Spikelets moncious, in jointed unilateral spikes, staminate above and fertile below. Staminate spikelets in pairs, sessile at each triangular joint of the narrow rhachis, both alike, 2-flowered, longer than the joints; glumes 4, coriaceous, the lower (outer) one nerved, the second boat-shaped, the upper with the palets very thin and membranaceous, awnless; anthers opening by 2 pores at the apex. Pistillate spikelets 2-flowered (the lower flower neutral), single and deeply imbedded in each oblong joint of the cartilaginous thickened rhachis, occupying a boat-shaped recess which is closed by the polished and cartilaginous ovate outer glume, the inner glume much thinner and pointed, the upper with the palets very thin and scarious, pointless. Styles united; stigmas very long (purple), hispid. Grain ovoid, free.--Culms stout and tall, solid, from very thick creeping rootstocks. Leaves broad and flat.

Spikes axillary and terminal, separating spontaneously into joints at maturity. (Name from t???, _to rub_, perhaps in allusion to the polished fertile spike.)

1. T. dactylodes, L. Spikes (4--8' long) 2--3 together at the summit (when their contiguous sides are more or less flattened), and also solitary from some of the upper sheaths (when the fertile part is cylindrical); in var. MONOSTaCHYUM, the terminal spike also solitary.--Moist soil, from Conn. to Penn. and Fla., near the coast, and from Ill. southward. Aug.--Culm 4--7 high; leaves like those of Indian Corn. This is one of our largest and most remarkable Gra.s.ses; sometimes used for fodder at the South.

12. ROTTB'LLIA, L. f. (Pl. 16.)

Spikelets in pairs at each joint of a terete slender spike, awnless; one imperfect or rudimentary on a short and thick appressed pedicel; the other sessile and imbedded in an excavation of the joint of the rhachis, 1-flowered or rarely with a second staminate flower. Glumes 4, obtuse, the outer hard and cartilaginous, with a transverse depression next the base, the inner one boat-shaped and membranaceous, the 2 upper thin and delicate. Stamens 3. Styles 2.--Tall or coa.r.s.e perennials, with rigid stems, and single cartilaginous spikes terminating the stem and axillary branches, chiefly subtropical. (Named for _Prof. C. F. Rottboell_, an excellent Danish botanist, who wrote much upon Gramineae, Cyperaceae, etc.)

1. R. rugsa, Nutt. Culm flattish, 2--4 high; leaves linear; spikes 1--2' long, the lateral ones on short cl.u.s.tered branches in the axils, often partly included in the sheaths of the leaves; sterile flower neutral; lower glume transversely rugose.--Low pine-barrens, from S. Del. (_W. M. Canby_) southward near the coast. Sept.--Oct.

13. ERIaNTHUS, Michx. WOOLLY BEARD-GRa.s.s. (Pl. 14.)

Spikelets spiked, in pairs upon each joint of the slender rhachis, one sessile, the other pedicelled, both 1-flowered, alike. Glumes 4, the 2 lower nearly equal, one 4--5-nerved, the other many-nerved; the 2 upper hyaline, one empty, the upper awned from the tip. Stamens 3. Grain free.--Tall and stout reed-like perennials, with the spikes crowded in a panicle, and clothed with long silky hairs, especially in a tuft around the base of each spikelet (whence the name, from ?????, _wool_, and ?????, _flower_).

1. E. saccharodes, Michx. (Pl. 14, fig. 1, 2.) Culm (4--6 high) woolly-bearded at the joints; _panicle contracted; the silky hairs longer than the spikelets_, shorter than the awn; stamens 2. (E.

alopecuroides, _Ell._)--Wet pine-barrens, from N. J. and Ill. southward; rare. Sept., Oct.

2. E. brevibarbis, Michx. Culm (2--5 high), somewhat bearded at the upper joints; _panicle rather open_; silky hairs shorter than the spikelets.--Low grounds, Va., and southward.

14. ANDROPGON, Royen. BEARD-GRa.s.s. (Pl. 14.)

Spikelets in pairs upon each joint of the slender rhachis, spiked or racemed, one of them pedicelled and sterile (staminate, pistillate or neutral), often a mere vestige, the other sessile, 1-flowered and fertile; lower glume the larger, coriaceous and nerved, blunt, the second carinate and acute, the 2 upper hyaline, the flowering glume awned from the tip. Stamens 1--3. Grain free.--Coa.r.s.e, mostly rigid perennials, mostly in sterile or sandy soil; with lateral or terminal spikes commonly cl.u.s.tered or digitate; the rhachis hairy or plumose-bearded, and often the sterile or staminate flowers also (whence the name, composed of ????, _man_, and p????, _beard_).

[*] _Spikes digitate, thickish, short-bearded, the sterile spikelet staminate; stamens 3._

1. A. furcatus, Muhl. (Pl. 14, fig. 1--3.) Tall, 3--4 high, rigid, the naked summit of the culm (and usually some lateral branches) terminated by 2--5 rigid spikes; spikelets approximate, appressed; hairs at the base of the fertile spikelet, on the rhachis and on the stout pedicel of the awnless staminate spikelet short and rather spa.r.s.e; awn of fertile flower long and bent; leaves flat, roughish, the lower ones long. ("A.

provincialis, _Lam._")--Common in dry sterile soil. Aug.--Oct.

[*][*] _Spikes with slender often zigzag rhachis, silky-villous._

[+] _Single and scattered along the branches, with the silky hairs shorter than the flowers; sterile spikelet conspicuous but mostly neutral; the fertile triandrous._

2. A. scoparius, Michx. Culms slender (1--3 high), with numerous paniculate branches; lower sheaths and narrow leaves hairy; spikes slender, scattered, mostly peduncled (1--2' long), very loose, often purplish, silky with lax dull-white hairs; sterile spikelet awn-pointed or awnless; the fertile about half the length of its twisted or bent awn.--Dry ground. July--Sept.

3. A. maritimus, Chapm. Smooth and glaucous; culms ascending from creeping rootstocks, 1--1 high; leaves rather rigid, divaricate, their compressed sheaths imbricated; panicle short; peduncles included within the conspicuous bracts; rhachis and pedicels copiously ciliate with spreading hairs; glumes larger, 3--4" long.--Sandy sea-coast; Cape May, and south to Fla.

[+][+] _In pairs or cl.u.s.tered; the copious soft-silky hairs much longer than the flowers; sterile spikelet a small neutral rudiment (in n. 4 and 5), or altogether wanting on the very plumose-hairy pedicel; fertile flower monandrous, its awn capillary; leaves narrow, the lower or their sheaths often rather hairy._

4. A. argenteus, Ell. Smooth; culms rather slender (1--3 high); _spikes_ in pairs (rarely in fours) on short mostly exserted _and loosely paniculate peduncles, densely flowered_ (1--2' long), _very silky with long bright white hairs_. (A. argyraeus, _Schultes._)--Md. to Va., near the coast, and southward.

5. A. Elliottii, Chapm. Closely resembling the last; sheaths and leaves villous; upper nodes of the branches densely bearded.--Md. to Fla. and Tex.

6. A. Virginicus, L. Culm flattish below, slender (2--3 high) _sparingly short-branched above_, sheaths smooth; _spikes 2 or 3 together in distant appressed cl.u.s.ters, shorter than their sheathing bracts_, weak (1' long), the spikelets loose on the filiform rhachis, the soft _hairs dull white_. (A. dissitiflorus, _Michx._ A. v.a.g.i.n.atus, _Ell._, a form with larger and inflated sheaths.)--Sandy soil, E. Ma.s.s.

to Va., Ill., and southward. Sept., Oct.

7. A. macrourus, Michx. Culm stout (2--3 high), _bushy-branched at the summit_, loaded with very numerous _spikes forming thick leafy cl.u.s.ters_; sheaths rough, the uppermost hairy; flowers nearly as in the preceding; the sterile spikelet of each pair wholly wanting, its pedicel slender and very plumose.--Low and sandy grounds, N. Y. to Va., near the coast, and southward.

8. A. lagurodes, DC. Culms slender, tall, the elongated peduncle bearing numerous sessile spikes in a spike-like panicle 2--4' long; spikes slender, 1' long or more, very silky; spikelets glabrous, the sterile a narrow convolute empty glume.--Central Kan. to Tex. and Mex.

[+][+][+] _Spikes digitate-cl.u.s.tered, very silky; sterile spikelet larger than the fertile one._

9. A. Hallii, Hackel. Culm stout, 2--3 high; lateral peduncles few, scarcely exserted from the sheaths; spikes 2--5, 1--3' long, dense; spikelets 3--4" long.--Central Kan. to Dak., and westward.

15. CHRYSOPGON, Trin. (Pl. 14.)

Spikelets in pairs on the ramifications of an open panicle (those at the ends of the branches in threes), the lateral ones pedicellate, sterile or often reduced merely to their pedicels; only the sessile middle or terminal one fertile, its glumes coriaceous or indurated, sometimes awnless; otherwise nearly as in Andropogon. Stamens 3. (Name composed of ???s??, _gold_, and p????, _beard_.)

1. C. nutans, Benth. (INDIAN GRa.s.s. WOOD-GRa.s.s.) Root perennial; culm simple (3--5 high), terete; leaves linear-lanceolate, glaucous; sheaths smooth; panicle narrowly oblong, crowded or loose (6--12' long); the perfect spikelets at length drooping (yellowish or russet-brown and shining), clothed especially toward the base with fawn-colored hairs, lanceolate, shorter than the twisted awn; sterile spikelets small and imperfect, deciduous, or reduced to a mere plumose-hairy pedicel.

(Andropogon avenaceus, _Michx._ Sorghum nutans, _Gray_.)--Dry soil; common, especially southward.

16. PHaLARIS, L. CANARY-GRa.s.s. (Pl. 13.)

Spikelets crowded in a cl.u.s.tered or spiked panicle, 1-flowered. Glumes 5, the third and fourth reduced to mere rudiments (a scale or a pedicel), one on each side, at the base of the flowering glume and palet, which are flattish, awnless and shining, shorter than the equal boat-shaped and keeled persistent empty glumes, finally coriaceous or cartilaginous, and closely enclosing the flattened free and smooth grain. Stamens 3.--Leaves broad, mostly flat. (The ancient name, from fa???, _shining_, alluding to the shining seed.)

-- 1. PHALARIS proper. _Panicle very dense, spike-like; glumes wing-keeled._

P. CANARIeNSIS, L. (CANARY-GRa.s.s.) Annual, 1--2 high; spike oval; empty glumes white with green veins, the rudimentary ones small lanceolate scales.--Waste places and roadsides; rare. (Adv. from Eu.)

-- 2. DiGRAPHIS. _Panicle branched, the cl.u.s.ters open in anthesis; glumes not winged on the back._

1. P. arundinacea, L. (REED C.) (Pl. 13, fig. 1, 2.) Perennial, 2--4 high; leaves flat (3--5" wide); glumes open at flowering, 3-nerved, thrice the length of the fertile flower; rudimentary glumes reduced to a minute hairy scale or pedicel.--Wet grounds; common, especially northward. June, July.--Var. PiCTA, the leaves striped with white, is the familiar RIBBON-GRa.s.s of the gardens. (Eu.)

17. ANTHOXaNTHUM, L. SWEET VERNAL-GRa.s.s. (Pl. 13.)

Spikelets spiked-panicled, 1-flowered. Glumes 5, the third and fourth empty, hairy, 2-lobed and awned on the hack, the flowering glume and palet small, hyaline and obtuse; basal glumes persistent, very thin, acute, keeled, the lower half as long as the upper. Squamulae none.

Stamens 2. Grain ovate, adherent. (Name compounded of ?????, _flower_, and ?????, _of flowers_. _L._)

A. ODORaTUM, L. Spikelets (brownish or tinged with green) spreading at flowering-time; one middle glume bearing a bent awn from near its base, the other short-awned below the tip.--Meadows, pastures, etc. Low slender perennial; very sweet-scented in drying. May--July. (Nat. from Eu.)

18. HIERoCHLOE, Gmelin. HOLY GRa.s.s. (Pl. 13.)

Spikelets 3-flowered, open-panicled, the two lower (lateral) flowers staminate only, 3-androus, sessile, the carinate glumes often awned on the middle of the back or near the tip, the uppermost flower perfect, short-pedicelled, scarcely as long as the others, 2-androus, awnless.

Basal glumes persistent, carinate, acute, somewhat 3-nerved, equalling or exceeding the spikelet.--Perennials; leaves flat. (Name composed of ?e???, _sacred_, and ????, _gra.s.s_; these sweet-scented gra.s.ses being strewn before the church-doors on saints' days, in the North of Europe.)

1. H. borealis, Roem. & Schultes. (VANILLA or SENECA GRa.s.s.) (Pl. 13, fig. 1, 2.) Panicle somewhat one-sided, pyramidal (2--5' long); peduncles smooth; staminate flowers with the glume mucronate or bristle-pointed at or near the tip; rootstock creeping.--Moist meadows, chiefly northward near the coast and along the Great Lakes. May.--Culm 1--2 high, with short, lanceolate leaves. Spikelets chestnut-color; the staminate flowers strongly hairy-fringed on the margins, and the fertile one at the tip. (Eu.)

2. H. alpna, Roem. & Schultes. Panicle contracted (1--2' long); one of the staminate flowers with its glume barely pointed or short-awned near the tip, the other long-awned from below the middle; lowest leaves very narrow.--Alpine mountain-tops, N. Eng., N. Y., and northward. July.

(Eu.)

19. ARiSTIDA, L. TRIPLE-AWNED GRa.s.s. (Pl. 8.)