64G GRAMINE.E. (GRASS FAMILY.) 



* Spikes erect : the rharliis Jiliform and nearly terete. 



1. P. fillfdrme, L. Culms very slender (lo-2° hiyli), upright; lower 

 sheaths liuiry ; sjiiLxs -2 - 8, alternate, approximated, filiform; spikelets oblong, 

 acute (^" long) ; lower glume almost wanting. — Dry sandy soil, Massachusetts 

 to New Jersey along the coast, Illinois, and southward. Aug. 



* * Sjiike.i spreadiii;/ ; the rhachis Jlut and thin. 



2. P. Gi-\niaiM, Gaudin. Culms spreading, prostrate, or sometimes erect 

 (5'- 12' long), gl;ibrous; sj>i/ces 2-6, ividelij divenjing, ne.irly digitate; spikelets 

 ovoid (about I'' long) ; upper r/lume equalling thejloiver, the lower one almost want- 

 ing. — Cultivated grounds and waste places : common, especially southward : in 

 some places appearing as if indigenous. Aug., Sept. (Nat. from En.) 



3. P. s.vnguinXle, L. (Common Crab- or Finger-Gr.\ss.) Culms erect 

 or spreading (1° - 2° high) ; leaves and sheaths glabrous or hairy ; spi/as 4 - 15, 

 spreading, digitate ; spikelets oblong ( 1 h" long) ; upper glume lialfthe length of the 

 flowtr, the lower one small. — Cultivated and waste grounds. Aug. - Oct. (Nat. 

 from Eu.) 



§ 2. PANICUM proper. Sj)ikelets scattered, in panicks, awnless. 

 * Panicle elongated and racemose, wand-like or pyramidal ; the numerous and usually 



pointed spilcclets short-pedicelled, excepting No. 7 and 8. 



•«- Sterile ^flower neutral and of 2 pal ets, fully twice the length of the lower glume: 



spikelets small (1" or H" long) : root perennial. 



4. P. aneeps, Michx. Culms fat, upright (2° -4° high); leaves rather 

 broadly linear (l°-2 long, 4'' -.5" wide), smooth ; panicle contracted-pyramidal ; 

 spikelets ovat^-lanceolate, pointed, a little curved ; upper glume .5 - 7 -nerved; neutral 

 flower one third longer than the perfect one. — Wet sandy soil, New Jersey and 

 Penn. to Virginia, and southward. Aug. — Too near the next : spikelets and 

 branches of the panicle longer. * 



.5. P. agrostoides, Spreng. Culms flattened, upright (2° high) ; leaves 

 long, and with tlic sheaths smooth ; panicles terminal and often lateral, pyram- 

 idal (4' -8' long) ; the spikelets racemose, crowded and one-sided on the spread- 

 ing branches, ovate-oblong, acute (purplish) ; upper glume b-nerved, longer than the 

 neutral flower which exceeds the perfect one ; perfect flower bearded at the apex. 

 (P. agrostidiforme, Lam. ? P. niultiflorum, Potr.) — Wet meadows and shores, 

 E. Massachusetts and New York (Oneida Lake, ^1. //. Curtiss) to Illinois, and 

 common southward. Aug. 



-t- •<- Sterile flower neutad and <f a single ]>aJef, much lunger than the lower glume; 

 spikelets ^"-1|" long; annuals crept No. 8: leaves flat; shea' Its flattened. 



++ Gliilirons and smooth throughout; spikelets croud- d, appressed, short -pedicelled. 



6. P. proliierum, Lam. Culms usually thickish and rather succulent, 

 branched, geniculate and ascending from a procumbent base ; sheaths flattened ; 

 ligulc ciliate ; panicles terminal and lateral, compound, pyramidal, the slender 

 primary branches at length spreading ; spikelets p:ile green, rarely purplish ; 

 lower glume broad, J to \ the length of the upper ; neutral flower little longer 

 than the perfect one. —Marshy river-banks and shores, especially when brack- 

 ish, but also in the interior, from jNIass. and Illinois southward. Aug. 



