576 ORDER CXLII. GRAMIXACEiE. 



14. P latifo'lium, (L.) Smooth. Culm nearly erect. Leaven long, 

 broad, ciliate ; sheath naked, except at the orific-e ; spikes 2 — o, alter- 

 nate, pilose at the base. Glumea orbicular, in three serie?, the inter- 

 mediate pedicellate ; raehis narrow. — Car. 



15. P. ten'ue. Erect, glabrous. Leaves long, narrow ; spikes 4 — 5, 

 alternate, spreading, pilose at the base. Glumes orbicular, in three 

 eeries ; raehis flexuous, narrow. — Geo. and northward. 



16. P. aruxdixa'ceum, (Poir.) Smooth. Spikes alternate, elongated ; 

 spikelets in three series. Glumes obtuse, equal. Leaves ensiform ; 

 margins rough. — Car. 



17. P. ALTis'siMUM, (Lee.) Smooth, erect, high. Leaves\ong\ sheaths 

 ciliate at the base and at the orifice ; spikes 4 — 5, alternate, erect, pi- 

 lose at the base. Glumes large, orbiculate, in two series; raehis broad. 

 — N. Car. 



18. P. macrosfer'mum, (Flue.) (P. Floridanum, Mich.) Stem erect, 

 glabrous. Leaves long, the lower ones hairy and scabrous, the upper 

 ones becoming nearly glabrous ; throat of the sheath villous ; spikes 

 generally 3 ; raehis hairy at the base. Flowers 1 — 2 from each bud. — 

 If. June — Sept. Common. 3 — 4 feet. 



19. P. lentif'erum, (Lam.) (P. prcccox, Walt.) Stem erect, gla- 

 brous. Leaves linear-lanceolate, glabrous ; spikes numerous, with the 

 flowers crowded, two from each bud, and one of them sessile; raehis 

 hairy at the base. Glmnes orbicular, glabrous. — If. May — Aug. 

 Damp soils. 1 — 2 feet. 



.20. P. mucroxa'tum, (Mich.) Culm glabrous, creeping on the land 

 and swimming in the water. Jjcaves broad, ciliate at the base ; sheaths 

 broad, swollen, ciHate ; spikes numerous, narrow, the lowest verticil 

 late, others scattered, naked at the base. Glumes ovate, small, in two 

 series. — Geo. to Miss. P. natans, Leconte. 



21. P. purpuras'cexs, (Ell.) Stevi decumbent and erect, branching, 

 glabrous. Leaves long, hairy at the base, dark purple ; spikes numer- 

 ous. Flowers crowded, two from each bud ; raclais hairy at the base. — 

 1i. July — Oct. Common. 12 — 18 inches. 



22. P. uxdula'tiim, (Poir.) (P. plicatulum, Mich.) Leaves somewhat 

 keeled; margins scabrous, ciliate at the base; sheaths smooth; spikes 

 numerous ; raehis flat, glabrous ; margins scabrous ; spikelets in 2 — 4 

 series ; inferior glumes pubescent, superior glabrous. — Geo. and Flor. 



Genus X.— PAN'ICUM. L. 



(The ancient Latin name for some of the species.) 



Glumes 2, unequal, the lower one very small ; the lower 

 florets usually abortive or bearing stamens only. Palece con- 

 cave, equal, beardless. Seed coated with the paleae. Flowers 

 in loose, scattered panicles or spikes. 



§ 1. Spikes digitate. 



1. P. mol'le, (Mich.) {Eriochloa mollis, Kunth.) Stem erect, pubes- 

 cent toward the summit and all the joints. Leaves glabrous, with the 

 throat of the sheath ciliate. Flojvers in spikes or racemes. Glumes 2- 



