ANDROPO(JONE.E. 61 



longer than the first, linear-oblong, keeled above, 5-nerved; third 

 shorter than the first, broadly oblong, obtuse, 2-nerved; fourth and 

 third equal, lance-oblong, ciliate, 3-nerved. 



Florida, Oliapman, Garher, Curtiss 3644. 



Subgenus 6. Chrysopogon" Hack. D. C. Monog. Phan. 6 : 547 

 (1889). Chrysopogon Trin. Fund. Agrost. 187 (1820). 



Fertile spikelets 1-flowered, sessile between two pedicellate, 

 staminate or barren spikelets at the end of the filiform, unequal, 

 simple or divided branches of a true terminal panicle, with some- 

 times 1-3 pairs of spikelets on the branch below the terminal 3. 

 Sessile sj)ikelets compressed, first glume largest, awnless, mem- 

 branous and many-nerved, or more rigid with the lateral nerves 

 prominent and often muricate; second narrower, obscurely keeled, 

 pointed or obtuse or produced into a fine straight awn ; third much 

 smaller, hyaline; fourth linear, entire or 2-toothed. with a short 

 or long awn. Grain compressed. Pedicellate spikelets obcom- 

 pressed, awnless or awned, with reduced glumes and usually one 

 staminate flower, sometimes reduced to a small rudiment or want- 

 ing. 



Perennials, excepting A. pauciflorus, with narrow leaf -blades; 

 mostly limited to tropical regions. 



29. A. pauciflorus (Chapm.) Hack. 1. c. Sorghum pauciflorum 

 Chapm. Coult. Bot. Gaz. 3 : 20 (1878). 



Annual; culms 80-110 cm. high, compressed, smooth, usually 

 branching near the base. Sheaths compressed-keeled, smooth, 

 shorter than the internodes, pilose along the margins above, often 

 tinged with violet; ligule siiort, ciliate; blade flat or becoming con- 

 duplicate, with a broad, subcordate base, attenuate-pointed, 12-18 

 cm. (the upper ones 2-3 cm.) long, 5-8 mm. wide, smooth, or the 

 mid-nerves setaceous, margins ciliate with hairs from tubercled 

 bases. Panicle exserted, 14-20 cm. long, broadly ovate, very loose, 

 lower rays in twos to fours, very slender, the longest about 7 cm. 

 long. Sessile spikelets 15-17 mm. long, with a callus 6 mm. long, 

 densely barbulate with rufous hairs, linear, oblong, obtuse, first 

 glume firm, truncate, margins involute, shining or punctulate on 

 the back, obscurely 5-nerved; second as long as tlie first, firm. 



