132 



CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Oplismenus thiebauti Fourn. Mex. PI. 2: 39. 1886. "Secus rivulum prope Acapulco 

 (Thiebaut n. 1074)." This specimen has not been examined. The description, 

 especially "spiculis remote binatis," and the locality indicate 0. rariflorus. 



DESCRIPTION. 



Culms sparingly branched, ascending from a decumbent base, as much as 50 cm. 

 tall but mostly less, glabrous or sometimes pubescent; sheaths glabrous or pubescent, 



densely ciliate on the margin, villous on the 

 collar; ligule a short ciliate membrane; blades 

 lanceolate or elliptic-lanceolate, mostly about 

 4 to 7 cm. long, rarely as much as 13 cm., 1 

 to 2 cm. wide, thin, glabrous, scabrous, or 

 sparsely pilose; panicle long-exserted, the 

 main axis 5 to 15 cm. long, scabrous; racemes 

 several, the lower distant, 2 to 5 cm. long or 

 even 7 cm., ascending, loosely flowered, the 

 rachis scabrous, often villous at base and pilose 

 at the insertion of the spikelets; spikelets 

 scattered, appressed to the rachis, the lower 

 pairs as much as 1 cm. apart; glumes more 

 than half as long as the sterile lemma, gla- 

 brous or hispidulous, rarely pilose, tapering 

 into a smooth awn, the first 3-nerved, the awn 

 3 to 8 mm. long, rarely longer, the second 5- 

 nerved, the awn very short or wanting; sterile 

 lemma 3 mm. long, mostly awnless; fruit 2.5 

 mm. long. 



This species is well distinguished by its long 

 loose racemes. 



DISTRIBUTION. 



Fig. 24. — Oplismenus rariflorus. From Hitch- 

 cock 9046, Guatemala. 



Moist shady places, Mexico and Guatemala; 

 Ecuador and Peru. 

 Sinaloa: Lodiego, Palmer 1656 in 1891. 

 Tepic: Tepic, Palmer 1931 in 1892. 

 Jalisco: Zapotlan, Hitchcock 7237. 

 Colima: Manzanillo, Palmer 1090 in 1890. 



Michoacan: La Correa, Langlasse 444. Morelia, Arsene in 1909. 

 Oaxaca: Pochutla, Liebmann 372. Keyes, Nelson 1772. Sierra de San Felipe, 



Pringle 4944. 

 Guatemala: Guatemala City, Hitchcock 9046. 

 Ecuador: El Recreo, Eggers 14897. 

 Peru: Mountains of Huanuco, Haenke (described as 0. loliaceus Beauv. by Presl). 1 



DOUBTFUL SPECIES. 



Oplismenus depauperatus Fourn. Mex. PI. 2: 38. 1886. "Orizaba (F. Mull. n. 

 2019 in meo herbario, Schafpn. n. 207 in herb. Franq.); in Cordillera Oajacensi (Gal. 

 n. 5847)." 



^el. Haenk. 1:320. 1830. 



