Part 198 (1/2)

[=] _Spikelets 1--1” long._

11. P. xanthoph?sum, Gray. Culm simple, or at length branched near the base (9--15' high); _sheaths hairy; leaves lanceolate, very acute_ (4--6' long by ' wide), _not dilated at the ciliate-bearded clasping base, smooth_ except the margins, _strongly 9--11-nerved; panicle long-peduncled, very simple_, the appressed branches bearing a few _roundish-obovate spikelets_ (about 1” long); lower glume ovate, acutish, {1/3}-- the length of the 9-nerved second.--Dry sandy soil, Maine to Penn., Wisc., Iowa, and northward; rare.

June.--Yellowish-green; spikelets minutely downy; sterile flower sometimes staminate.

12. P. latiflium, L. Culm (1--2 high) smooth; the joints and the throat or margins of the otherwise _smooth sheaths often bearded with soft woolly hairs; leaves broadly oblong-lanceolate from a heart-clasping base_ (often 1' wide), taper-pointed, 11--15-nerved, smooth, or sparingly downy-hairy; panicle more or less exserted (2--3'

long), usually long-peduncled, the branches spreading; _spikelets obovate, 1” long_, downy; lower glume ovate, not half the length of the many-nerved second; sterile flower often (not always) with 3 stamens.--Moist thickets; common. June--Aug.

13. P. clandestnum, L. (Pl. 13, fig. 6, 7.) Culm rigid (1--3 high), very leafy to the top, at length producing appressed branches, the _joints naked_; _sheaths rough with papillae bearing very stiff and spreading bristly hairs_; leaves oblong-lanceolate from a heart-clasping base, very taper-pointed; lateral and usually also the terminal _panicle more or less enclosed in the sheaths_, or with the terminal one at length long-peduncled;--otherwise resembling n. 12; but _the spikelets more ovoid_, often smooth; the lower flower (always?) neutral.--Low thickets and river-banks, N. Eng. to Mich., Mo., and southward.

June--Sept.

14. P. viscidum, Ell. Culms stout, upright or ascending, at length much branched, leafy to the top, _densely velvety-downy all over_, as also the sheaths, with reflexed soft and often clammy hairs, except a ring below each joint; leaves likewise velvety, lanceolate (' wide), 11--13-nerved; panicle spreading, the lateral ones included; _spikelets obovate_, 1 or 1” _long_, downy; the roundish lower glume scarcely one fourth the length of the 7-nerved second one.--Damp soil, N. J. to Va., and southward. Aug.

15. P. scoparium, Lam. _Culms_ upright, at length much branched and reclining (1--2 long), _roughish; leaves lanceolate_ (3--5' long by {1/3}--' wide), _rather faintly 9-nerved_, hairy or smooth, _fringed_ on the whole margin or next the base _with long and stiff spreading hairs, the sheaths bristly throughout_ with similar hairs; _panicle open, nearly simple, bearing few_ tumid-obovate hairy or smoothish _spikelets about 1” long_; lower glume roundish, about half or a quarter of the length of the upper one. (P. pauciflorum, _Ell._)--Wet meadows and copses, E. Ma.s.s. to Minn., west and southward. June, July.

16. P. commutatum, Schultes. Rather slender, erect, 1--2 high, _nearly glabrous_; leaves lanceolate, ac.u.minate (3--6' long), the margins toward the base and the sheaths spa.r.s.ely ciliate; panicle spreading, often short-peduncled; _spikelets_ scattered, glabrous, _oblong, acutish_, little more than 1” long; _lower glume ovate_, often acute.--N. Y. to Fla.--A frequent variety with smaller spikelets (not 1” long) approaches the next, and has also been confused with P.

dichotomum.--Ont. to Va. and southward.

[=][=] _Spikelets less than 1” long._

17. P. nitidum, Michx. (Lam.?) Resembles the last; leaves rather thick and the princ.i.p.al nerves very obscure or none except at the base; panicle broad, more slender; spikelets smaller ({2/3}” long), broadly ovate and very obtuse; lower glume very obtuse. (P. sphaerocarpon, _Ell._)--N. Y. to Ga., and westward.

18. P. microcarpon, Muhl. Like the last; the broadly lanceolate leaves nearly similar, but usually longer (8' long or less), distinctly nerved; panicle soon exserted on a slender peduncle, rather narrower, with numerous slender branches and very many-flowered (3--7' long); spikelets about ” long, ovoid, smooth or smoothish; lower glume orbicular and very small.--Dry or moist thickets, Penn. to Mich., Neb., and southward. July--Sept.

[++][++] _Culm-leaves linear or sometimes narrowly lanceolate (basal often lanceolate); primary nerves often indistinct or none; spikelets small._

19. P. depauperatum, Muhl. Culms simple or branched from the base, forming close tufts (6--12' high), terminated by a simple and few-flowered contracted panicle, often much overtopped by the narrowly linear and elongated (4--7') upper leaves; spikelets --1” long, oval-obovate, commonly pointed when young; lower glume ovate.--Varies, with the leaves involute, at least when dry (P. involutum, _Torr._), and with the sheaths either beset with long hairs or nearly smooth; the panicle either partly included, or on a long and slender peduncle.--Dry woods and hills; rather common. June.

20. P. consanguineum, Kunth. Culms slender, 1--2 high, often dec.u.mbent and rooting below; nearly glabrous or the sheaths and leaves somewhat p.u.b.escent or villous; panicle small, with rather few spreading few-flowered branches; _spikelets_ 1--1” long, _oblong-obovate, acutish_.--Dry woods, Norfolk, Va., and south to Fl. and Tex.

21. P. dichotomum, L.! Culms (8'--2 high) at first mostly simple, bearing a more or less exserted spreading compound panicle (1--3' long), and linear to linear-lanceolate flat leaves (those tufted at the root usually ovate-lanceolate and very short, thickish); but commonly branching later in the season, the branches often cl.u.s.tered, and bearing nearly simple and included small panicles; _spikelets_ --{2/3}” long, _elliptical, obtuse_, downy or smooth; lower glume roundish.--Common everywhere. Very variable both in habit and in the amount of villosity (depending upon the soil, exposure, season, etc.), so that it is difficult to specify any well defined varieties. The more conspicuous forms are (_a_) _commune_, with simple culms erect or ascending, and leaves suberect, usually pale green--(_b_) _fasciculatum_, with cl.u.s.tered leafy branches and short peduncles, a common autumnal state--and (_c_) _gracile_, the culms lax, very slender and elongated, with rather distant spreading leaves (usually bright green), and mostly long-pedunculate panicles.

22. P. laxiflrum, Lam.! Closely resembling the last species, in its several forms; distinguished by the larger acutish spikelets (nearly or quite 1” long).--Common.

-- 3. ECHINoCHLOA. _Spikelets imbricated-spiked on the branches of the simple or compound raceme or panicle, usually rough with appressed stiff hairs; lower palet of the sterile flower awl-pointed or awned._

P. CRUS-GaLLI, L. (BARNYARD-GRa.s.s.) Root annual; culms stout, branching from the base (1--4 high); leaves lanceolate (' wide or more), rough-margined, otherwise with the sheaths smooth; spikes alternate (1--3' long), crowded in a dense panicle; glumes ovate, abruptly pointed; glume of the neutral flower bearing a rough awn of variable length.--Varies greatly; sometimes awnless or nearly so; sometimes _long-awned_, especially in the var. HiSPIDUM, a very large and coa.r.s.e form with the sheaths of the leaves very bristly.--Moist, chiefly manured soil; the variety in ditches, especially of brackish water; possibly indigenous. Aug.--Oct. (Nat. from Eu.)

6. SETaRIA, Beauv. BRISTLY FOXTAIL GRa.s.s. (Pl. 13)

Spikelets altogether as in Panic.u.m proper, and awnless, but with the short peduncles bearing below the joint of the spikelet solitary or cl.u.s.tered bristles resembling awns (but not forming an involucre).

Inflorescence a dense spiked panicle, or apparently a cylindrical spike.--Annuals, in cultivated or manured grounds, with linear or lanceolate flat leaves. (Name from _seta_, a bristle.)

[*] _Bristles single or in pairs, roughened or barbed downward._

S. VERTICILLaTA, Beauv. Spike cylindrical (2--3' long, pale green), composed of apparently whorled short cl.u.s.ters; bristles short, adhesive.--Near dwellings. (Adv. from Eu.)