Jennings: Contribution to Botany of Isle of Pines. 51 



Leaves emersed, arising from a strong horizontal rhizome, the 

 petioles about 15 to 20 cm. long, the blades about 6 to 10 cm. long by 

 3 to 5 mm. wide, thick, pseudo-penninervate, with usually 5 nerves, 

 the apex narrow but obtuse, scape simple, 6 to 6.5 dm. tall, the 

 whorls of the inflorescence 4 to 7 in number, peduncles of the stami- 

 nate flowers 1.5 to 2 cm. long, slender, ascending, those of the pistillate 

 flowers about 8 to 17 mm. long, somewhat thicker than those of the 

 staminate flowers, bracts ovate, acute, strongly veined, dorsally 

 minutely papillose, 8 to 13 mm. long, sepals obtuse, about 6 mm. 

 long, petals about 1.5 cm. long, anthers slightly shorter than the 

 very sparingly pubescent filaments, mature achenes rounded-obovate, 

 about 2 mm. long by 1.2 mm. wide, margined all around by a lighter 

 colored wing, the beak about 0.5 mm. long, spreading horizontally 

 from the apex of the achene, but with the extreme tip usually upturned. 



Family GRAMINE.^. 



Key to the Species Enumerated. 



(Adapted from Hitchcock, Grasses of Cuba.-) 



Series I. Paniceae. 



Spikelets i- or rarely 2-flowered; if 2-flowered the terminal floret perfect, the 

 lower staminate or neutral; rachilla articulated below the glumes; spikelets not 

 laterally compressed. 



Lemma and palea hyaline; glumes more or less indurated, the first largest; sterile 

 and fertile lemma alike in texture. 

 Joints of the rachis much thickened and excavated to receive the spikelets. 



68. Hackelochloa granularis. 

 Joints of the rachis not thickened nor excavated. 



Spikelets all alike, perfect; panicle plume-like. .69. Imperata hrasiliensis. 

 Spikelets not all alike. 



Racemes of several to many joints, at least some of the racemes 

 sessile. 

 Racemes numerous in a leafless terminal panicle. 



73. Andropogon leucopogon. 

 Racemes 1-4, solitary or fascicled from spathes. 

 Racemes solitary. 



Spikelets awnless 75. Andropogon spathiflorus. 



Spikelets awned 72. Andropogon gracilis. 



Racemes 2-4 from each spathe. 



Spathes numerous in a large corymb. 



Spikelets awnless 70. Andropogon bicornis. 



Spikelets long-awned. . . .71. Andropogon tenuis patheus. 



2 Hitchcock, A. S. Contributions from the United States National Herbarium, 

 Xn, 1909, pp. 183-258. 



