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572 GRAMINEJE. (GRASS FAMILY.) 
48. AMPHICARPUM, Kunth. 
Perennial flat-leaved grasses, with the spikelets nearly as in Panicum, but of 
two kinds; one perfect, but rarely fruitful, disposed in a simple terminal panicle 
or raceme; the other larger, pistillate or perfect, and borne at the summit of long 
runner-like radical peduncles. Lower glume minute or wanting. : 
1. A. Purshii, Kunth. Culms tufted, erect from fibrous roots, naked 
above ; leaves lanceolate, rather thin, clothed, like the sheaths, with spreading 
rigid hairs; upper flowers in a strict panicle; those at base of the culm perfect; 
grain ovoid or oblong, terete. (Milium amphicarpon, Pursh.) — Low sandy pine 
barrens, Georgia, and northward. Sept.— Culms 1°-3° high. Glumes of the 
upper flowers 5-nerved, of the lower one white, many-nerved. 
2. A. Floridanum, n. sp. Culms subterraneous, diffusely creeping; 
flowering branches erect (1°- 39 high), branching ; leaves linear-lanceolate, rigid, 
smooth; sheaths fringed on the margins; upper flower abortive, panicled or 
racemed, oblong (3" long), acute; glumes 5-nerved ; anthers of the radical flow- 
ers imperfect ; grain compressed-globose, pointed. — Banks of the Apalachicola 
River, Florida. Sept. and Oct. — Plant pale green. Paleæ of the radical flow- 
ers crustaceous at maturity. 
49. PANICUM, L. Panrc-Grass. 
Inflorescence spiked, racemose or panicled. Spikelets 2-flowered, naked (no 
involucre). Glumes 2, herbaceous; the upper one usually as long as the flow- 
ers, the lower smaller, often minute, or occasionally wanting. Lower flower 
staminate or neutral, of 1-2 pales ; the upper palea, when present, small and 
hyaline, the lower herbaceous and resembling the upper glume. Upper flower 
perfect, coriaceous, awnless, enclosing the free grain. Stamens 3. : 
$ I. DIGITARIA. — Inflorescence spiked: spikelets 2 — 3. together, imbricated on 
one side of a filiform rachis: lower flower of one palea, and neutral: glumes 
. — Shorter than the flowers : annuals. ren 
1. P. sanguinale, L. (Cnam-Gmass) Culms ascending from a diffusely 
creeping base; leaves thin, spreading, the lower part, like the sheaths, hairy; , 
spikes 5-10, spreading ; spikelets oblong, pointed ; glumes hairy on the mar- 
gins, the upper half as long as the flowers, the lower minute, or in var. VILLOSUM 
(Digitaria villosa, Ell., a smaller and more hairy form) wanting. — Cultivated 
grounds and waste places everywhere. May- Oct. 
..?. P. filiforme, L. Culms erect, sparingly branched (29 - 39 high) ; leaves 
linear, erect, and, like the sheaths, hairy ; spikes 2 — 5, alternate, erect, filiform ; : 
-Spikelets oblong, acute, scattered; upper glume half as long as the acute black- 
_ ish palea, the lower wanting. — Dry sandy soil, common. Aug. and Sept- 
Prorer. — Glumes 2, unequal, awnless : spikelets in panicles 
