HITCHCOCK AND CHASE—NORTH AMERICAN PANICUM. 77 
upper blades, 20 to 30 cm. long, usually less than half as wide, the branches ascending, 
naked at the base, the branchlets more or less appressed, bearing short-pediceled, 
approximate, but not crowded spikelets 3 mm, long, 1 mm. wide; first glume half to 
two-thirds the length of the spikelet, acute, 3 to 5-nerved; second glume and sterile 
lemma strongly 7 to 9-nerved; fruit 1.9 to 2 mm. long, 0.9 mm. wide, elliptic. 
This species differs from P. diffusum in its robust habit, wider, flat blades, hirsute 
on both surfaces, and in its larger spikelets. 
DISTRIBUTION, 
Low moist ground, Mexico, Central America, and the West Indies; also in Ecuador, 
Mexico: Borrego prés Orizaba, Bourgeau 2751; Yucatan, Izamal, Gawmer 2477. 
Costa Rica: Salinas Bay, Pittier & Durand 2633. 
CuBa: Santiago de las Vegas, Tracy 9116; Herradura, Tracy 9068; La Soledad, 
Eggers 5406; Calvario, Leén 922; Guayabal, Leén 922b; without locality, 
Wright 758. 
Porto Rico: Tabucoa, Sintents 4983. 
LEEWARD IsLANbDs: Guadeloupe, Duss 3184 and a specimen without number or 
date. 
Ecuapor: Manabi, Lggers 15419. 
38. Panicum hirsutum Swartz. 
Panicum hirsutum Swartz, Fl. Ind. Occ. 1: 173. 1797. ‘‘Habitat in Jamaicae et 
Hispaniolae graminosis.’’ The type, in the Swartz Herbarium, is from ‘Jamaica, 
Swartz.”’ 
DESCRIPTION. 
Plants robust, culms as much as 1 cm. thick and 1.5 meters or more high, simple or 
sparingly branching, glabrous or with a few scattered hairs, the nodes appressed- 
pubescent; sheaths mostly overlapping, appressed papil- 
lose hirsute, the hairs sometimes dense at the summit; 
ligules dense, about 3 mm. long; blades flat, 20 to 50 cm. 
long, 20 to 35 mm. wide, scarcely narrowed to the rounded 
base, glabrous or with a few hairs toward the base, the 
margin serrulate; panicles short-exserted or included at 
base, 20 to 35 cm. long, 3 to 12 mm. wide, compact, 
densely flowered, the long lower branches erect, naked 
at base; spikelets 2 to 2.2 mm. long, about 0.9 mm. wide, 
rather turgid, abruptly pointed; first glume scarcely half — Fic. 66.—P, hirsutum. From 
the length of the spikelet, acute, 3 to 5-nerved; second type Specimen. 
glume and sterile lemma 5 to 7-nerved; fruit 1.5 mm. long, 0.7 mm, wide, elliptic. 
This species is much more robust than any other in this group, to which, because 
of its compact panicle, it is not very closely allied. 
& 
DISTRIBUTION. 
Gravelly river banks and wet places, Mexico, Central America, and the West Indies. 
LEEWARD IstaNps: Guadeloupe, Duss 3917. 
Mexico: Oaxaca, Pringle 5578. 
Costa Rica: Confluence of Puerto Viejo and Sarapiquf, Biolley 7467; Port Limon, 
Pittier in 1904. 
Trinipap: Botanic Gardens Herb. 2295, Broadway 2629. 
