Part 3, 1915] POACEAE 



237 



the upper shorter than the internodes; ligule fimbriate, scarcely 0.5 mm. long; blades 5-15 

 cm. long, 2-4 mm. wide, at the base scarcely as wide as the sheaths, erect or ascending, folded 

 and more or less twisted, glabrous or with a few long hairs on the upper surface at the base; 

 panicles very long-exserted, 3-11 cm. long, dark-purple, composed of a few distant, slender, 

 appressed or ascending branches, naked about half their length, bearing short, crowded branch- 

 lets with densely clustered spikelets along the upper half or toward the ends; spikelets 3 mm. 

 long, about 1.2 mm. wide, and at maturity nearly twice as thick, rather strongly nerved; first 

 glume one third the length of the spikelet or less, obtuse, concave along the midnerve ; second 

 glume and sterile lemma equal, exceeded by the enlarged sterile palea, the lemma strongly 

 concave along the midnerve below; fruit 2.4 mm. long, 0.8 mm. wide, the margins of the lemm? 

 more inrolled than in P. hians, the apex tipped with a minute bit of hyaline membrane. 



Type locality: Flor de Maria, State of Mexico. 



Distribution: Southern Mexico. 



Illustration: Contr. U. S. Nat. Herb. 15: /. 113. 



74. Panicum stolonif erum Poir. in Lam. Encyc. Suppl. 4: 274. 1816. 



Panicum ctenodes Trin. Ic. pi. 171. 1829. 

 Panicum Leprieurii Steud. Syn. Gram. 65. 1854. 



Plants creeping, freely branching; culms 10-50 cm. long, with two opposite lines of minute 

 crisp pubescence, rarely pubescent all over or glabrate, the nodes pubescent or glabrous; leaf- 

 sheaths shorter than the internodes or overlapping on the branches, ciliate, otherwise glabrate, 

 or crisp-pubescent; ligule fimbriate, about 0.2 mm. long; blades 1-5 cm. long, 3-15 mm. wide, 

 the margins undulate, glabrous or sparsely pilose on the upper surface, minutely soft-pubescent 

 beneath; panicles 1-5 cm. long, about one third as wide; racemes 5-10 mm. long, ascending or 

 spreading, the main axis more or less pubescent; spikelets 2.3-2.5 mm. long, about 0.6 mm. 

 wide and 1 mm. thick, glabrous ; first glume about one third the length of the spikelet, 3-nerved, 

 blunt; second glume blunt, shorter than the acute sterile lemma, both somewhat boat-shaped, 

 5-nerved, the sterile palea about half as long as its lemma; fruit 1.3 mm. long, 0.5 mm. wide, 

 acute. 



Type locality: Cayenne. 



Distribution : Guatemala to Brazil and Ecuador. 



Illustrations: Kunth, Rev. Gram. pi. 22 ; Trin. Ic. pi. 171 ; Contr. U. S. Nat. Herb. 15 : /. 114. 



75. Panicum frondescens G. Meyer, Fl. Esseq. 56. 1818. 



Panicum olyraefolium Raddi, Agrost. Bras. 43. 1823. 



Panicum ctenodes majus Trin. Ic. pi. 171, f. A. 1829. 



Panicum stolonif erum majus Kunth, Rev. Gram. 389. 1831. 



Panicum brachyclados Reichenb.; Trin. M6m. Acad. St.-Petersb. VI. 3«: 25!, as synonym. 1834. 



Panicum Kegelii Steud. Syn. Gram. 65. 1854. 



Panicum umbrosum Salzm.; Steud. Syn. Gram. 65, as synonym. 1854. 



Hymenachne frondescens Fourn. Mex. PL Gram. 36. 1886. 



Culms ascending from a decumbent or creeping base, less freely branching than in P. 

 stolonif erum, 30-50 cm. high, compressed, glabrous except below the panicle or sometimes with 

 two lines of pubescence toward the summit of the internodes ; nodes black ; leaf -sheaths shorter 

 than the internodes, densely ciliate, otherwise glabrous; ligule nearly obsolete; blades 5-1 1 cm. 

 long, 12-20 mm. wide, acuminate, narrowed toward the base, glabrous; panicles 5-11 cm. long, 

 usually less than one third as wide, rather compact, the numerous, approximate racemes as- 

 cending or somewhat spreading, the lower 10-25 mm. long; spikelets 2.6-2.8 mm. long, about 

 0.6 mm. wide and 1 mm. thick, glabrous; first glume scarcely one third the length of the spikelet, 

 acute, scabrous on'the midnerve; second glume and sterile lemma subequal, somewhat boat- 

 shaped, acute, the sterile palea about two thirds as long as its lemma; fruit 1.6 mm; long, 0.5 

 mm. wide, pointed, short-stipitate. 



Type locality : Island of Arouabisch, British Guiana. 



Distribution: Southern Mexico to Brazil l1 *»* x a ^ *tto*t*ttw 



Illustrations: Raddi, Agrost. Bras. pi. l,f.6\ Trin. Ic. pi. 171, f. A ; Contr. U. S. Nat. Herb. 



15: f. 115. 



76. Panicum pulchellum Raddi, Agrost. Bras. 42. 1823. 



Eriochloa ? pulchella Kunth, Rev. Gram. 30. 1829. 



Panicum leptostachyum J. Presl, in Presl, Rel. Haenk. 1:J11. 1»^U. 



Hymenachne leptoslachya Fourn. Mex. PL Gram. 36. 188o. 



