Cette plant croit a 

 File de Java. (V. S. in herb. Desfont.)." The type has not been examined, but the 

 description appears satisfactory for the reference of the name to Oplismenus burmanni. 



Panicum africanum Poir. in Lam. Encycl. Suppl. 4: 275. 1816. Based on Oplismenus 

 africanus Beauv. 



Oplismenus albus Roem. & Schult. Syst. Veg. 2: 890. 1817. Based on Panicum 

 album Poir. 



Orthopogon burmanni Trin. Fund. Agrost. 181. 1820. Based on Panicum burmanni 

 Retz . 



Oplismenus brasiliensis Raddi, Agrost. Bras. 40. 1823. "Invenitur in montanis 

 prope Tejucco, necnon in Monte nuncupate Corcovado.'" This is referred by Doell l 

 to Panicum compositum, but the description applies well to Oplismenus burmanni 

 {Panicum burmanni of Doell) . 



Oplismenus affinis Schult. Mant. 2: 273. 1824. "In St. Martha [Colombia]. 

 Bertero." The ample description applies well to Oplismenus burmanni. 



Panicum lappaceum Willd.; Spreng. Syst. Veg. 1: 306. 1825. Mentioned as a 

 synonym of Orthopogon burmanni. The type, collected by Humboldt in "America 

 merid.," has been examined in the Willdenow Herbarium at Berlin. 



Orthopogon africanus Sweet, Hort. Brit. 448. 1826. Based on Oplismenus africanus 

 "R. S." 



Oplismenus humboldtianus Nees, Agrost. Bras. 264. 1829. "Habitat in Brasilia 

 variis locis (Mart.)." Nees considers the Brazilian plant different from the East 

 Indian species and bases the name upon Oplismenus burmanni as described by 

 Humboldt, Bonpland, and Kunth. 



J Mart FL Bras. 2 2 : 146. 1877. 



