OKDElt CXLII. — GKAMINACK.E. 575 



equal. Seeds coated with the palccT. Flovrm in sjiiko^. ar- 

 ranged on one side of the rachis. 



1. P. FLu'iTANS, (Kunth.) {CercnaJluUana^YW.) .SVo/i procumbent, 

 creeping, as.surgmt, glabroiis. Leaves scabrous, 2 — 3 inclu's lontj, slight- 

 ly glaucous beneath; sheaths hairy at the base; spikes miinerou'*, 20 — 

 30. recurved; r;ichis with the flowers arranged on the uj'jH'r snifnee 

 Glumea dotted, white. Paleoc equal; the interior one flat, the exterior 

 convex. — ^. Sept. — Nov. Swamps. 1 — 3 feet. 



2. P. Walteria'xum, (Schu.) {P. vaginatxan, Ell.) Stnn orce{»in(», 

 glabrous, branching. Leaves linear, short, the sheaths of the upper 

 leaves longer than the joints; spikes 1 — 2, one of them sessile. — If. 

 Through the summer. Damp soils, low country. 12 — 18 inches. 



3. P. filifor'me, (Swartz.) {Digifarla filifonnis, Ell.) Sfnn creet, 

 glabrous. Leaves narrow-lanceolate, slightly soal)rous, and Imiry on the 

 upper surface ; sheath hairy ; spikes alternate, filiform, sometimes very 

 long. Glumes pubescent, nearly equal. — 11. Sept. — Oct. On poor 

 lands. 1 — 2 feet. 



4. P. seroti'num, (Flue.) Spikes about 5, approximate; rachis flat; 

 spikelets rather broad. Ghnne elliptic lanceolate, acute, pubescent. 

 Cidno decumbent ; sheaths pilose. — C;u'. 



5. P. xota'tum, (Flue.) Spikes 2, conjugate ; raciiis flat ; sj)ikelet8 

 narrow. Glumes ovate, obtuse. — Car. 



6. P. DiSTicnuM, (Ell.) Stem prostrate, croopinir, geniculate. Lraves 

 short, shining ; sheath with the throat hairy ; spikes 2—4. Glnnus 

 lanceolate.— If. Through the summer. In damp soils. Common. 



Joint-grass. 



7. P. Michauxia'num, (Kunth.) {Milium paspaloides, Ell.) Sinn 

 ascending and decumbent, compressed, glabrous. Leaves ciliate, gla- 

 brous, 3 — 6 inches long; spikes digitate, conjugate. Glumes glabrous 

 ovate-lanceolate, acute. Falea> equal, shorter than the glumes. Seed 

 ovate, compressed. — If. June — Sept. Low country. 1 — 2 feet. 



8. P. trista'chyum, (Leconte.) Glabrous, creeping, erect in water, 

 prostrate on land. Leaves short, narrow, smooth ; sheaths broa.l, 

 bearded at the orifice ; spikes about :<, naked at tlie base. Glumes 

 ovate, in two series. — Geo. 



9. P. furca'tum, (Flue.) Spikes 2, conjugate ; rachis lri(p>etrous. 

 Glumes ovate-lanceolate, acuminate, smooth.— Car. and soutlnvard. 



10 P L^'vE, (Mich.) Stem ereet, glabrous. Leaves shot t, lanceolate, 

 glabrous, hairv at the throat ; spikes 3—6. Floieers 1 from each head ; 

 racliis a little hairy at the base.— If . June— Sept. Damp pa«^turcs. 1 

 —2 feet. . 



11 P Boscia'num, (Flue.) Spikes numerous; rachis fl.nt, straight ; 

 spikelets lateral. Glumes obtuse, nearly round, smooth, 5-nerved. 

 Leaves hairy at the base. — Car. 



12 P SET.\'CEUM, (Mich.) >S<m erect, slender, glabrous. Xrair* vil- 

 lous narrow; sheath villous ; spikes usually solitary. hUnccrs ^x^ two 

 rows. Peduncle long. Glume equal, 8— Snerved, minut. ly pubescent, 

 — n. June— Aug. Dry soils. Connnon. 



13. P. DASYPiiyL'u-M, (Ell.) 5/m decumbent, glabrou... Zr.nr. hairy 

 broad; sheaths shorter than the joints; spikes 2-3. alternate. (jlumr» 

 3-nerved, oval, pubescent. — July to Get. 



