HITCHCOCK AND CHASE — NORTH AMERICAN PANICUM. 



23 



J 



First glume acute/ second glume about two-thirds as 

 long as fruit. 



Spikelets 1.5 mm. long; blades involute 1. P. distantiflorum. 



Spikelets 2 mm. long; blades scarcely involute . . 2. P. utowanaeum. 

 Blades usually less than 10 cm. long, not narrowed toward the 

 base; spikelets 2.5 to 3 mm. long. 

 Blades of mid-culm long-acuminate, usually 2 to 3 mm. 



wide 4. P. ramisetum. 



Blades of mid-culm abruptly acute, usually 4 to 6 mm. 



wide 6. P. firmulum. 



1. Panicum distantiflorum Rich. 



Panicum distantiflorum Rich, in Sagra, Hist. Cuba 11: 304. 1850. "Crescit in 

 graminosis montosis insulae Cubae." The type in the Paris Herbarium is labeled 

 "in montosis ins. Cubae," and was received from Sagra. In the same herbarium is a 

 specimen of Panicum megiston Schult., from Cayenne, which bears a slip with the 

 name "Panicum distantiflorum" accompanied by a diagnosis and drawings of spike- 

 lets. The diagnosis and drawings apply to the Cuban specimen and not to the very 

 different Cayenne specimen. It would appear that the drawings had been attached 

 to the wrong sheet. 



DESCRIPTION. 



Plants cespitose, glabrous; culms 60 to 80 cm. high, slender, wiry, compressed, pro- 

 ducing slender, sometimes fascicled branches from all the nodes; sheaths longer than 

 the internodes, but narrow and sheathing the joints only at 

 the base, flattened, a minute tuft of hairs on the auricles; 

 ligule a ring of very short hairs; blades erect, firm, narrower 

 than the summit of the sheath, linear to almost capillary, as 

 much as 30 cm. long, 1 to 2 mm. wide, mostly strongly invo- 

 lute, at least the lower commonly more or less curled, usually 

 with a few hairs at the base; panicles numerous, 2 to 7 cm. 

 long, very narrow, the branches appressed, scarcely overlap- 

 ping, the lower 8 to 15 mm. long, the branchlets bearing 1 to 

 3 subsessile spikelets, the setiform prolongation of the axis 

 rarely equaling the spikelet, usually not more than 1 mm. long; spikelets 1.5 mm. 

 long, 0.7 mm. wide, ellipsoid, acute, glabrous; first glume about half as long as the 

 spikelet, acute, strongly 5-nerved; second glume obtuse, two-thirds to three-fourths 

 as long as the fruit and the strongly 7-nerved, acute, sterile lemma; fruit 1.3 mm. long, 

 0.6 mm. wide, elliptic, pointed, finely rugose. 



Fig. 1. — P. distantiflorum. 

 From type specimen. 



DISTRIBUTION. 



Open rocky soil, Bahamas and Cuba; apparently rare. 



• Bahamas: Inagua, Hitchcock in 1890, Nash <k Taylor 893 (both in Field Mus. 

 Herb.). 

 Cuba: Playa de Cojimar, near Habana, Hitchcock 144; Colombia near Habana, 

 Leon 305b, 567; Santiago de Cuba, Leon 912, 917; Playa de Marianao, Leon 

 in 1909. 



