ANDROPOGONE^. 43 



nsually 3 to many, digitate, all pedicellate or all sessile, not sub- 

 tended by a leaf-sheath. Floral glume usually stalklike . . 30 

 Our single species annual; racemes nodding on very slender 

 peduncles. 



Subgenus 8. Heteropogon (Persoon as a genus). Eacemes or 

 spikes solitary and terminal or lateral. Spikelets imbricated, 1-15 

 of tlie lowest pairs homogamous; awns large with sharp barbed 

 points. 



a. Annual 31 



a. Perennial 32 



Subgenus 9. Cymbopogox (Spreng. as a genus). Eacemes in 

 pairs, terminal or lateral, 1 sessile, always with 1-2 basal homog- 

 amous pairs (of 2 staminate spikelets), the other short-pedicelled, 

 with or without homogamous pairs, both together subtended by a 

 sheathing leaf, frequently arranged in a false panicle, interrupted 

 by leaves. Floral glume strongly awned 33 



1. A. gracilis Spreng. Syst. 1: 281 (182-1-). A very slender, 

 erect, tufted, glabrous perennial, 30-60 cm. higli. Sheaths terete; 

 ligule very short; blade convolute-setaceous, 10-20 cm. long. 

 Spikes solitary, 3-4 cm. long, the terminal one exserted, the lateral 

 ones distant, sheathed by narrow bracts 2-4 cm. long, the zigzag 

 racliis and jiedicels clothed with soft spreading hairs reaching be- 

 yond the sj^ikelets. Pedicel 4 mm. long bearing an awned spikelet 

 2 mm. long, consisting of a single glume. Sessile spikelets lanceo- 

 late, about 5 mm. long, first and second glumes equal, the former 

 2-toothed with 2 nerves toward each margin, the latter acute, 1- 

 nerved, the bent awn nearly 2 cm. long. 



Fla., Gctrher. Found in Florida and the West Indies. 



2. A. hirtiflorus Kunth. Eev. Gram. 2 : 569, t. 198 (1829). 

 Culms slender, 50-120 cm. high mostly with 2 branches above, 



each as well as the main stem bearing a single erect sjjike. Lower 

 sheaths often hirsute or barbed at the throat; blades sparingly 

 hairy, 10-20 cm. long, 3-5 mm. wide, the upper ones slender, 0-4 

 mm. long. Spike single, narrow, zigzag, 4-6 cm. long bearing 5-8 

 pairs of sj^ikelets, rachis and pedicels hairy throughout. First glume 

 of sessile s])ikelet 7-9 mm. long, lanceolate, 2-toothed margins invo- 



