ORDER CXLII. GRAMINACE.E. 577 



flowered, perfect and sterile ; valves acute, hairy. PaUcn of the slciile 

 floret \.— n. Aug.— Sept. On the sea-islands. 4— G feet. 



2. P. sanguina'lis, (L.) {Digitarla sanguhtalh, Scop.) Stem decum- 

 bent and assurgent, geniculate, taking root at the joints. Lravcs hairv, 

 with the sheaths shorter than the joints, sometimes purple ; si)ik('H 

 digitate, spreading, 4 — 6. Glumes glabrous, exterior ones small. J'a- 

 lece with the valves equal, lanceolate. — 0. Through the sununcr. 

 Cultivated grounds. Very common. Crabgraas. 



§ 2. Spikes racemose. 



3. P. Elliottia'num, (Schult.) (P. gibbum, Ell.) Stern erect, gla- 

 Drous. Leaves linear-lanceolate, pubescent. Flowers in appressed ra- 

 cemes. Glumes '2-flowered, perfect and sterile. Falan of the peifect 

 flower about half the length of the glumes. — <3. Through the summer. 

 Damp soils. Common. 1 — 2 feet. 



§ 3. Branches paniculate, more or less divided ; spikelcls solitary, scat- 

 tered. 



4. P. Ignora'tum, (Kunth.) (Aulaxant/nts ciliatus, Ell.) Stem erect, 

 glabrous, compressed toward the base. Leaves linear, ciliate, glabrous ; 

 sheath ciliate, hairy at the throat. Glumes villous. Palciv brown, 

 nearly black when mature. — %. Sept. — Oct. Pine-barrens. 1 — 2 ft. 



5. P. ru'fum, (Kunth.) {Axdaxanthns rufus. Ell.) Stem erect, larger 

 than the preceding. Leaves glabrous. Panicle large. Glumes cov- 

 ered with long, reddish-brown hair. — If. Aug. — Sept. Damp soils, 

 2—3 feet. 



6. P. deb'ile, (Poir.) {P. hians. Ell.) Stem slender, decumbent, gla- 

 brous. Leaves linear, ciliate near the base ; sheaths short, contracted 

 and pubescent at the throat. Flowers in racemose panicles. Glumes 

 ovate, acute, 2-flowered ; valves of the sterile floret long, of the fertile 

 ovate, cartilaginous. — 0. Aug. — Oct. Pine-barrens, Common. 10 

 — 15 inches. 



7. P. prolif'erum, (Lam.) {P. geuicidatum, Muhl.) Stem assurgent, 

 geniculate, branching, large. Leaves long, hairy, and scabrous on the 

 upper surface, glabrous beneath. Floivers in large panicle.*, difl"use. 

 Glumes I'^ow ex Qd. — If. Aug. — Oct. Wet soils. 3 — 6 feet. 



8. P. viRGA'TrM, (L.) Stem erect, glabrous. Leaves somewhat serru- 

 late, long; sheaths shorter than the joints. Panicle large, with the 

 branches often verticillate. Glumes 2-flowereil, perfect arul sterile, 

 with an accessory valve. — If. Aug. — Sept. Sea-coast, 4 — 6 feet. 



9. P. scABRTUs'cuLUM, (Ell.) Stem erect, large, .somewhat pubescent, 

 scabrous. Leaves linear-lanceolate, i)ubescent hetieath, serrulate; 

 sheaths pubescent, hairy at the throat Panicles large, expanding. 

 Peduncles glabrous. Glumes 2-flowered, perfect and sterile. — U. 

 Sept. — Oct. Low country of Geo. 2 — 3 feet. 



10. P. multiklo'rum, (Poir.) Smooth. Panicle dense, many-flow- 

 ered. Flowers sub-acute, oblong, small; branches rough. L(ate$ 

 broad, linear, smooth. — Car. 



11. P, ama'rum, (Ell.) Stem erect, stout, glabrou-^. Leaves flat, 

 thick; throat of the sheatli contracted, purple. Panicle large. Flow 

 ers large. Peduncles glabrous. Glumes 2-flowore(l, tinged with pur- 



