Part 3, 1915 J POACBAB 241 



numerous branches and branchlets and the long pedicels capillary; spikelets 1.2-1.3 mm. long, 

 about 0;5 mm. wide, ob ovate-elliptic, sparsely hirsute; first glume about half the length of the 

 spikelet, acute, 1 -nerved; second glume shorter than the sterile lemma, both 3-nerved, and at 

 maturity sometimes ruptured by the expanding fruit, often only the lower part of each re- 

 maining; fruit at maturity 1.3 mm. long, 0.6 mm. wide, elliptic, minutely papillose while im- 

 mature, becoming smooth but not polished. 



Type locality: Jamaica. 



Distribution: Mexico and the West Indies to Brazil and Ecuador. 



Illustrations: Field Columb. Mus. Publ. Bot. 3; 32 (as P. brevifolium) ; Contr. U. S. Nat. 

 Herb. 15: /. 125. 



This species has been referred to Panicum brevifolium L., of India. 



86. Panicum Urvilleanum Kunth, Rev. Gram. 403. 1831. 



Panicum megastachyum J. Presl, in Presl, Rel. Haenk. 1: 305. 1830. Not P. megastachyum Nees, 

 1826. 



Panicum Preslei Kunth, Enum. 1: 121. 1833. 



Panicum Urvilleanum longiglume Scribn. Bull. U. S. Dep. Agr. Agrost. 17: ed. 2. 49. 1901. 



Plants robust, erect from a creeping rootstock, 0.5-1 meter high; culms solitary or few in 

 a tuft, simple or branching at the base only, the nodes densely bearded, rarely visible; leaf- 

 sheaths overlapping, loose, densely, retrorsely, harshly villous; ligule densely ciliate, about 

 2 mm. long; blades 30-60 cm. long, 4^7 mm. wide, tapering from a flat base to a long involute- 

 setaceous point, retrorsely strigose to nearly glabrous on both surfaces; panicles short-exserted, 

 equaled or exceeded by the upper blades, 25-30 cm. long, about half as wide, rather many- 

 flowered, the glabrous to pilose, slender, flexuous branches ascending, producing spikelet- 

 bearing branchlets along the upper half to two thirds of their length; spikelets short-pediceled, 

 6-7 mm. long, about 2 mm. wide, and as much as 4 mm. thick, ovate, densely silvery- to tawny- 

 villous, strongly nerved but the nerves obscured by the pubescence; first glume clasping, two 

 thirds to nearly as long as the spikelet, sparsely villous or glabrescent toward the acuminate 

 apex; second glume slightly longer and more pointed than the sterile lemma, both exceeding 

 the fruit, the lemma inclosing a villous palea of equal length and a staminate flower; fruit 4.2-4.5 

 mm. long, about 1.6 mm. wide, the margins of the lemma clothed with long white hairs, other- 

 wise smooth and shining. 



Type; locality: Chile. 



Distribution: Southern Arizona and California; also in Chile and Argentina. 

 Illustrations: Kunth, Rev. Gram. pi. 115; Bull. U. S. Dep. Agr. Bot. 13 1 : pi. 2; 17: /. 

 345; Contr. U. S. Nat. Herb. 15: /. 127. 



87. Panicum parvifolium Lam. Tab. Encyc. 1: 173. 1791. 



Panicum brasiliense Spreng. Syst. 1: 321. 1825; 



Panicum ascendens Willd.; Spreng. Syst. 1: 321, as synonym. 1825. 



Panicum oplismenoides Nash, Bull. Torrey Club 30: 381 . 1903. Not P. oplismenoides Hack. 1888. 



Plants perennial, cespitose, decumbent or creeping, rooting at the lower nodes, glaucous 

 and glabrous throughout, or more or less pubescent; culms slender, branching, 20-80 cm. 

 long, leafy, with numerous short internodes, these and the nodes sometimes sparsely pilose; 

 leaf-sheaths rarely more than 1 cm. long, ciliate, and sometimes, especially on young shoots, 

 sparsely or even densely pilose; ligule nearly obsolete; blades 1-3 cm. long, 2-6 mm. wide, 

 oblong-lanceolate, rounded or subcordate at base, spreading or reflexed, or the upper and 

 often those of young shoots appressed, sometimes sparsely pilose at the base, or rarely pilose 

 on both surfaces; panicles short-exserted, 2-4 cm., rarely 6 cm. long, about as wide, loosely 

 flowered, the slender, flexuous branches spreading, the branchlets and pedicels divergent; 

 spikelets about 1.5 mm. long, 0.8 mm. wide, turgid, blunt, glabrous; first glume slightly more 

 than half the length of the spikelet, subacute, 3-nerved; second glume and sterile lemma sub- 

 equal, 5-nerved, the sterile palea nearly as long as its lemma; fruit 1.4 mm. long, 0.8 mm. wide, 

 ovate, smooth and shining. 



Type locality: Tropical America. 



Distribution: Costa Rica and the West Indies to Paraguay. 



Illustrations: Trin. Ic. pi. 236; Contr. U. S. Nat. Herb. 15: /. 130. 



Panicum brasiliense is a pubescent form with oblong -lanceolate moderately firm blades. 



Panicum cyanescens Nees (Agrost. Bras. 220. 1829), a South American species, has been 

 collected in British Honduras (see Contr. U. S.Nat. Herb. 17: 507. f. 93). It differs from P. 

 parvifolium by the less slender, more erect firm culms, longer blades (3-8 cm. long), and stiffly 

 ascending panicle-branches, naked below. 



