8 POACEAK 



1. T. floridanum Porter. Plants 1 m. tall or less, the stem smooth, glabrous: 

 leaf -blades 4 dm. long or less, usually less than 5 mm. wide: spikes single, 

 slender, 8-20 cm. long: pistillate spikelets 6-7 mm. long, the outer scale acute 

 or acuminate: staminate spikelets 5-6 mm. long, the 2 outer scales oblong. 

 Pinelands, L. keys. [E. K.] GAMMA-GRASS. SESAME-GRASS. 



2. ANDEOPOGON L. Erect plants with spike-like racemes, which often 

 protrude from the side of a membranous spathe-like sheath. Sessile spikelet 

 of 4 scales, bearing a straight contorted or spiral awn, or sometimes awnless. 

 Pedicellate spikelet usually sterile, of 1 or 2 scales, sometimes of 4 scales and 

 enclosing a staminate or more rarely a perfect flower, or frequently entirely 

 wanting. BROOM-GRASS. BEARD-GRASS. SAND-GRASS. 



Sessile spikelets of all pairs, even the lowest, in all the racemes, alike. 

 Inflorescence oblong to oval or obovate, the branches many 

 times divided, the lower ones elongated, forming 1 or 

 more corymbiform masses ; upper stem-leaves usually 



equalling or exceeding the inflorescence. 1. A. tenuispatheus. 



Inflorescence long and narrow, commonly linear, the 

 branches not much divided nor the lower ones exces- 

 sively elongated, hence forming no corymbiform masses ; 



upper stem-leaves usually shorter than the inflorescence. 2. A. longiberbis. 

 Sessile spikelets of the lower pair or pairs differing from those 



above, staminate or empty, awnless. 3. A. ceriferus. 



1. A. tenuispatheus Nash. Stems 5-15 dm. tall: spathes 2.5-3 cm. long, 

 fastigately crowded: racemes in pairs, 1-2 cm. long, protruding from the side 

 of the broad spathe: sessile spikelet 34 mm. long, the awn 10-15 mm. long. 

 Edges of hammocks and lime-sinks, L. keys, L. S. keys. [E. K.] (Bah., 

 Cuba, Ant.) 



2. A. longiberbis Hack. Stems 5-10 dm. tall, tufted: leaf-sheaths appressed- 

 hirsute; blades 5 dm. long or less, 7 mm. wide or less, those on the innovations 

 densely appressed-hirsute, those on the stem more or less so beneath, rough 

 above: spathes 3-5 cm. long, usually considerably exceeding the racemes, com- 

 monly brown: racemes 3-4 cm. long, stout: sessile spikelet 4-4.5 mm. long, the 

 awn straight or nearly so, 12-16 mm. long. Pinelands, L. keys. [E. K.] 



3. A. ceriferus Hack. Stems 2 m. tall or less, smooth and glabrous, wax- 

 bearing at the nodes: leaf -blades 7 dm. long or less and 1 cm. wide: panicle 

 3-8 dm. long, narrow: spathes lanceolate, 1.5-2 cm. long: racemes about 6 mm. 

 long, linear-lanceolate. Hammocks, Elliott's Key. Nat. of S. Am. 



3. HOLCUS L. Perennial herbs or shrubby plants with large terminal 

 panicles, the primary branches verticillate. Spikelets of 4 scales, dorsally 

 compressed, pubescent or glabrous. Sessile spikelets with the 2 outer scales 

 indurated, the third and fourth hyaline, the latter awned or awnless. Pedicel- 

 late spikelet with the 2 outer scales firm-membranous, or rarely reduced to 1 

 or 2 scales and fruitless. [Sorghum Pers.] 



1. H. Sorghum L. Stems 1 m. tall or more : leaf -blades mostly 4-8 cm. wide : 

 panicle 1-3 dm. long, sometimes longer, the branches erect, or in some forms 

 drooping: sessile spikelets somewhat pilose, at maturity usually glabrous, 

 excepting the small pilose depression, the awn when present usually less than 

 1 cm. long, the other spikelet with a very short pedicel. Hammocks and cul- 

 tivated grounds, U. keys, L. keys. Nat. of the E. Indies. (Cuba, Ant.) 

 SORGHUM. 



4. SORGHASTBUM Nash. Usually tall perennial grasses, with terminal 

 panicles with the primary branches usually solitary and branched from the 

 base, hence appearing as if whorled. Sessile spikelets dorsally compressed, of 



