(GRASS FAMILY.) 629 



ing; spikes (2-4) approximate, 2-4' long, smooth or nearly so; spikelets 

 about V wide, 2-rowed. Moist soil, S. New Eug. to Ky., and southward. 



5. P. Floridanum, Michx. Stout, erect, 3-6 high, glaucous ; sheaths 

 and leaves more or less villous, the latter and the spikes erect or ascending ; 

 spikes (2 - 5) broader, 2 - 5' long, the smooth spikelets nearly 2" broad, in 2 

 rows. Moist soil ; Del. to Ma., Ark., and Tex. 



t- - Spikelets acute ; spikes several, racemose. 



6. P. dilatatum, Poir. Stout, erect, 2-5 high, villous at the top of the 

 sheath; spikes few on a naked peduncle, erect, 2-3' long; spikelets \" long 

 or more, the lower glume sof t-villous on the margin. Ya. to Tex. 



H- - -H- Spikelets acute; spikes always a pair at the summit of the naked 



peduncle. 



7. P. distichum, L. (JOINT-GRASS.) Nearly glabrous, rather glaucous; 

 culms ascending (about 1 high) from a long creeping base; leaves linear- 

 lanceolate (2-3' long) ; peduncle usually short; spikes short and closely-flow- 

 ered (9" - 2' long), often slightly separated ; rhachis flat on the back ; spikelets 

 ovate, slightly pointed (barely 1$" long), approximate on one side of the rhachis. 



Wet fields, Va. and southward. July - Sept. 



8. P. Elliottii, Watson. Culms ascending (1 - 2- high) from a creeping 

 base ; leaves lanceolate (3 - 6' long, 4 - 6" wide) ; spikes slender, rather sparsely 

 flowered (1-4' long), both sessile upon the long slender peduncle ; spikelets 

 ovate-lanceolate (2" long), on nearly opposite sides of the rhachis. (Milium 

 paspalodes, Ell. P. Digitaria, Chapm.; not Poir.) Va. and southward. 



4. ERIOCHLOA, HBK. (PI. 15.) 



Spikelets ovate, subsessile or shortly pedicelled upon one side of the rhachis 

 of a spike, with a callus at base and jointed on the pedicel, 1 -flowered. Glumes 

 3, the 2 empty ones slightly unequal, membranaceous, acute, the flowering one 

 shorter, indurated, obtuse, enclosing the free grain. Coarse tufted grasses, 

 with flat leaves, the spikes more or less scattered along a common peduncle, 

 and the pedicels and rhachis of the spike usually pubescent or hairy (hence 

 the name, from epiov, wool, and %x6a, grass). 



1. E. polystachya, HBK. Culms erect or decumbent, 2 high ; spikes 

 6-12, erect or ascending, 1-2' long, forming a compound spike 3-6' long; 

 spikelets glabrous, very shortly pedicelled, oblong-lanceolate, nearly 2" long. 



S. Kan. to Tex. and Mex. 



5. PANICUM, L. PANIC-GRASS. (PI. 13.) 



Spikelets jointed upon the pedicels, ovate, panicled, racemed, or sometimes 

 spiked, not involucrate, with one perfect and sometimes a second lower rudi- 

 mentary or staminate flower. Glumes 4, but the lower one usually short or 

 minute (rarely even wanting), and the third empty or sterile, membranaceo- 

 herbaceous. Upper flower perfect, closed, coriaceous or cartilaginous, usually 

 flattish parallel with the glumes, awnless (except in 3), enclosing the free 

 and grooveless grain. Stamens 3. Stigmas plumose, usually purple. (An 

 ancient Latin name of the Italian Millet, P. Italicum (now Setaria Italica), of 

 uncertain origin and meaning.) 



