TRIANDRIA DIGYNIA. 305 



L. oryzoides : panicle diffuse, sheathed at the base ; flowers triandrou*, 



spreading ; keel of the glumes conspicuously ciliate. 

 HAB. Ditches and swamps. August September. 7J.; Culm 3 5 

 feet high ; leaves and sheaths very scabr. ; Jl. whitish. 



29. PASPALUM. 



P. ciliatifolium : culm decumbent; leaves hairy and ciliate; sheath 

 hairy ; spikes 1 2, rather loose, indistinctly 3-rowed. 



HAB. Sandy fields. September % ; A foot and a half long, simple ; 

 term, spikes on a long pedunc. ; Jlower plano-convex, on bifid pedi- 

 cels ; rack, reflex. 



P. setaceum : culm erect ; ' leaves and sheaths villose ; spikes generally 

 solitary ; flowers in 2 rows. 



HAB. Sandy fields. September 7].; culm 1 2 feet high, simple: 

 rachis convex on the back. 



30. MILIUM. Millet-grass. 



M. pungens : culm erect ; leaves lanceolate, very short, pungent, at 

 length involute ; panicle contracted ; branches generally by pairs, 2- 

 flowered ; flowers awnless, ovate ; corolla hairy. 



HAB. Rocky hills. May Tj.; 12 18 inches high, rigid; culm leaves 

 very short ; panicles few Jlowers ; style ^parted ; nectary lanceo- 

 late. 



31. PIPTATHERUM. 



P.nigrum: panicle simple ; flowers racemose, ovate-lanceolate ; corolla 

 black, hairy ; awn as long again as the valves. 



HAB. Mountains and rocky places. August. Tj. ; Culm 2 3 feet 

 high, leafy ; panicles few-Jlowered, Jlexuous ; nect. ovate-lanceo- 

 late. 



32. STIPA. Feather-grass. 



S. avenacea : leaves setaceous ; panicle spreading, somewhat secund ; 



branches mostly by pairs, a little divided; calyx as long as the seed, 



awn naked. 

 HAB. Sandy woods. June, flj.; 2 feet high; leaves mostly radical, 



narrow ; corolla stipit. brownish ; awn 2 3 inches long. 



33. ARISTIDA. 



A. dichotoma: cespitose; culm dichotomous; flowers racemose-spiked; 

 lateral awns very short ; the intermediate one contorted. 



HAB. Fields and dry hills. September. ; 812 inches high, slen- 

 der ; corolla \-valved ; lat. awns straight. 



A. purpurascens : culm filiform, erect, simple ; leaves very narrow, flat ; 

 flowers in a long spiked panicle ; awns nearly equal, twice the length 

 of the corolla, divaricate. 



HAB. Sandy fields and woods. September October. Qj. ; 2 feet high, 

 leaves filiform at the extremity ; panicles many-lowered, purple. 



34. MUHLENBERGIA. 



M. diffusa: culm diffuse, (decumbent;) leaves linear-lanceolate ; pan- 

 icle branched, appressed ; awns as long as the corolla. 



