Part 202 (1/2)

10. S. airodes, Torr. Culm tufted, often stout, erect, --3 high; leaves strongly revolute and attenuate, rather rigid; panicle open and diffuse, broadly pyramidal, glabrous; spikelets solitary on slender pedicels, 1” long; lower glumes unequal, rather obtuse.--Neb. to Tex., and westward.

S. ASPERIFLUS, Thurb., a similar but smaller species, with thinner and shorter leaves very rough on the margin, the inflorescence scabrous, and spikelets smaller, with the glumes nearly equal, is very common westward, and probably occurs within our limits--as also S. CONFuSUS, Vasey (S. ramulosus of authors, not _Kunth_), a low slender annual, with very short culms and a delicate diffuse panicle, the very small spikelets (” long) on filiform-clavate pedicels.

[*][*][*] _Empty glumes almost equal; panicle racemose-elongated, open, the pedicels capillary; sheaths naked at the throat; spikelets not unfrequently two-flowered; perennial._

11. S. compressus, Kunth. Very smooth, _leafy to the top; culms tufted, stout, very flat_; sheaths flattened, much longer than the internodes; _leaves erect_, narrow, conduplicate-channelled; empty glumes acutish, about one third shorter than the obtuse flowering one.--Bogs, on Long Island and in the pine-barrens of N. J. Sept.--Forming strong tussocks, 1--2 high. Panicle 8--12' long; spikelets 1” long, purplish.

12. S. serotinus, Gray. Smooth; _culms very slender, flattish_ (8--15'

high), _few-leaved_; leaves very slender, channelled; _panicle soon much exserted_, the diffuse capillary branches scattered; glumes ovate, obtuse, about half the length of the flower.--Sandy wet places, Maine to N. J. and Mich. Sept.--A very delicate gra.s.s; the spikelets half a line long.

29. AGRoSTIS, L. BENT-GRa.s.s. (Pl. 7.)

Spikelets 1-flowered, in an open panicle. Empty glumes somewhat equal, or the lower rather longer, usually longer than the flowering one, pointless. Flowering glume and palet very thin, pointless, naked; the first 3--5-nerved, frequently awned on the back; the palet often minute or none. Stamens chiefly 3. Grain (caryopsis) free.--Culms usually tufted, slender; root commonly perennial. (Name from ?????, _a field_, the place of growth.)

-- 1. AGROSTIS proper. _Palet manifest, but shorter than the glume._

A. aLBA, L. (FIORIN or WHITE BENT-GRa.s.s.) Rootstocks creeping or stoloniferous; culms 1--2 high, often dec.u.mbent at base; leaves short, flat, the ligule long and acute; panicle contracted after flowering, greenish, purplish or brownish, the branches slightly rough; flowering glume nearly equalling the empty ones, 3-nerved, rarely short-awned, the palet about half as long.--Meadows and fields, a valuable gra.s.s; naturalized from Eu. and cultivated, and perhaps native north and westward.

Var. VULGaRIS, Thurb. (RED TOP. HERD'S-GRa.s.s of Penn., etc.) (Pl. 7, fig. 1, 2.) Panicle more or less spreading after flowering; ligule short and truncate. (A. vulgaris, _With._)--Low meadows and pastures; nat.

from Eu. and cultivated, also perhaps indigenous.

1. A. arachnodes, Ell. Culms (1 high) and leaves very slender; panicle open, weak and drooping; glumes nearly equal, roughish on the keel and margins, the flowering glume shorter, with 2 minute bristles at the truncate apex and a long exceedingly delicate awn on the back above the middle; palet minute.--Mo. to Ky., Tenn., and S. Car.

2. A. exarata, Trin. Culms erect, 1--2 high; leaves mostly erect; panicle narrow, crowded, greenish, the rays mostly flower-bearing to the base; spikelets 1--2” long; glumes nearly equal, acute, the flowering ones shorter, sometimes awned above the middle.--Wisc. (_Vasey_) to Sask., and far westward.

-- 2. TRICHDIUM. _Palet abortive, minute, or none._

3. A. elata, Trin. _Culms firm or stout_ (2--3 high); leaves flat (1--2” wide); upper ligules elongated (2--3” long); _spikelets crowded on the branches of the spreading panicle above the middle_ (1” long); flowering glume awnless, slightly shorter than the rather unequal lower ones; the palet wanting.--Swamps, N. J. and southward. Oct.

4. A. perennans, Tuckerm. (THIN-GRa.s.s.) _Culms slender_, erect from a dec.u.mbent base (1--2 high); leaves flat (the upper 4--6' long, 1--2”

wide); _panicle at length diffusely spreading, pale green; the branches short, divided and flower-bearing from or below the middle; flowering glume awnless_ (rarely short-awned), shorter than the unequal lower ones; the palet minute or obsolete.--Damp shaded places. July, Aug.--Spikelets, etc., as in n. 5, into which it seems to vary.

5. A. scabra, Willd. (HAIR-GRa.s.s.) (Pl. 7, fig. 3.) _Culms very slender_, erect (1--2 high); leaves short and narrow, the lower soon involute (the upper 1--3' long, less than 1” wide); _panicle very loose and divergent, purplish, the long capillary branches flower-bearing at and near the apex; flowering glume awnless or occasionally short-awned_ on the back, shorter than the rather unequal very acute empty ones; the palet minute or obsolete; root biennial?--Exsiccated places; common.

June--Aug.--Remarkable for the long and divergent capillary branches of the extremely loose panicle; these are whorled, rough with very minute bristles (under a lens), as also the keel of the glumes. Spikelets 1”

long. A dwarf mountain form occurs, growing in tufts in hollows of rocks, etc.--A variety (?) from about the White Mountains, etc. (var.

montana, _Tuckerm_.), has a more or less exserted awn.

6. A. canna, L. (BROWN BENT-GRa.s.s.) Culms 8'--2 high; root-leaves involute-bristle-form, those of the culm flat and broader; panicle loose; lower glumes slightly unequal, ovate-lanceolate, very acute, the flowering one _exsertly awned on the back_ at or below the middle; spikelets brownish or purplish, rarely pale or greenish (1--1”

long).--Meadows, sparingly naturalized eastward. A mountain form with shorter and more spreading panicle (A. Pickeringii & A. concinna, _Tuckerm_., A. canina, var. alpina, _Oakes_, & Ed. 2, and essentially A.

rubra, _L_. ex _Wahl_., and A. borealis, _Hartm._) is indigenous on mountain-tops, Maine to N. Y.; also an ampler form in the Alleghanies of Penn. and southward (A. rupestris, _Chapman_, etc.). July--Aug. (Eu.)

30. POLYPGON, Desf. BEARD-GRa.s.s. (Pl. 8.)

Spikelets 1-flowered, in a contracted, mostly spike-like panicle. Empty glumes nearly equal, long-awned, much longer than the membranaceous flowering one which is commonly short-awned below the apex. Stamens 3.

Grain free. (Name composed of p???, _much_, and p????, _beard_.)