120 



GRAMINEAE. 



Vol. I. 



Awns 3 times as long as the spikelets or less; column straight, rarely geniculate. 

 Awns 4-5 times as long as the spikelets, the column geniculate. 



nutans. 

 Elliottii. 



1: 58. 



1. Sorghastrum nutans (L.) Nash. Indian-grass. Fig. 274. 



Andropogon nutans L. Sp. PI. 1045. 1753. 

 Andropogon avenaceum Michx. Fl. Bor. Am. 



1803. 

 Sorghum nutans A. Gray, Man. 617. 1848. 

 Sorghum avenaceum Chapm. Fl. S. States, 583. i860. 



Chrysopogon avenaceus Benth ; Vasey, Grasses U. 

 S. 20. 1883. 



Sorghastrum nutans Nash, in Small, Fl. SE. U. b. 

 66. 1903. 



Culms erect, 3°-8° tall, smooth, the nodes 

 pubescent; sheaths glabrous, or the lower pubes- 

 cent ; blades 2° or less in length, 2"-8" wide, long- 

 acuminate, scabrous; panicle 4'-i2' long; branches 

 2-4' long, slender, erect-spreading; spikelets in 

 pairs, or in 3's at the ends of the branches, erect 

 or somewhat spreading ; first scale of sessile spike- 

 let 3"-4" long, acute, pubescent with long hairs; 

 second scale glabrous; awn s"-io" long, the 

 column straight. 



In dry fields, Maine to Manitoba, south to Florida 

 and northern Mexico. Aug-Sept. Wood-grass. Bushy 

 blue-stem. Wild oat-grass. 



2. Sorghastrum Elliottii (C. Mohr) Nash. 

 Long-bristled Indian-grass. Fig. 275. 



Sorghum nutans Linnaeanum Hack, in Mart. Fl. 



Bras. 2 3 : 276. 1883. 

 Chrysopogon Elliottii C. Mohr, Bull. Torrey Club 24: 



21. 1897. 

 Sorghastrum Linnaeanum Nash, in Small, Fl. SE. 



U. S. 66. 1903. 

 Sorghastrum Elliottii Nash, N. Am. Fl. 17 : 130. 1912. 



Culms 3°-4i° tall ; sheaths smooth and gla- 

 brous; blades ii° long or less, up to 5" wide, 

 very rough; panicle 6'-i2' long, the apex usually 

 nodding, its branches erect or nearly so, at least 

 the lower ones much exceeding the internodes of 

 the axis, 2Y-3' long, the ultimate divisions 

 straight; spikelets 3"-4" long, lanceolate, deep 

 chestnut brown at maturity, hirsute, the awn 

 i'-ii' long, the column- geniculate. 



In dry soil, Virginia and Tennessee to Florida and 

 Texas. 



9. HOLCUS L. Sp. PI. 1047. 1753. 



[Sorghum Moench, Meth. 207. 1704.] 



Annual or perennial grasses with long broad flat leaves and terminal ample panicles. 

 Spikelets in pairs at the nodes, or in 3's at the ends of the branches, one sessile and perfect, 

 the others pedicellate, and staminate or empty. Sessile spikelet consisting of 4 scales, the 

 outer indurated and shining, obscurely nerved, the inner hyaline, the fourth awned and 'sub- 

 tending a small palet and perfect flower, or palet sometimes wanting. Stamens 3. Styles 

 distinct. Grain free. [Name Greek, taken from Pliny.] 



About 10 species, of wide distribution in tropical and warm-temperate regions. Type species: 

 Holcus Sorghum L. 



