Class II. MONOCOTYLEDONOUS or ENDOGENOUS PLANTS. (continued 3)

[*] Stipules free from the sheathing base of the leaf.

19. P. zosteræfòlius, Schum. Stem branching, wing-fattened; leaves linear and grass-like (commonly 4´ by 1½´´), abruptly pointed, with many fine and 3 larger nerves; stipules (seen young) oblong, very obtuse; spikes cylindrical, 12–15-flowered, not half as long as the peduncle; fruit obliquely obovate, somewhat keeled and with slight teeth on the back, the sides not impressed, the face arching and terminated by the short style; summit of the large embryo lying transverse to the fruit. (P. compressus, Fries; not L.?)—Still and slow-flowing waters, N. Eng. to N. J., Iowa, and Minn. Aug., Sept. (Eu.)

20. P. Híllii, Morong. Stem slender, widely branching, flattish; leaves linear, acute (1–2½´ long by ½–1¼´´ wide), 3-nerved, the lateral nerves delicate and near the margin; stipules whitish, striate, obtuse (3–5´´ long); spikes capitate (3–6-fruited), on short spreading or recurved peduncles; fruit as in the last.—Mich. and western N. Y.

21. P. obtusifòlius, Mertens & Koch. Stem flattened, very branching; leaves linear, tapering toward the base, obtuse and mucronate or very acute, 3- (rarely 5-) nerved; stipules elongated, very obtuse; spike ovate, continuous, 5–8-flowered, about the length of the peduncle; fruit oval, apiculate with the style, not keeled when fresh, upper portion of embryo coiled inward and lying transverse to the fruit.—Slow streams and ponds, Canada and N. Eng. to western N. Y. and Mich. Sept., Oct. (Eu.)

22. P. pauciflòrus, Pursh. Stem filiform, flattish and very branching; leaves narrowly linear (1–2´ long and seldom ½´´ wide), acute, obscurely 3-nerved; stipules obtuse; spikes capitate, 1–4- (usually 2-) flowered, on short club-shaped peduncles; fruit roundish-lenticular; the back more or less crested; upper portion of the embryo incurved in a circle.—Still or stagnant waters, N. Brunswick to Ga., Iowa, Minn., and westward.

Var. Niagarénsis, Gray. Stem often longer (1–3°); leaves larger (1½–3½´ long by 1´´ wide or less), 3–5-nerved at base, very acute and mucronate, narrowed to the subpetiolate base. (P. Niagarensis, Tuckerm.)—Running water, Great Lakes to S. C.; also in Cal.

23. P. pusíllus, L. Stem slender, flattish or nearly cylindrical, often very branching; leaves narrow- or setaceous-linear, acuminate, acute or subacute, 1–3-nerved, furnished with translucent glands on each side at the base; stipules at first obtuse; spikes interrupted or capitate, 2–8-flowered, on rather long peduncles; fruit obliquely elliptical, scarcely keeled; apex of embryo incurved and directed obliquely downward.—Pools and ditches, N. Scotia to N. J., west to Minn. and Mo., and westward.—Leaves sometimes almost setaceous (var. tenuissimus, Koch).

Var. polyphýllus, Morong. Dwarf form (3–5´ high), divaricately branching from the base, very leafy throughout; leaves very obtuse, not cuspidate, 3-nerved; non-flowering but abundantly provided with propagating buds which are formed on the thickened and hardened ends of the branches and closely invested by imbricated leaves.—In a shallow pool, S. Natick, Mass.

24. P. mucronàtus, Schrad. Resembling P. pusillus, but stem less branching; leaves broader (almost 1´´ wide), often 5-nerved; spikes interrupted. (P. pusillus, var. major, Fries.)—N. Brunswick to western N. Y., Mich., and Minn. July. (Eu.)

25. P. gemmíparus, Robbins. Stem filiform, branching, terete, varying greatly in height; leaves hair-like, sometimes not as broad as the stem, often with no apparent midrib, tapering to the finest point (1–3´ long), bi-glandular at base; stipules ½–1´ long; spikes few (3–6-flowered), interrupted, on long filiform peduncles; propagating buds very numerous; fruit like that of P. pusillus, very rare. (P. pusillus, var.? gemmiparus, Robbins.)—Slow-moving streams and still water, Mass. Aug., Sept.

26. P. Tuckermàni, Robbins. Very slender and delicate from a creeping rootstock, of a fine light green; stem filiform with several short and repeatedly dichotomous leaf-bearing branches; leaves thin and flat, but setaceous and tapering to near the fineness of a hair (1–4´ long and {1/3}´´ extreme width), obscurely 1–3-nerved, with a few coarse reticulations; stipules rather persistent below, {1/3}´ long, obtuse; peduncle solitary, very long, rather thickened upward; spike 4–8-flowered, in fruit continuous, oblong; fruit thick-lenticular, obscurely 3-keeled; nutlet slightly impressed on the sides; shell thick and hard; embryo nearly annular.—Cold ponds, White Mountains of N. H., N. Y., and N. J.

[*][*] Stipules united with the sheathing base of the leaf.

27. P. pectinàtus, L. Stem filiform, repeatedly dichotomous; leaves very narrowly linear, attenuate to the apex, 1-nerved with a few transverse veins; spikes interrupted, on long filiform peduncles; fruit obliquely broad-obovate, compressed, bluntly keeled; shell of nutlet very thick; embryo spirally incurved.—N. Brunswick to Fla., westward across the continent. Aug.–Oct. (Eu.)

28. P. marìnus, L. Resembling narrow-leaved forms of the last species, low and very leafy; peduncles much elongated; fruit much smaller (1´´ long) and thinner, round-obovate, not keeled upon the rounded back, tipped with the broad sessile stigma; embryo annular.—Western N. Y., Ill., Mich., and southward. Probably the range of this species is much more extensive than indicated, as it has been confounded with P. pectinatus.

29. P. Robbínsii, Oakes. Stem ascending from a creeping base, rigid, very branching, invested by the bases of the leaves and stipules; leaves crowded in two ranks, recurved-spreading, narrow-lanceolate or linear (3–5´ long and 2–3´´ wide), acuminate, ciliate-serrulate with translucent teeth, many-nerved; stipules obtuse when young, their nerves soon becoming bristles; spikes numerous, loosely few-flowered, on short peduncles; fruit oblong-obovate (2´´ long), keeled with a broadish wing, acutely beaked; embryo stout, ovally annular.—In ponds and slow streams, N. Brunswick to N. J., the N. shore of L. Superior, and far westward.

4. RÚPPIA, L. Ditch-grass.

Flowers perfect, 2 or more approximated on a slender spadix, which is at first enclosed in the sheathing spathe-like base of a leaf, entirely destitute of floral envelopes, consisting of 2 sessile stamens, each with 2 large and separate anther-cells, and 4 small sessile ovaries, with solitary campylotropous suspended ovules; stigma sessile, depressed. Fruit small obliquely ovate pointed drupes, each raised on a slender stalk which appears after flowering; the spadix itself also then raised on an elongated thread-form peduncle. Embryo ovoid, with a short and pointed plumule from the upper end, by the side of the short cotyledon.—Marine herbs, growing under water, with long and thread-like forking stems, and slender almost capillary alternate leaves, sheathing at the base. Flowers rising to the surface at the time of expansion. (Dedicated to H. B. Ruppius, a German botanical author of the early part of the 18th century.)

1. R. marítima, L. Leaves linear-capillary; nut ovate, obliquely erect, 1½´´ long; fruiting peduncles capillary (3–6´ long); stipes 1–12´´ long.—Shallow bays, along the entire coast; also occasionally in saline places in the interior. (Eu., Asia, etc.)

5. ZANNICHÉLLIA, Micheli. Horned Pondweed.

Flowers monœcious, sessile, naked, usually both kinds from the same axil; the sterile consisting of a single stamen, with a slender filament bearing a 2–4-celled anther; the fertile of 2–5 (usually 4) sessile pistils in the same cup-shaped involucre, forming obliquely oblong nutlets in fruit, beaked with a short style, which is tipped by an obliquely disk-shaped or somewhat 2-lobed stigma. Seed orthotropous, suspended, straight. Cotyledon taper, bent and coiled.—Slender branching herbs, growing under water, with mostly opposite long and linear thread-form entire leaves, and sheathing membranous stipules. (Named in honor of Zannichelli, a Venetian botanist.)

1. Z. palústris, L. Style at least half as long as the fruit, which is flattish, somewhat incurved, even, or occasionally more or less toothed on the back (not wing-margined in our plant), nearly sessile; or, in var. pedunculàta, both the cluster and the separate fruits evidently peduncled.—Ponds and slow streams, throughout N. America, but not common. July. (Eu., Asia.)

6. ZOSTÈRA, L. Grass-wrack. Eel-grass.

Flowers monœcious; the two kinds naked and sessile and alternately arranged in two rows on the midrib of one side of a linear leaf-like spadix, which is hidden in a long and sheath-like base of a leaf (spathe); the sterile flowers consisting of single ovate or oval 1-celled sessile anthers, as large as the ovaries, and containing a tuft of threads in place of ordinary pollen; the fertile of single ovate-oblong ovaries attached near their apex, tapering upward into an awl-shaped style, and containing a pendulous orthotropous ovule; stigmas 2, long and bristle-form, deciduous. Utricle bursting irregularly, enclosing an oblong longitudinally ribbed seed (or nutlet). Embryo short and thick (proper cotyledon almost obsolete), with an open chink or cleft its whole length, from which protrudes a doubly curved slender plumule.—Grass-like marine herbs, growing wholly under water, from a jointed creeping stem or rootstock, sheathed by the bases of the very long and linear, obtuse, entire, grass-like, ribbon-shaped leaves (whence the name, from ζωστήρ, a band).

1. Z. marìna, L. Leaves obscurely 3–5-nerved.—Common in shoal water of bays along the coast, from Newf. to Fla. (Eu.)

7. NÀIAS, L. Naiad.

Flowers diœcious or monœcious, axillary, solitary and sessile; the sterile consisting of a single stamen enclosed in a little membranous spathe; anther at first nearly sessile, the filament at length elongated. Fertile flowers consisting of a single ovary tapering into a short style; stigmas 2–4, awl-shaped; ovule erect, anatropous. Fruit a little seed-like nutlet, enclosed in a loose and separable membranous epicarp. Embryo straight, the radicular end downward.—Slender branching herbs, growing under water, with opposite and linear leaves, somewhat crowded into whorls, spinulose-toothed, sessile and dilated at base. Flowers very small, solitary, but often clustered with the branch-leaves in the axils; in summer. (Ναιάς, a water-nymph.)

1. N. marìna, L. Stem rather stout and often armed with broad prickles; leaves broadly linear (3–18´´ long), coarsely and sharply toothed, the dilated base entire; fruit 2–2½´´ long; seed very finely lineate, oblong, slightly compressed. (N. major, All.)—Marshes and salt-springs of western N. Y. and Mich. Teeth of one or more brownish cells upon a many-celled base. (Eu.)

Var. grácilis, Morong. Internodes long (1–3´) and nearly naked, with only a few teeth above; leaves very narrow, the dilated base also toothed; fruit smaller.—Canoga marshes, western N. Y.; also in Fla.

Var. recurvàta, Dudley. Stems short, inclined to be dichotomously branched, recurved-spreading; leaves usually recurved, the teeth prominent, the dilated base with a projecting tooth each side.—Cayuga marshes, N. Y.

2. N. fléxilis, Rostk. & Schmidt. Stems usually very slender; leaves very narrowly linear (½–1´ long), very minutely serrulate; fruit 1½´´ long, narrowly oblong; seeds lance-oval, smooth and shining.—Ponds and slow streams, N. Scotia to S. C., Iowa and Minn. Teeth on the margins of the leaves 1-celled. (Eu.)—Var. robústa, Morong. Stem stout, few-leaved, sparsely branching, elongated; leaves flat, abruptly acute.—E. Mass., Mich., and Tex.

3. N. Índica, Cham., var. gracíllima, A. Br. Branches alternate; leaves very narrowly linear, nearly capillary, straight, serrate, the rounded lobes of the sheathing base spinulose-ciliate; fruit linear, impressed-dotted between the numerous ribs.—Mass. to Penn., west to Ind. and Mo. Teeth of 3 cells each.

Order 127. ERIOCAÙLEÆ. (Pipewort Family.)

Aquatic or marsh herbs, stemless or short-stemmed, with a tuft of fibrous roots, a cluster of linear and often loosely cellular grass-like leaves, and naked scapes sheathed at the base, bearing dense heads of monœcious or rarely diœcious small 2–3-merous flowers, each in the axil of a scarious bract; the perianth double or rarely simple, chaffy; anthers introrse; the fruit a 2–3-celled 2–3-seeded capsule; seeds pendulous, orthotropous; embryo at the apex of mealy albumen.—Chiefly tropical plants, a few in northern temperate regions.

1. Eriocaulon. Perianth double, the inner (corolla) tubular-funnel-form in the staminate flowers; stamens twice as many as its lobes (4). Anthers 2-celled.

2. Pæpalanthus. Perianth as in the last; stamens only as many as the corolla-lobes (3). Anthers 2-celled.

3. Lachnocaulon. Perianth simple, of 3 sepals. Stamens 3, monadelphous below. Anthers 1-celled.

1. ERIOCAÙLON, L. Pipewort.

Flowers monœcious and androgynous, i.e. both kinds in the same head, either intermixed, or the central ones sterile and the exterior fertile, rarely diœcious. Ster. Fl. Calyx of 2 or 3 keeled or boat-shaped sepals, usually spatulate or dilated upward. Corolla tubular, 2–3-lobed, each of the lobes bearing a black gland or spot. Stamens twice as many, one inserted at the base of each lobe and one in each sinus; anthers 2-celled. Pistils rudimentary. Fert. Fl. Calyx as in the sterile flowers, often remote from the rest of the flower (therefore perhaps to be viewed as a pair of bractlets). Corolla of 2 or 3 separate narrow petals. Stamens none. Ovary often stalked, 2–3-lobed, 2–3-celled; style 1; stigmas 2 or 3, slender. Capsule membranaceous, loculicidal.—Leaves mostly smooth, loosely cellular and pellucid, flat or concave above. Scapes or peduncles terminated by a single head, involucrate by some outer empty bracts. Flowers, also the tips of the bracts, etc., usually white-bearded or woolly. (Name compounded of ἔριον, wool, and καυλός, a stalk, from the wool at the base of the scape.)—Our species are all stemless, wholly glabrous excepting at the base and the flowers, with a depressed head and dimerous flowers.

1. E. decangulàre, L. Leaves obtuse, varying from linear-lanceolate to linear-awl-shaped, rather rigid; scapes 10–12-ribbed (1–3° high); head hemispherical, becoming globular (2–7´´ wide); scales of the involucre acutish, straw-color or light brown; chaff (bracts among the flowers) pointed.—Pine-barren swamps, N. J. to Fla. July–Sept.

2. E. gnaphalòdes, Michx. Leaves spreading (2–5´ long), grassy-awl-shaped, rigid, or when submersed thin and pellucid, tapering gradually to a sharp point, mostly shorter than the sheath of the 10-ribbed scape; scales of the involucre very obtuse, turning lead-color; chaff obtuse.—Pine-barren swamps, N. J. to Fla.

3. E. septangulàre, Withering. Leaves short (1–3´ long), awl-shaped, pellucid, soft and very cellular; scape 4–7-striate, slender, 2–6´ high, or when submersed becoming 1–6° long, according to the depth of the water; chaff acutish; head 2–3´´ broad; the bracts, chaff, etc., lead-color, except the white coarse beard.—In ponds or along their borders, Newf. to N. J., west to Ind., Mich., and Minn. July, Aug. (Eu.)

2. PÆPALÁNTHUS, Martius.

Stamens as many as the (often involute) lobes of the funnel-form corolla of the sterile flowers, and opposite them, commonly 3, and the flower ternary throughout. Otherwise nearly as in Eriocaulon. (Name from παιπάλη, dust or flour, and ἄνθος, flower, from the meal-like down or scurf of the heads and flowers of many South American species.)

1. P. flavídulus, Kunth. Tufted, stemless; leaves bristle-awl-shaped (1´ long); scapes very slender, simple, minutely pubescent (6–12´ high), 5-angled; bracts of the involucre oblong, pale straw-color, those among the flowers mostly obsolete; perianth glabrous; sepals and petals of the fertile flowers linear-lanceolate, scarious-white.—Low pine-barrens, S. Va. to Fla.

3. LACHNOCAÙLON, Kunth. Hairy Pipewort.

Flowers monœcious, etc., as in Eriocaulon. Calyx of 3 sepals. Corolla none! Ster. Fl. Stamens 3; filaments below coalescent into a club-shaped tube around the rudiment of a pistil, above separate and elongated; anthers 1-celled! Fert. Fl. Ovary 3-celled, surrounded by 3 tufts of hairs (in place of a corolla). Stigmas 3, two-cleft.—Leaves linear-sword-shaped, tufted. Scape slender, bearing a single head, 2–3-angled, hairy. (Name from λάχνος, wool, and καυλός, stalk.)

1. L. Michaùxii, Kunth.—Low pine-barrens, Va. to Fla.

Order 128. CYPERÀCEÆ. (Sedge Family.)

Grass-like or rush-like herbs, with fibrous roots, mostly solid stems (culms), closed sheaths, and spiked chiefly 3-androus flowers, one in the axil of each of the glume-like imbricated bracts (scales, glumes), destitute of any perianth, or with hypogynous bristles or scales in its place; the 1-celled ovary with a single erect anatropous ovule, in fruit forming an achene. Style 2-cleft with the fruit flattened or lenticular; or 3-cleft and fruit 3-angular. Embryo minute at the base of the somewhat floury albumen. Stem-leaves when present 3-ranked.—A large, widely diffused family.

I. Flowers all perfect, rarely some of them with stamens or pistal abortive; spikes all of one sort.

Tribe I. SCIRPEÆ. Spikelets mostly many-flowered, with only 1 (rarely 2) of the lower scales empty.

[*] Scales of the spikelet strictly 2-ranked, conduplicate and keeled.

[+] Flowers destitute of bristles and of beak to the achene, inflorescence terminal.

1. Cyperus. Spikelets few–many-flowered, usually elongated or slender.

2. Kyllinga. Spikelets 1-flowered (but of 3 or 4 scales), glomerate in a sessile head.

[+][+] Flower furnished with bristles; achene beaked; inflorescence axillary.

3. Dulichium. Spikelets 6–10-flowered, slender, clustered on an axillary peduncle.

[*][*] Scales of the several–many-flowered spikelet imbricated all round (subdistichous in n. 5).

[+] Achene crowned with the bulbous persistent base of the style (usually deciduous in n. 7); flowers without inner scales (bractlets).

[++] Hypogynous bristles (perianth) generally present; culm naked.

4. Eleocharis. Spikelets solitary, terminating the culm. Stamens 3.

[++][++] Bristles always none; culm leafy.

5. Dichromena. Spikelets crowded into a leafy-involucrate head, laterally flattened, the scales more or less conduplicate and keeled. Many of the flowers imperfect or abortive.

6. Psilocarya. Spikelets in broad open cymes. Style almost wholly persistent.

7. Fimbristylis. Spikelets in an involucrate umbel. Culm leafy at base. Style usually wholly deciduous.

[+][+] Style not bulbous at base.

[++] Flowers without inner scales, but bristles generally present.

8. Scirpus. Spikelets solitary or clustered, or in a compound umbel, the stem often leafy at base and inflorescence involucrate. Barbed bristles 3–8 or none. Stamens mostly 3.

9. Eriophorum. As Scirpus, but the bristles naked, exserted and often silky in fruit. Stamens 1–3.

[++][++] Flower with one or more inner scales.

10. Fuirena. Scales of the spikelet awned below the apex. Flower surrounded by 3 stalked petal-like scales alternating with 3 bristles.

11. Hemicarpha. Flower with a single very minute hyaline scale next the axis of the spikelet; bristles none.

12. Lipocarpha. Flower enclosed by 2 inner scales, one next the axis, the other in front of the achene; bristles none.

Tribe II. RHYNCHOSPOREÆ. Spikelets mostly 1–2-flowered, with 2–many of the lower scales empty.

13. Rhynchospora. Spikelets terete or flattish; scales convex, either loosely enwrapping or regularly imbricated. Achene crowned with a persistent tubercle or beak, and commonly surrounded by bristles.

14. Cladium. Spikelets terete, few-flowered, the scales, etc., as in the preceding. Achene destitute of tubercle. No bristles.

II. Flowers unisexual.

Tribe III. SCLERIEÆ. Flowers monœcious; the staminate and pistillate in the same or in different clustered spikes. Achene naked, bony or crustaceous, supported on a hardened disk.

15. Sclerlia. Spikes few-flowered; lower scales empty. No bristles or inner scales.

Tribe IV. CARICEÆ. Flowers monœcious in the same (androgynous) or in separate spikes or sometimes diœcious. Achene enclosed in a sac (perigynium).

16. Carex. Hypogynous bristle short and enclosed in the perigynium or none.

1. CYPÈRUS, Tourn. Galingale. (Pl. 1.)

Spikelets many–few-flowered, mostly flat, variously arranged, mostly in clusters or heads, which are commonly disposed in a simple or compound terminal umbel. Scales 2-ranked, conduplicate and keeled (their decurrent base below often forming margins or wings to the hollow of the joint of the axis next below), deciduous when old. Stamens 1–3. No bristles or inner scales. Style 2–3-cleft, deciduous. Achene lenticular or triangular, naked at the apex.—Culms mostly triangular, simple, leafy at base, and with one or more leaves at the summit, forming an involucre to the umbel or head. Peduncles or rays unequal, sheathed at base. All flowering in late summer or autumn. (Κύπειρος, the ancient name.)

§ 1. PYCRÈUS. Achene lenticular, the edge turned to the rhachis; spikelet flattened, many flowered; rhachis narrow, not winged. Annuals.

[*] Umbel simple or capitate, rarely slightly compound.

1. C. flavéscens, L. Culms 4–10´ high, spikelets 5–8´´ long; involucre 3-leaved, very unequal; spikelets becoming linear, obtuse, clustered on the 2–4 very short rays (peduncles); scales obtuse, straw-yellow; stamens 3; achene shining, orbicular, its superficial cells oblong.—Low grounds, N. Eng. to Mich., Ill., and southward. (Eu., etc.)

2. C. diándrus, Torr. (Pl. 1, fig. 1–4.) Spikelets lance-oblong (3–9´´), scattered or clustered on the 2–5 very short or unequal rays; scales rather obtuse, purple-brown on the margins or nearly all over; stamens 2, or sometimes 3; achene dull, oblong-obovate; otherwise much like the last.—Low grounds, common from the Atlantic to Minn., Ark., and N. Mex.—Var. castàneus, Torr. Scales more firm and browner; with the type.

3. C. Nuttàllii, Torr. Culms 4–12´ high; spikelets lance-linear, acute and very flat (½–1´ long), crowded on the few usually very short (or some of them distinct) rays; scales oblong, yellowish-brown, rather loose; stamens 2; achene oblong-obovate, very blunt, dull.—Mostly in salt or brackish marshes, along the coast from Mass. to the Gulf.

4. C. polystàchyus, Rottb., var. leptostàchyus, Boeckl. Culms very slender, 6–15´ high; leaves and elongated involucre very narrow; spikelets few to many on the 4–8 rays, linear, acute, 2–9´´ long; scales thin, ovate, acute, closely imbricated, pale brown; stamens 2; achene linear-oblong or clavate, short-pointed, grayish and minutely pitted. (C. microdontus, Torr.)—Margins of ponds and streams, Va. to Fla. and Tex.

[*][*] Umbel compound.

5. C. flavícomus, Vahl. Culm stout (1–3° high); leaves of the involucre 3–5, very long; spikelets linear (4–9´´ long), spiked and crowded on the whole length of the branches of the several-rayed umbel, spreading; scales oval, very obtuse, yellowish and brownish, broadly scarious- (whitish-) margined; stamens 3; achene obovate, mucronate, blackish.—Low grounds, Va. to Fla.

§ 2. CYPERUS proper. Achene triangular; spikelets usually many-flowered, more or less flattened, with carinate scales, the rhachis marginless or nearly so (winged in n. 12).

[*] Stamen 1; spikelets short and small (1½–5´´ long) in globular heads, ovate or linear-oblong, many-flowered; achene oblong-obovate to linear.

[+] Low annuals; involucre 2–3-leaved; heads few; scales pointed.

6. C. aristàtus, Rottb. Dwarf (1–5´ high); spikelets chestnut-brown, oblong becoming linear, 7–13-flowered, in 1–5 ovate heads (sessile and clustered, or short-peduncled); scales nerved, tapering to a long recurved point; achene oblong-obovate, obtuse. (C. inflexus, Muhl.)—Sandy wet shores; common. Sweet-scented in drying.

7. C. acuminàtus, Torr. Slender (3–12´ high); spikelets ovate, becoming oblong, 16–30-flowered, pale; scales obscurely 3-nerved, short-tipped; achene oblong, pointed at both ends.—Low ground, Ill. and southwestward.

[+][+] Tall perennial (1–4° high); heads many, greenish; scales pointless.

8. C. calcaràtus, Nees. Culm obtusely triangular; leaves and involucre very long, keeled; umbel compound, many-rayed; spikelets ovate (1½´´ long), in numerous small heads; achenes pale, linear, on a slender stipe; scales narrow, acutish, obscurely 3-nerved. (C. virens, Gray, in part; not Michx. C. Luzulæ, var. umbellatus, Britt.)—Wet places, Del. to Fla. and Tex.

[*][*] Stamens 3 (2 in C. fuscus); spikelets clustered on the rays of a simple umbel (or in a single sessile head); scales mostly green or greenish and many-nerved, abruptly sharp-pointed; achene obovate, sharply triangular.

[+] Low annuals.

9. C. Compréssus, L. Culms 3–9´ high, with a simple sessile or a few umbellate clusters of oblong to linear spikelets (15–30-flowered and 3–8´´ long) with crowded strongly keeled and very acute pale scales.—Sterile fields along the coast, Md. to Fla. and Tex.; also adventive near Philadelphia.

C. fúscus, L. Of similar habit; spikelets much smaller (2–4´´ long), the thin brown scales (greenish only on the keel) barely acutish and very faintly nerved.—Revere Beach, Mass. (Young); on ballast at Philadelphia. (Adv. from Eu.)

[+][+] Perennial, propagating from hard clustered corms or bulb-like tubers.

10. C. Schweinítzii, Torr. Culm rough on the angles (1–2° high); umbel 4–8-rayed, rays very unequal, erect; spikelets loosely or somewhat remotely 6–12-flowered, with convex many-nerved scales; joints narrowly winged.—Dry sandy shores and ridges, western N. Y. and Penn. to Minn. and Kan.

11. C. filicúlmis, Vahl. Culm slender, wiry, often reclined (8–15´ high); leaves linear (½–2´´ wide) or filiform; spikelets numerous and clustered in one sessile dense head, or in 1–7 additional looser heads on spreading rays of an irregular umbel; joints of the axis naked; scales blunt, greenish.—Dry sterile soil; common, especially southward.

12. C. Gràyii, Torr. Culm thread-form, wiry (6–12´ high); leaves almost bristle-shaped, channelled; umbel simple, 4–6-rayed; spikes 5–10 in a loose head, spreading; joints of the axis winged; scales rather obtuse, greenish-chestnut-color.—Barren sands, Plymouth, Mass., to N. J., near the coast.

§ 3. PAPỲRUS. Style 3-cleft; achene triangular; stamens 3; spikelets many-flowered, flattened, the carinate scales decurrent upon the rhachis as scarious wings; spikes in simple or compound umbels.

[*] Wings of the rhachis soon separating to the base as a pair of free scales; annual.

13. C. erythrorhìzos, Muhl. (Pl. 1, fig. 5–8.) Culm obtusely triangular (3´–3° high); umbel many-rayed; involucre 4–5-leaved, very long; involucels bristle-form; spikelets very numerous, crowded in oblong or cylindrical nearly sessile heads or spikes, spreading horizontally, linear, flattish (3–6´´ long), bright chestnut-colored; scales lanceolate, mucronulate.—Alluvial banks, L. I. to Penn., Mich., Minn., and southward; also adventive in N. Eng.

[*][*] Wings of the rhachis persistently attached; perennial by slender running rootstocks.

[+] Achene round-obovate; scales mucronate or acute, free or spreading.

14. C. Háspan, L. Culms sharply angled (1–1½° high); leaves linear, often reduced to membranous sheaths; umbel spreading, the filiform rays mostly longer than the 2-leaved involucre; spikelets narrowly linear; scales light reddish-brown, oblong, mucronate, 3-nerved.—Ponds and ditches, Va. to Fla. and Tex.

15. C. dentàtus, Torr. (Pl. 1, fig. 9.) Culms slender (1° high); leaves rigid and keeled; umbel erect, shorter than the 3–4-leaved involucre; scales reddish-brown, with green keel, ovate, acute, 7-nerved.—Sandy swamps, N. Eng. and northern N. Y. to S. C. and W. Va. Spikes often abortive and changed into leafy tufts.

[+][+] Achene linear to oblong; scales appressed, pointless or nearly so.

[++] Perennial by tuberiferous stolons.

16. C. rotúndus, L. (Nut-grass.) Culm slender (½–1½° high), longer than the leaves; umbel simple or slightly compound, about equalling the involucre; the few rays each bearing 4–9 dark chestnut-purple 12–40-flowered acute spikelets (4–9´´ long); scales ovate, closely appressed, nerveless except on the keel.—Sandy fields, Va. to Fla. and Tex.; also adventive near Philadelphia and New York city. (Eu.)

17. C. esculéntus, L. Culm (1–2½° high) equalling the leaves; umbel often compound, 4–7-rayed, much shorter than the long involucre; spikelets numerous, light chestnut or straw-color, acutish, 12–30-flowered (4–7´´ long); scales ovate or ovate-oblong narrowly scarious-margined, nerved, the acutish tips rather loose; achene oblong-obovate. (C. phymatodes, Muhl.)—Low grounds, along rivers, etc., N. Brunswick to Fla., west to Minn, and Tex.; spreading extensively by its small nut-like tubers and becoming a pest in cultivated grounds.

[++][++] Perennial, propagating by corm-like tubers from the base; spikelets narrow, acuminate, often teretish; scales oblong-lanceolate; achene linear-oblong.

18. C. strigòsus, L. Culm mostly stout (1–3° high); most of the rays of the umbel elongated (1–5´), their sheaths 2-bristled; spikelets 5–25-flowered, spreading; scales several-nerved, much longer than the achene.—Damp or fertile soil, Canada to Fla., west to Minn., Tex., and the Pacific. Very variable in the number and length of the rays of the simple or compound umbel, and in the size of the spikelets (2½–6 or even 12´´ long), more or less densely crowded on the axis.

§ 4. DICLÍDIUM. Style 3-cleft; spikelets narrow, terete or nearly so, few–many-flowered, the scales closely appressed and the broad wings of the jointed rhachis enclosing the triangular achene.

19. C. speciòsus, Vahl. Culm stout, mostly low (5–20´ high); rays of the simple or compound umbel mostly all short and crowded; spikelets 10–20-flowered, yellowish-brown at maturity (3–7´´ long), the short joints of its axis winged with very broad scaly margins which embrace the ovate triangular achene; the scales ovate, obtusish, imbricately overlapping. (C. Michauxianus, Gray, Manual; not Schultes.)—Low grounds and sandy banks, N. Eng. to Fla., west to Minn. and Tex.

20. C. Engelmánni, Steud. Resembles n. 19; but the spikelets more slender and terete, somewhat remotely 5–15-flowered, the zigzag joints of the axis slender and narrowly winged, and the oblong or oval broadly scarious scales proportionally shorter, so as to expose a part of the axis of each joint, the successive scales not reaching the base of the one above on the same side; achene oblong-linear, very small.—Low grounds, Mass. to Wisc. and southward.

§ 5. MARÍSCUS. Spikelets 1–4-flowered, subterete, usually in dense heads; scales oppressed, several-nerved, the lower empty and often persistent after the fall of the rest of the spikelet; joints of the rhachis winged, enclosing the triangular achene. Perennial.

[*] Spikelets slender and acuminate, more or less refracted in usually close umbelled spikes.—Connecting with § 4.

21. C. Lancastriénsis, Porter. Culm (1–2° high) triangular; leaves rather broadly linear; umbel of 6–9 mostly elongated rays; spikelets very numerous in short-oblong close heads, soon reflexed, of 3–6 narrow scales, the upper and lower empty, twice the length of the linear-oblong achene, which is nearly 1´´ long.—Rich soil, Penn. and N. J. to Ala.

22. C. retrofráctus, Torr. Culm and leaves usually minutely downy and rough on the obtusish angles (1–3° high); umbel many-rayed; spikelets slender-awl-shaped, very numerous in obovate or oblong heads terminating the elongated rays, soon strongly reflexed, 1–2-flowered in the middle (3–5´´ long); scales usually 4 or 5, the two lowest ovate and empty, the fertile lanceolate and pointed, the uppermost involute-awl-shaped; achene linear, 1¼´´ long.—Sandy fields, N. J. to Fla. and Tex.

23. C. refráctus, Engelm. Culm 1–2° high; rays usually more or less elongated; spikelets very slender, in rather loose heads, divaricate or more or less reflexed, 2–4-flowered; achene linear, 1¼´´ long.—N. J. to N. C. and Mo.

[*][*] Spikelets very short, blunt, in densely compacted globose or cylindrical heads.

24. C. ovulàris, Torr. Culm sharply triangular (6´–2° high); umbel 1–6-rayed; spikelets (50–100) in a globular head, 3-flowered, oblong, blunt (1½–2´´ long); scales ovate, obtuse, a little longer than the ovate-oblong achene.—Sandy dry soil, southern N. Y. to Fla., west to Ill., Ark., and Tex.—Var. robústus, Boeckl., is a form with large heads (4–8´´ long), the spikelets 3–4-flowered. (C. Wolfii, Wood.)—Ill. to Ark., and southward.

25. C. Torrèyi, Britton. Like the last, but the heads cylindrical or oblong, spikelets usually 2-flowered, and achene linear-oblong.—L. Island to Fla., west to Tex.

2. KYLLÍNGA, Rottboell. (Pl. 1.)

Spikelets of 3 or 4 two-ranked scales, 1–1½-flowered; the 2 lower scales minute and empty, as in Cyperus, § 4, but style oftener 2-cleft and achene lenticular; spikes densely aggregated in solitary or triple sessile heads.—Culms leafy at base; involucre 3-leaved. (Named after Peter Kylling, a Danish botanist of the 17th century.)

1. K. pùmila, Michx. Annual; culms 2–9´ high; head globular or 3-lobed, whitish-green (about 4´´ broad), spikelets strictly 1-flowered; upper scales ovate, pointed, rough on the keel; stamens and styles 2; leaves linear.—Low grounds, Ohio to Ill., south to Fla. and Tex. Aug.

3. DULÍCHIUM, Pers. (Pl. 1.)

Spikelets many- (6–10-) flowered, linear, flattened, sessile in 2 ranks on axillary solitary peduncles emerging from the sheaths of the leaves; scales 2-ranked, lanceolate, decurrent, forming flat wing-like margins on the joint below. Perianth of 6–9 downwardly barbed bristles. Stamens 3. Style 2-cleft above. Achene flattened, linear-oblong, beaked with the long persistent style.—A perennial herb, with a terete simple hollow culm (1–2° high), jointed and leafy to the summit; leaves short and flat, linear, 3-ranked. (An alteration of Dulcichinum, an old name for a species of Cyperus.)

1. D. spathàceum, Pers.—Borders of ponds, N. Scotia to Fla., west to Minn. and Tex. July–Sept.

4. ELEÓCHARIS, R. Br. Spike-Rush. (Pl. 3.)

Spikelet single, terminating the naked culm, many–several-flowered. Scales imbricated all round in many (rarely in 2 or 3) ranks. Perianth of 3–12 (commonly 6) bristles, usually rough or barbed downward, rarely obsolete. Stamens 2–3. Style 2–3-cleft, its bulbous base persistent as a tubercle jointed upon the apex of the lenticular or triangular achene.—Leafless, chiefly perennial, with tufted culms sheathed at the base, from matted or creeping root-stocks; flowering in summer. (Name from ἕλος, a marsh, and χαίρω to delight in; being marsh plants.)

§ 1. Spikelet terete, hardly if at all thicker than the spongy-cellular culm; scales firmly persistent; style mostly 3-cleft; bristles 6 (rarely 7), firm or rigid, mostly barbed downward, equalling or surpassing the triangular or lenticular achene.

[*] Spikelet linear or lanceolate-awl-shaped, few-flowered; scales (only 3–9) few-ranked, convolute-clasping the long flattened joints of the axis, lanceolate, herbaceous (green) and several-nerved on the back, and with thin scarious margins.

1. E. Robbínsii, Oakes. Flower-bearing culms exactly triangular, rather stout, erect (8´–2° high), also producing tufts of capillary abortive stems or fine leaves, which float in the water; sheath obliquely truncate; spikelet 4–10´´ long; achene oblong-obovate, triangular, minutely reticulated, about half the length of the bristles, tipped with a flattened awl-shaped tubercle.—Shallow water, N. Eng. to Fla.

[*][*] Spikelet cylindrical, many-flowered, 1–2´ long; scales in several ranks, firm-coriaceous with scarious margin, pale, nerveless or faintly striate; culms large and stout (2–4° high); basal sheaths often leaf-bearing.

2. E. equisetoìdes, Torr. Culm terete, knotted as if jointed by many cross-partitions; achene smooth (the minute reticulation transversely linear-rectangular), with a conical-beaked tubercle.—Shallow water, R. I. to Fla., west to Mich. and Tex.

3. E. quadrangulàta, R. Br. (Pl. 3, fig. 6–9.) Culm continuous and sharply 4-angled; achene finely reticulated, with a conical flattened distinct tubercle.—Shallow water, central N. Y. to Mich., and southward; rare.

§ 2. Spikelet terete and turgid-ovate, much thicker than the very slender culm; scales thin-coriaceous or firm-membranaceous, persistent, ovate; style 3-cleft; bristles stout, barbed downward (or sometimes upward), as long as the striate and pitted-reticulated triangular achene and its tubercle; culms tufted from fibrous roots, 1–2° high.

4. E. tuberculòsa, R. Br. (Pl. 3, fig. 10.) Culms flattish, striate; spikelet 3–6´´ long, many-flowered; tubercle flattish-cap-shaped, as large as the body of the achene.—Wet sandy soil, from Mass. along the coast to Fla.

5. E. tórtilis, Schult. Culms sharply triangular, capillary, twisting when dry; spikelet 2–3´´ long, few-flowered; conical-beaked tubercle much smaller than the achene. (E. simplex, Torr.)—Eastern shore of Md. to Fla.

§ 3. Spikelets terete, much thicker than the culm, many-flowered; scales imbricated in many or more than 3 ranks, thin-membranaceous or scarious, with a thicker midrib, usually brownish or purplish, sometimes deciduous.

[*] Style 2-cleft (often 3-cleft in n. 7 and 10) and the smooth achene lenticular; culms slender or thread-form, terete or compressed.

[+] Annuals; culms tufted, from fibrous roots.

6. E. capitàta, R. Br. Culms terete, ¼–8´ high or more; spikelets ovate to oblong (1–3´´ long), obtuse, 15–40-flowered; scales thickish, round-ovate, obtuse, brown or brownish with green keel and paler margins; stamens 2; achene obovate, black, about equalling the 6–8 bristles, tipped with a flattened or saucer-shaped tubercle. (E. dispar, E. J. Hill.)—In sand or gravel near sloughs, Md. (Canby) to Fla. and Tex.; N. Ind. (Hill). (S. Am., etc.)

7. E. ovàta, R. Br. Culms nearly terete, 8–14´ high; spikelet globose-ovoid to ovate-oblong, obtuse, 1–6´´ long (dull brown); scales very obtuse, densely crowded in many ranks; style 3- (rarely 2-) cleft; achene obovate with narrow base, pale-brownish, shining, shorter than the 6–8 bristles, broader than the short-deltoid, acute and flattened tubercle. (E. obtusa, Schult.)—Muddy places, N. Brunswick to Minn., south and westward. Variable as to the length of its bristles. A low form, with smaller and more narrowly obovate achenes, and the bristles very short or none, is E. diandra, Wright. A dwarf form occurs with very small and few-flowered heads. (Eu.)

8. E. Engelmánni, Steud. Like the last; spikelets usually narrowly cylindrical and acute or acutish, 2–8´´ long; achene broad and truncate, the tubercle covering the summit; bristles not exceeding the achene. (E. obtusa, var. detonsa, Gray.)—Mass. to Penn. and Mo.

[+][+] Perennials, with running rootstocks.

9. E. olivàcea, Torr. (Pl. 2, fig. 1–5.) Culms flattish, grooved, diffusely tufted on slender matted rootstocks (2–4´ high); spikelet ovate, acutish, 20–30-flowered; scales ovate, obtuse, rather loosely imbricated (purple with a green midrib and slightly scarious margins); achene obovate, dull, abruptly beaked with a narrow tubercle, shorter than the 6–8 bristles.—Wet, sandy soil, Mass. to N. C., and western N. Y.

10. E. palsútris, R. Br. Culms nearly terete, striate, 1–5° high; spikelet oblong-lanceolate, pointed, many-flowered; scales ovate-oblong, loosely imbricated, reddish-brown with a broad and translucent whitish margin and a greenish keel, the upper acutish, the lowest rounded and often enlarged; achene rather narrowly obovate, somewhat shining, crowned with a short ovate or ovate-triangular flattened tubercle, shorter than the usually 4 bristles.—Very common, either in water, when it is pretty stout and tall, or in wet grassy grounds, when it is slender and lower. (Eu., Asia.)—Var. glaucéscens, Gray. Culms slender or filiform; tubercle narrower, acute, beak-like, sometimes half as long as the achene. With the type.—Var. cálva, Gray. Bristles none; tubercle short, but narrower than in the type.—Var. vìgens, L. H. Bailey. Culms very stout, rigid; achene more broadly obovoid. Lake Champlain and along the Great Lakes to Minn.

[*][*] Achene triangular or turgid; style 3-cleft.

[+] Bristles at least equalling the smooth achene, downwardly barbed, persistent.

11. E. rostellàta, Torr. Culms flattened and striate-grooved, wiry, erect (1–2½° high), the sterile ones reclining, rooting and proliferous from the apex (1–2° high), the sheath transversely truncate; spikelet spindle-shaped, 12–20-flowered; scales ovate, obtuse (light-brown); achene obovate-triangular, narrowed into the confluent pyramidal tubercle, which is overtopped by the 4–6 bristles.—Marshes, N. Eng. to S. C., west to Mich. and Ky.

12. E. intermèdia, Schultes. Culms capillary, wiry, striate-grooved, densely tufted from fibrous roots, diffusely spreading or reclining (6–12´ long); spikelet oblong-ovate, acutish, loosely 10–20-flowered (2–3´´ long); scales oblong, obtuse, green-keeled, the sides purplish-brown; achene obovoid with a narrowed base, beaked with a slender conical-awl-shaped distinct tubercle, which nearly equals the 6 bristles.—Wet slopes, Penn. to Iowa, north to Canada.

13. E. Torreyàna, Boeckl. Like the preceding, but more capillary and heads smaller (1½–2´´ long), sometimes proliferous, the one or more short new culms from the axil of its lowest scale, which persists as an herbaceous bract; achene very much smaller, with sharper angles and a short conical tubercle, which is hardly equalled by the 3–6 slender bristles. (E. microcarpa, var. filiculmis, Torr.)—Wet pine-barrens, N. J. to Fla.

(Addendum) 13^a. E. álbida, Torr. Like n. 12 and 13 in habit, somewhat stouter; spikelet dense, ellipsoidal or oblong, 1–4´´ long, acutish, with pale obtuse scales; achene very small, triangular-obovate, very smooth, with a broadly triangular tubercle upon a narrow base, shorter than or exceeding the reddish bristles.—Salt marshes, Northampton Co., Va. (Canby), and south to Fla. and Tex.

[+][+] Bristles 2–4, shorter than the achene, slender and fragile, or none.

14. E. ténuis, Schultes. Culms almost capillary, erect from running rootstocks, 4-angular and flattish (1° high), the sides concave; spikelet elliptical, acutish, 20–30-flowered (3´´ long); scales ovate, obtuse, chestnut-purple with a broad scarious margin and green keel; achene obovate, roughish-wrinkled, crowned with a small depressed tubercle, persistent after the fall of the scales; bristles ½ as long as the achene or none.—N. Scotia to N. C., Minn., and Mo. June.

15. E. compréssa, Sullivant. Culms flat, striate, tufted, erect (1–2° high); spikelet ovate-oblong, or at length lanceolate, 20–30-flowered (4–7´´ long); scales lanceolate-ovate, acute, dark purple with broad white pellucid margins and summit; achene yellowish, obovate-pear-shaped, obtusely triangular, wrinkled, crowned with a small conical and pointed tubercle; bristles 1–4, very slender, fragile, shorter than or equalling the achene (sometimes none or a single rudiment).—Wet places, N. Y. and Ont. to Minn. and Mo.

16. E. melanocárpa, Torr. Culms flattened, grooved, wiry, erect (9–18´ high); spikelet cylindrical-ovoid or oblong, thick, obtuse, densely many-flowered (3–6´´ long); scales closely many-ranked, roundish-ovate, very obtuse, brownish with broad scarious margins; achene smooth, obovate-top-shaped, obtusely triangular, the broad summit entirely covered like a lid by the flat depressed tubercle, which is raised in the centre into a short abrupt triangular point; bristles often obsolete; achene soon blackish.—Wet sand, Mass. to Fla.

17. E. tricostàta, Torr. Culms flattish (1–2° high); spikelet soon cylindrical, densely many-flowered (6–9´´ long), thickish; scales ovate, very obtuse, rusty brown, with broad scarious margins; achene obovate, with 3 prominent thickened angles, minutely rough-wrinkled, crowned with a short-conical acute tubercle; bristles none.—N. J. to Fla.

18. E. Wólfii, Gray. Culms slender (1° high), from very small creeping rhizomes, 2-edged; spikelet ovate-oblong, acute; scales ovate-oblong, obtuse, scarious, pale purple; achene pyriform, shining, with 9 nearly equidistant obtuse ribs and transverse wrinkles between them; tubercle depressed, truncate, more or less apiculate; bristles not seen.—Wet prairies, N. Iowa and S. Minn.

§ 4. Spikelet more or less flattened, thicker than the slender or capillary culm, few–many-flowered; the thin membranaceous scales somewhat 2–3-ranked; style 3-cleft; bristles of the perianth 3–6, fragile or fugacious. Small or delicate species, differing from the last division chiefly in the flattish spikelets.

[*] Tubercle contracted at its junction with the achene.

19. E. aciculàris, R. Br. Culms finely capillary (2–8´ long), more or less 4-angular; spikelet 3–9-flowered; scales ovate-oblong, rather obtuse (greenish with purple sides); achene obovate-oblong, with 3-ribbed angles and 2–3 times as many smaller intermediate ribs, also transversely striate, longer than the 3–4 very fugacious bristles; tubercle conical-triangular.—Muddy shores, across the continent. (Eu., Asia.)

20. E. pygmæ̀a, Torr. Culms bristle like, flattened and grooved (1–2´ high); spikelet ovate, 3–8-flowered; scales ovate (greenish), the upper rather acute; achene ovoid, acutely triangular, smooth and shining, tipped with a minute tubercle; bristles mostly longer than the fruit, sometimes wanting.—Brackish marshes, from N. Brunswick to Fla.

[*][*] Tubercle continuous with the nutlet and not contracted at base.

21. E. pauciflòra, Link. Culms striate-angled, very slender (3–9´ high), scarcely tufted, on slender running rootstocks, with a short truncate sheath at base; scales of the ovate spikelet evidently 2-ranked, chestnut-brown, pointless, all flower-bearing, the two lower larger; bristles 3–6, about as long as the conspicuously beaked triangular achene. (Scirpus pauciflorus, Lightfoot.)—Wet places, N. Y. to N. Ill. and Minn., north and westward. (Eu., Asia.)

5. DICHRÒMENA, Richard. (Pl. 4.)

Spikelets aggregated in a terminal leafy-involucrate head, more or less compressed, few-flowered, all but 3 or 4 of the flowers usually imperfect or abortive. Scales imbricated somewhat in 2 ranks, more or less conduplicate or boat-shaped, keeled, white or whitish. Stamens 3. Style 2-cleft. Perianth, bristles, etc., none. Achene lenticular, wrinkled transversely, crowned with the persistent and broad tubercled base of the style.—Culms leafy, from creeping perennial rootstocks; the leaves of the involucre mostly white at the base (whence the name, from δίς, double, and χρῶμα, color).

1. D. leucocéphala, Michx. Culm triangular (1–2° high); leaves narrow; those of the involucre 4–7; achene truncate, not margined.—Damp pine-barrens, N. J. to Fla. Aug., Sept.

2. D. latifòlia, Baldwin. (Pl. 4, fig. 1–5.) Culm stouter, nearly terete; leaves broadly linear, those of the involucre 8 or 9, tapering from base to apex; achene round-obovate, faintly wrinkled, the tubercle decurrent on its edges.—Low pine-barrens, Va. to Fla.

6. PSILOCÁRYA, Torr. Bald-rush. (Pl. 4.)

Spikelets ovoid, terete, the numerous scales all alike and regularly imbricated, each with a perfect flower. Perianth (bristles) wholly wanting. Stamens mostly 2. Style 2-cleft, its base or the greater part of it enlarging and hardening to form the beak of the lenticular or tumid more or less wrinkled achene.—Annuals, with leafy culms, the spikelets in terminal and axillary cymes. (Name from ψιλός, naked, and καρύα, nut.)

1. P. scirpoìdes, Torr. Annual (4–10´ high), leafy; leaves flat; spikelets 20–30-flowered; scales oblong-ovate, acute, chestnut-colored; achene somewhat margined, beaked with a sword-shaped almost wholly persistent style. (Rhynchospora scirpoides, Gray.)—Inundated places, S. N. Eng.

7. FIMBRÍSTYLIS, Vahl. (Pl. 3.)

Spikelets several–many-flowered, terete; scales all floriferous, regularly imbricated in several ranks. Perianth (bristles, etc.) none. Stamens 1–3. Style 2–3-cleft, often with a dilated or tumid base, which is deciduous (except in n. 4) from the apex of the naked lenticular or triangular achene. Otherwise as in Scirpus.—Culms leafy at base. Spikelets in our species umbelled, and the involucre 2–3-leaved. (Name compounded of fimbria, a fringe, and stylus, style, which is fringed with hairs in the genuine species.)

[*] Style 2-cleft, flattened and ciliate; achene lenticular; tubercle soon deciduous; spikelets many-flowered.

1. F. spadícea, Vahl, var. castànea, Gray. Culms (1–2½° high) tufted from a perennial root, rigid, as are the thread-form convolute-channelled leaves, smooth; spikelets ovate-oblong becoming cylindrical, dark chestnut-color (2´´ thick); stamens 2 or 3; achene very minutely striate and reticulated.—Salt marshes along the coast, N. Y. and N. J. to Fla. July–Sept.—Scales lighter colored than in the tropical form.

2. F. láxa, Vahl. (Pl. 3, fig. 1–5.) Culms slender (2–12´ high) from an annual root, weak, grooved and flattish; leaves linear, flat, ciliate-denticulate, glaucous, sometimes hairy; spikelets ovate, acute (3´´ long); stamen 1; achene conspicuously 6–8-ribbed on each side, and with finer cross-lines.—Low ground, Penn. to Fla., west to Ill. and La. July–Sept.

[*][*] Style 3-cleft and achene triangular; tubercle soon deciduous; spikelets smaller and fewer-flowered.

3. F. autumnàlis, Roem. & Schult. (Pl. 3, fig. 6–9.) Annual (3–16´ high), in tufts; culms flat, slender, diffuse or erect; leaves flat, acute; umbel compound; spikelets oblong, acute (1–2´´ long), single or 2–3 in a cluster; scales ovate-lanceolate, mucronate; stamens 1–3.—Low grounds, Maine to Fla., west to Ill. and La.

[*][*][*] Style 3-cleft, filiform and not ciliate; achene acutely triangular; tubercle more or less persistent.

4. F. capillàris, Gray. Low annual, densely tufted (3–9´ high); culm and leaves nearly capillary, the latter short; umbel compound or panicled; spikelets (2´´ long) ovoid-oblong; stamens 2; achene minutely wrinkled, very obtuse.—Sandy fields, N. Eng. to Fla., west to Minn., Tex., and the Pacific.

F. Váhlii, Link (F. congesta, Torr.), a diminutive southern species, with long filiform leaves, sessile capitate spikelets, narrow acuminate scales, and the style 2-cleft and not ciliate, has been found in ballast-sand along the northern coast.

8. SCÍRPUS, Tourn. Bulrush or Club-Rush. (Pl. 3.)

Spikelets several–many-flowered, solitary or in a terminal cluster which is subtended by a 1–several-leaved involucre (this when simple often appearing like a continuation of the culm), terete, the scales being regularly imbricated all round in many or several ranks, or rarely somewhat compressed and the fewer scales inclining to be 2-ranked. Flowers to all the scales, or to all but one or two of the lowest, all perfect. Perianth of 3–6 mostly retrorsely barbed or ciliate bristles (not elongated), or sometimes wanting. Stamens mostly 3. Style 2–3-cleft, simple, not bulbous at base, wholly deciduous, or sometimes leaving a tip or point to the lenticular or triangular achene.—Culms sheathed at base; the sheaths usually leaf-bearing. Mostly perennials; flowering in summer. (The Latin name of the Bulrush.)

[*] Spikelets solitary, few-flowered, small, often flattish; achene triangular, smooth.

[+] Involucre a short awl-shaped bract; culms tufted (3–12´ high), filiform.

1. S. cæspitòsus, L. Culms terete, wiry, densely sheathed at base, in compact turfy tufts; the upper sheath bearing a very short awl-shaped leaf; spikelet ovoid, rusty-color; involucral bract a rigid-pointed scale, resembling the lowest proper scale of the spikelet and scarcely surpassing it; bristles 6, smooth, longer than the abruptly short-pointed achene.—Coast of Maine, alpine summits of N. Eng., swamps of northern N. Y., N. Ill., Minn., and northward; also on Roan Mt., N. C. (Eu.)

2. S. Clintònii, Gray. Culms acutely triangular, almost bristle-like; sheaths at the base bearing a very slender almost bristle-shaped leaf shorter (usually very much shorter) than the culm; involucral bract awl-shaped, mostly shorter than the chestnut-colored ovate spikelet, which has pointless scales; otherwise as the next.—Rather dry plains, N. Y. June.

3. S. planifòlius, Muhl. Culms triangular, leafy at base; leaves linear, flat, as long as the culm, and like it rough-edged; involucral bract a bristle-tipped scale usually overtopping the ovate or oblong chestnut-colored spikelet, the green midrib of the scales extended into sharp points; bristles upwardly hairy, as long as the pointless achene.—Dry or moist ground, N. Eng. to Del., west to western N. Y. and Penn.; W. Mo. (B. F. Bush.).

[+][+] One-leaved involucre more conspicuous, and as if continuing the culm.

4. S. subterminàlis, Torr. Aquatic; culms (1–3° long, thickish-filiform) partly and the shorter filiform leaves wholly submersed, cellular; the filiform green bract 6–12´´ long, much surpassing the oblong spikelet; scales somewhat pointed; bristles 6, bearded downward, rather shorter than the abruptly-pointed achene.—Slow streams and ponds, N. Eng. to N. J., west to Mich. and N. Ind.—Var. terréstris, Paine; less tall, with firmer stem and leaves, and fruiting spike more turgid. Growing chiefly emersed; Herkimer Co., N. Y.

[*][*] Spikelets clustered (rarely only one), appearing lateral, the one-leaved involucre resembling and seeming to be a continuation of the naked culm.

[+] Culm sharply triangular, stout, chiefly from running rootstocks; spikelets many-flowered, rusty brown, closely sessile in one cluster; sheaths at base more or less leaf-bearing.

5. S. púngens, Vahl. Running rootstocks long and stout; culm sharply 3-angled throughout (1–4° high) with concave sides; leaves 1–3, elongated (4–10´ long), keeled and channelled; spikelets 1–6, capitate, ovoid, usually long, overtopped by the pointed involucral leaf; scales ovate, sparingly ciliate, 2-cleft at the apex and awn-pointed from between the acute lobes; anthers tipped with an awl-shaped minutely fringed appendage; style 2-cleft (rarely 3-cleft); bristles 2–6, shorter than the obovate plano-convex and mucronate smooth achene.—Borders of salt and fresh ponds and streams, throughout N. Am. (Eu., S. Am.)

6. S. Torrèyi, Olney. Rootstocks slender if any (so that the plant is readily pulled up from the mud); culm 3-angled, with concave sides, rather slender (2–4° high), leafy at base; leaves 2 or 3, more than half the length of the culm, triangular-channelled, slender; spikelets 1–4, oblong or spindle-shaped, acute, distinct, pale chestnut-color, long overtopped by the slender erect involucral leaf; scales ovate, smooth, entire, barely mucronate; style 3-cleft; bristles longer than the unequally triangular-obovate very smooth long-pointed achene.—Borders of ponds, brackish and fresh, N. Eng. to Penn., Mich., and Minn.

7. S. Olnèyi, Gray. Culm 3-wing-angled, with deeply excavated sides, stout (2–7° high), the upper sheath bearing a short triangular leaf or none; spikelets 6–12, closely capitate, ovoid, obtuse, overtopped by the short involucral leaf; scales orbicular, smooth, the inconspicuous mucronate point shorter than the scarious apex; anthers with a very short and blunt minutely bearded tip; style 2-cleft; bristles 6, scarcely equalling the narrowly obovate plano-convex and mucronate achene.—Salt marshes, S. New Eng. to Fla., west to the Pacific.

S. mucronàtus, L. Resembling the last, 1–3° high; spikelets numerous in a dense cluster, oblong-ovate, 6–8´´ long or less; scales ovate, mucronate, firm, scarcely at all scarious; style 3-cleft; achene smaller, broadly obovate.—In a single locality in Delaware Co., Penn.; probably introduced from S. Europe.

[+][+] Culm triangular, tall and stout, from slender running rootstocks; spikelets many-flowered, loosely umbellate or corymbed, involucellate-bracted.

8. S. Cánbyi, Gray. Culm (3–5° high) 3-angled, usually sharply so above, obtusely below, the sheath at base extended into a long slender triangular and channelled leaf (2–4° long); involucral leaf similar (4–8´ long), continuing the culm; spikelets oblong (4–6´´ long), single or sometimes proliferously 2 or 3 together, nodding on the apex of the 5–9 long filiform and flattened peduncles or rays of the dichotomous umbel-like corymb, or the central one nearly sessile; scales loosely imbricated, oblong-ovate, acute, pale, thin and scarious, with a greenish nerved back; bristles 6, firm, furnished above with spreading hairs rather than barbs, equalling the slender abrupt beak of the obovate-triangular shining achene (1½´´ long).—In a pond near Salisbury, Md.

[+][+][+] Culm terete, very tall and stout, from a deep running rootstock, leafless or very nearly so; spikelets numerous, clustered in a one-sided compound umbel-like panicle longer than the involucral leaf; involucellate bracts small, scale-like and rusty-scarious; scales of the spikelets rusty or chestnut-brown, scarious, the midrib extended into a mucronate point.

9. S. lacústris, L. (Great Bulrush.) Culm 3–9° high, ½–1´ thick at base; spikelets ovate-oblong (3–4´´ long); scales mostly a little downy on the back and ciliate; style 2-cleft; achene pale and dull, obovate with a narrowed base, plano-convex, mucronate-pointed, usually overtopped by the 4–6 slender downwardly barbed bristles. (S. validus, Vahl.)—Common everywhere in still fresh water. (Eu., Asia, etc.)

[+][+][+][+] Culms slender from an annual root, terete, plano-convex or obtusely triangular, naked; the sheaths rarely bearing a short leaf; spikelets few or several in a sessile cluster, sometimes solitary, much overtopped by the involucral leaf; bristles often few or wanting.

10. S. débilis, Pursh. (Pl. 3, fig. 1–5.) Culms obtusely triangular, with somewhat hollowed sides, 1–2° high, yellowish-green, shining; spikelets 3–12, capitate, ovate-oblong, obtuse (3–4´´ long), chestnut-brown; involucral leaf often horizontal at maturity; scales roundish; stamens 3; style 2–3-cleft; bristles 6, stout, downwardly barbed, equalling or two surpassing the obovate turgidly plano-convex (or bluntly 3-sided) abruptly mucronate-pointed smoothish achene.—Swamps, Mass. to S. C., Minn. and Neb. Aug., Sept.

11. S. Smíthii, Gray. Culms terete, slender, 3–12´ high, often leaf-bearing from the upper sheath, dull green as are the 1–3 oblong-ovate acute spikelets; involucral leaf always erect; scales oblong-oval; style 2-cleft; bristles 1 or 2 minute rudiments or none; achene somewhat lenticular, smooth, deciduous with the scales.—Wet shores, Delaware Bay to L. Ontario, Mich., N. Ind., and Ill. July.

12. S. supìnus, L., var. Hállii, Gray. Culms filiform, 5–12´ high; upper sheath rarely distinctly leaf-bearing; spikelets 1–7 in a sessile or sometimes geminately proliferous cluster, ovate-oblong becoming cylindrical, greenish; scales ovate, strongly keeled, mucronate-pointed; stamens 2 or 3; style 2-cleft; bristles none; achene obovate-orbicular, mucronate, plano-convex, strongly wrinkled transversely.—Wet shores, Ill. to Tex.; also found in E. Mass. (Hitchings). (Eu.)

[*][*][*] Spikelets in simple or mostly compound umbellate or cymose-panicled clusters, many-flowered, terete; involucre of mostly several flat leaves; culm tall, from tufted or running rootstocks, triangular, leafy, sedge-like; leaves rough on the margin; style mostly 3-cleft.

[+] Spikelets large (6–15´´ long); midrib of the scales extended beyond the mostly lacerate or two-cleft apex into a distinct awn.

13. S. marítimus, L. (Sea Club-Rush.) Leaves flat, linear, as long as the stout culm (1–3° high), those of the involucre 1–4, very unequal; spikelets few–several in a sessile cluster, and often also with 1–4 unequal rays bearing 1–7 ovate or oblong-cylindrical (rusty-brown) spikelets; awns of the scales soon recurved; achene obovate-orbicular, compressed, flat on one side, convex or obtuse-angled on the other, minutely pointed, shining, shorter than the 1–6 unequal and deciduous (sometimes obsolete) bristles.—Saline localities, on the coast from N. Scotia to Fla., and in the interior across the continent. (Eu.)—Var. macrostáchyos, Michx.; larger, with very thick oblong-cylindrical heads (1–1½´ long), and longer involucral leaf (often 1° long).

14. S. fluviátilis, Gray. (River C.) Culm very stout, 3–5° high; leaves flat, broadly linear (½´ wide or more), tapering gradually to a point, the upper and those of the very long involucre very much exceeding the compound umbel; rays 5–9, elongated, recurved-spreading, each bearing 1–5 ovate or oblong-cylindrical acute paler heads; scales less lacerate and awns less recurved; achene obovate, sharply and exactly triangular, conspicuously pointed, opaque, scarcely equalling the 6 rigid bristles.—Borders of lakes and large streams, W. Vt. to Conn. and Penn., west to Minn. and Iowa.

[+][+] Spikelets very numerous, small (1–3´´ long); scales mucronate-pointed or blunt; umbel-like cymose panicle irregular, compound or decompound; culm 2–5° high, unusually leafy; leaves broadly linear, green and rather soft; bristles very slender, often more or less tortuous and naked below.

15. S. sylváticus, L. Spikelets lead-colored, clustered 3–10 together at the end of the mostly slender ultimate divisions of the open decompound panicle, ovoid or lance-ovate, 2´´ long; scales bluntish; bristles 6, downwardly barbed throughout, rather exceeding the triangular short-pointed achene; style 3-cleft.—Along brooks, E. Mass. to N. Y.; rare.

Var. dígynus, Boeckl. Style 2-cleft and the achene not at all angled on the back; stamens 2, and bristles 4. (S. microcarpus, Presl.)—N. Scotia and N. Eng. to Minn., and westward.

16. S. atròvirens, Muhl. Leaves somewhat more rigid; spikelets dull greenish-brown, densely conglomerate (10–30 together) into close heads, these also usually densely clustered in a less compound panicle; scales pointed; bristles sparsely and strongly downwardly barbed above the middle, naked below, nearly straight, as long as the conspicuously pointed and obovate-oblong triangular achene.—Wet meadows and bogs, N. Scotia and N. Eng., west to Minn., Kan., and the Pacific.

17. S. polyphýllus, Vahl. Culm usually more leafy; spikelets yellow-brown, ovate, becoming cylindrical, clustered 3–8 together in small heads on the short ultimate divisions of the open decompound umbel; scales mucronate; bristles 6, usually twice bent, soft-barbed toward the summit only, about twice the length of the achene.—Swamps and borders of ponds, western N. Eng to N. C., west to Minn, and Ark.

9. ERIÓPHORUM, L. Cotton-Grass. (Pl. 3.)

Bristles naked, usually very numerous, often silky and becoming greatly elongated. Otherwise as in Scirpus.—Spikelets single or clustered or umbellate, usually involucrate with erect scale-like bracts, upon a leafy or naked stem; scales membranaceous, 1–3-nerved. Style very slender and elongated, 3-cleft. Achene acutely triangular. (Name composed of ἔριον, wool or cotton, and φορός, bearing.)

[*] Bristles 6, rust-colored, becoming tortuous and entangled; culm very leafy, bearing numerous spikelets in an involucrate decompound cymose-panicled umbel.

1. E. lineàtum, Benth. & Hook. Culm triangular, leafy (1–3° high); leaves linear, flat, rather broad, rough on the margins; umbels terminal and sometimes axillary, loose, drooping, the terminal with a 1–3-leaved involucre much shorter than the long slender rays; spikelets oblong, becoming cylindrical (2–4´´ long), on thread-like drooping pedicels; bristles at maturity scarcely exceeding the ovate green-keeled pointed scales; achene sharp-pointed. (Scirpus lineatus, Michx.)—Low grounds, western N. Eng. to Ga., west to Minn. and Mo.

2. E. cyperìnum, L. (Pl. 3, fig. 6–10, under Scirpus.) (Wool-Grass.) Culm nearly terete (2–5° high); leaves narrowly linear, long, rigid, those of the involucre 3–5, longer than the umbel, the rays at length drooping; spikelets exceedingly numerous, ovate, clustered, or the lateral pedicelled, woolly at maturity (1½–3´´ long); the rust-colored bristles much longer than the pointless scales; achene short-pointed. (Scirpus Eriophorum, Michx.)—Wet meadows and swamps, Newf. to Fla., west to Minn. and Iowa. Exceedingly variable in the character and size of the umbel, the typical form having the spikelets mostly clustered in small heads.—Var. láxum has the spikelets scattered, the lateral long-pedicelled.

[*][*] Bristles 6, crisped, white; spikelet single, small; involucre of one short bract.

3. E. alpìnum, L. (Pl. 3, fig. 1–6.) Culms slender, many in a row from a running rootstock (6–10´ high), scabrous, naked; sheaths at the base awl-tipped.—Cold bogs, Lab. to N. Eng., west to Minn. June. (Eu.)

[*][*][*] Bristles very numerous, not crisped, forming dense cottony heads in fruit.

[+] Culm bearing a single spikelet; involucre none.

4. E. vaginàtum, L. Culms in close tufts (1° high), leafy only at the base, above with 2 inflated leafless sheaths; root-leaves long and thread-form, triangular-channelled; scales of the ovate spikelet long-pointed, lead-color at maturity.—Cold and high peat-bogs, N. Eng. to Penn., Mich., Minn., and northward. May, June. (Eu.)

[+][+] Culm leafy, bearing several umbellate-clustered heads, involucrate.

5. E. Virgínicum, L. Culm rigid (2–4° high); leaves very narrowly linear, elongated, flat; spikelets nearly sessile, crowded in a dense cluster or head; wool rusty or copper-color, only thrice the length of the scale; stamen 1.—Bogs and low meadows, Newf. to Fla., west to Minn. and Neb. July, Aug.—Var. álbum, Gray, has the wool white. N. New York.

6. E. polystáchyon, L. Culm rigid (1–2° high), obscurely triangular; leaves linear, flat, or barely channelled below, triangular at the point; involucre 2–3-leaved; spikelets several (4–12), on smooth nodding peduncles, some of them elongated in fruit; achene obovate; wool white, very straight (1´ long or more).—Bogs, Newf. to Ga., Minn., and westward. June, July. (Eu.)—Var. latifòlium, Gray; peduncles rough; leaves sometimes broader and flatter.

7. E. grácile, Koch. Culm slender (1–2° high), rather triangular; leaves slender, channelled-triangular, rough on the angles; involucre short and scale-like, mostly 1-leaved; peduncles rough or roughish-pubescent; spikelets 3–7, small, when mature the copious white wool 6–9´´ long; achene elliptical-linear.—Cold bogs, Newf. to N. J., west to Minn. and Mo. Scales in our plant mostly light chestnut and about 3-nerved. June–Aug. (Eu.)

10. FUIRÈNA, Rottboell. Umbrella-Grass. (Pl. 2.)

Spikelets many-flowered, terete, clustered or solitary, axillary and terminal. Scales imbricated in many ranks, awned below the apex, all floriferous. Perianth of 3 ovate or heart-shaped petaloid scales, mostly on claws, and usually with as many alternating small bristles. Stamens 3. Style 3-cleft. Achene triangular, pointed with the persistent base of the style. Culms from a perennial root, obtusely triangular. (Named for G. Fuiren, a Danish botanist.)

1. F. squarròsa, Michx., var. híspida, Chapm. (Pl. 2, fig. 1–7.) Stem (1–3° high) leafy; leaves and sheaths usually densely hairy; spikelets ovoid-oblong (4–6´´ long), clustered in heads, bristly with the spreading awns of the scales; perianth-scales rhombic or deltoid-ovate, with a short thick awn or point, the interposed mostly barbed bristles shorter than the achene.—Sandy wet places, N. J. to Fla., west to Ky. and Tex.

Var. pùmila, Torr. Usually low (1–6´ high or more), with 1–6 spikelets; perianth-scales narrowly to broadly oblong or ovate, long-stipitate and attenuate to a long awn; barbed bristles usually exceeding the achene.—Mass. to N. J., Fla., and La.; Mich. The commonest form.

11. HEMICÁRPHA, Nees. (Pl. 2.)

Spikelet, flowers, etc., as in Scirpus, except that there is a minute translucent scale (readily overlooked) between the flower and the axis of the spikelet. Stamen only one. Style 2-cleft. Bristles or other perianth none. (Name from ἥμι, half, and κάρφος, straw or chaff, in allusion to the single inner scalelet.)

1. H. subsquarròsa, Nees. Dwarf or minute annual (1–5´ high); involucre 1-leaved, as if a continuation of the bristle-like culm, and usually with another minute leaf; spikelets 2–3 (barely 2´´ long); scales brown, tipped with a short recurved point.—Sandy borders of ponds and rivers, N. Eng. to Fla., west to the Pacific.

12. LIPOCÁRPHA, R. Br. (Pl. 2.)

Spikelets terete, many-flowered, in a terminal close cluster involucrate by leafy bracts. Scales spatulate, regularly imbricated all round in many ranks, awnless, deciduous, a few of the lowest empty. Inner scales (bractlets) 2 to each flower, thin, one between the scale of the spikelet and the flower, one between the latter and the axis of the spikelet. Bristles or other perianth none. Stamens 1 or 2. Style 2–3-cleft. Achene flattish or triangular, naked at the tip.—Culms leafy at base. (Name formed of λίπος, fat, and κάρφος, chaff, from the thickness of the inner scales of some species.)

1. L. maculàta, Torr. Annual; culm (4–8´ high) much longer than the linear concave leaves; spikelets (1–2´´ long) green and dark-spotted; inner scales delicate; stamen one; achene oblong with a contracted base.—Springy or miry places, Va. to Fla.; near Philadelphia, probably adventive.

13. RHYNCHÓSPORA, Vahl. Beak-Rush. (Pl. 4.)

Spikelets panicled or variously clustered, ovate, globular, or spindle-shaped, terete, or sometimes flattish; but the scales open or barely concave (not boat-shaped nor keeled); the lower commonly loosely imbricated and empty, the uppermost often subtending imperfect flowers. Perianth in the form of bristles (mostly 6). Stamens mostly 3. Achene lenticular, globular, or flat, crowned with a conspicuous tubercle or beak consisting of the persistent indurated base or even of the greater part of the style.—Chiefly perennials, with more or less triangular and leafy culms; the spikelets in terminal and axillary clusters; flowering in summer. (Name composed of ῥύγχος, a snout, and σπορά, a seed, from the beaked achene.)

§ 1. RHYNCHOSPORA proper. Spikelets terete or biconvex, few–many-flowered; style conspicuously 2-cleft, its base only forming the tubercle of the mostly lenticular achene; bristles usually present, merely rough or barbed-denticulate (not plumose).

[*] Achene transversely wrinkled; bristles mostly 6, upwardly denticulate.

1. R. cymòsa, Nutt. Culm triangular; leaves linear (¼´ wide); cymes corymbose, the spikelets crowded and clustered; achene round-obovate, twice the length of the bristles, four times the length of the depressed-conical tubercle.—Low grounds, Penn. and N. J. to Fla., west to N. Ind. and Ill.

2. R. Torreyàna, Gray. (Pl. 4, figs. 1–5.) Culm nearly terete, slender; leaves bristle-form; cymes panicled, somewhat loose, the spikelets mostly pedicelled; achene oblong-obovate, longer than the bristles, thrice the length of the broad compressed-conical tubercle.—Swamps; pine-barrens of N. J. to S. C.

3. R. inexpánsa, Vahl. Culm triangular, slender; leaves narrowly linear; spikelets spindle-shaped, mostly pedicelled, in drooping panicles; achene oblong, half the length of the slender bristles, twice the length of the triangular-subulate tubercle.—Low grounds, Va. to Ga.

[*][*] Achene smooth and even.

[+] Bristles 6, long and conspicuous, upwardly denticulate.

4. R. fúsca, Roem. & Schultes. Culm 6–12´ high; leaves bristle-form channelled; spikelets ovate-oblong, few, clustered in 1–3 loose heads (dark chestnut-color); achene obovate, half the length of the bristles, equalling the triangular-sword-shaped acute tubercle, which is rough serrulate on the margins.—Low grounds, N. Brunswick to N. J., west to L. Superior. (Eu.)

5. R. gracilénta, Gray. Culms very slender, 1–2° high; leaves narrowly linear; spikelets ovoid, in 2–4 small clusters, the lateral long-peduncled; achene ovoid, rather shorter than the bristles, about the length of the flat awl-shaped tubercle.—Low grounds, southern N. Y. and N. J. to Fla.

6. R. oligántha, Gray. Culm and leaves filiform, 6–12´ high; spikelets very few (1–4), ovate-oblong; bristles plumose below the middle; achene obovate-oblong, bearing a conical tubercle {1/3} its length.—Del. (Canby) to Fla.

[+][+] Bristles none, or 1–3 and minute; spikelets pale, 1-flowered.

7. R. pállida, M. A. Curtis. Culm (1–2° high) acutely triangular; leaves and spikelets as in the next species, but only a terminal dense cluster, which is less white or turns pale reddish-tawny; achene obovate-lenticular, tipped with a minute depressed and apiculate tubercle; the delicate bristles 4–5 times shorter or obsolete.—Bogs in pine-barrens of N. J. and N. C.

[+][+][+] Bristles long, denticulate downward, or both ways in n. 11.

[++] Spikelets white or whitish, becoming tawny with age, perfecting only a single flower; stamens usually 2; bristles 9–12, or even 20.

8. R. álba, Vahl. Culm slender (1–2° high), triangular above; leaves narrowly linear or almost bristle-form; spikelets lanceolate, densely crowded in a head-like terminal corymb and usually one or two lateral ones; achene oblong-obovate with a narrowed base, scarcely longer than the flattened-awl-shaped tubercle, shorter than the bristles.—Bogs, Newf. to Fla., west to N. Ind., Minn., and Oregon. (Eu.)

[++][++] Spikelets chestnut-colored or darker in n. 10 and 11, few–several-flowered; stamens 3; bristles usually 6.

9. R. capillàcea, Torr. Culm 6–9´ high, slender; leaves bristle-form; spikelets 3–6 in a terminal cluster, and commonly 1 or 2 on a remote axillary peduncle, oblong-lanceolate (pale chestnut-color, 3´´ long); achene oblong-ovoid, stipitate, very obscurely wrinkled, about half the length of the (6, rarely 12) stout bristles, and twice the length of the lanceolate-beaked tubercle.—Bogs and rocky river-banks, N. Vt. to Penn., west to western N. Y. and Minn.—Var. levisèta, Hill. Bristles perfectly smooth. N. W. Ind.

10. R. Knieskérnii, Carey. Culm 6–18° high, slender; leaves narrowly linear, short; spikelets numerous, crowded in 4–6 distant clusters, oblong-ovate (scarcely 1´´ long); achene obovate, narrowed at base, equalling the bristles, twice the length of the triangular flattened tubercle.—Pine-barrens of N. J. (on bog iron ore exclusively) to Va.; rare.

11. R. glomeràta, Vahl. Culm 1–3° high; leaves linear, flat; spikelets numerous in distant clusters or heads (often in pairs from the same sheath), ovoid-oblong; achene obovate, margined, narrowed at base, as long as the lance-awl-shaped flattened tubercle, which equals the always downwardly barbed bristles.—Low grounds, N. Eng. to Fla., west to Mich. and N. Ind.

12. R. cephalántha, Gray. Culm stout (2–3° high); leaves narrowly linear, flat, keeled; spikelets very numerous, crowded in 2 or 3 or more dense globular heads which are distant (and often in pairs), oblong-lanceolate, dark brown; achene orbicular-obovate, margined, narrowed at base, about as long as the awl-shaped beak; bristles twice longer, stout, barbed downward and sometimes also upward.—Sandy swamps, Long Island to N. J. and Fla.

§ 2. CERATOSCHŒ̀NUS. Spikelets lanceolate, acuminate, in fruit flattish, cymose-panicled, of only one perfect and 1–4 staminate flowers; scales few; bristles rigid, minutely scabrous upward; style simple or barely 2-toothed, filiform and gradually thickened downward, in fruit persistent as an exserted, slender-awl-shaped, upwardly roughened beak, several times longer than the smooth flat obovate achene; coarse perennials; spikelets in flower 4´´, in fruit including the projecting beak about 1´ long.

13. R. corniculàta, Gray. (Horned Rush.) Culm 3–6° high; leaves about 6´´ wide; cymes decompound, diffuse; bristles awl-shaped, stout, unequal, shorter than the achene.—Wet places, Penn. to Fla., west to S. Ind. and Mo.

14. R. macrostàchya, Torr. (Pl. 4, fig. 1–4.) Cymes decompound, or in the northern form somewhat simple and smaller, and the spikelets usually more clustered; bristles capillary, twice the length of the achene.—Borders of ponds, Mass. to N. J. and Fla.; rare.

14. CLÀDIUM, P. Browne. Twig-Rush. (Pl. 5.)

Spikelets ovoid or oblong, of several loosely imbricated scales; the lower empty, one or two above bearing a staminate or imperfect flower; the terminal flower perfect and fertile. Perianth none. Stamens 2. Style 2–3-cleft, deciduous. Achene ovoid or globular, somewhat corky at the summit, or pointed, without any tubercle, in which it differs from Rhynchospora. (Diminutive of κλάδος, a branch, from the repeatedly branched cyme of the original species.)

1. C. mariscoìdes, Torr. Perennial; culm obscurely triangular (1–2° high); leaves narrow, channelled, scarcely rough-margined; cymes small; the spikelets clustered in heads 3–8 together on 2–4 peduncles; style 3-cleft.—Bogs, N. Scotia to Del., west to S. Minn. and Iowa. July.

15. SCLÈRIA, Berg. Nut-Rush. (Pl. 5.)

Flowers monœcious; the fertile spikelets 1-flowered, usually intermixed with clusters of few-flowered staminate spikelets. Scales loosely imbricated, the lower empty. Stamens 1–3. Style 3-cleft. Achene globular, stony, bony, or enamel-like in texture. Bristles, etc., none. Perennials, with triangular leafy culms, mostly from creeping rootstocks; flowering in summer; all in low ground or swamps. Inflorescence, in our species, of terminal and axillary clusters, the lower clusters usually peduncled. (Name, σκληρία, hardness, from the indurated fruit.)

[*] Achene smooth.

1. S. triglomeràta, Michx. Culm (1½–3° high) and broadly linear leaves roughish; fascicles of spikelets few, the lowest peduncled, the upper somewhat in threes; achene ovate-globose or depressed, on an obscure crustaceous disk.—Mass. and Vt. to Fla., west to Minn. and Tex.—Var. grácilis, Britton. Culms slender (1–2° long); fascicles few-flowered, the lower (2–3-flowered) on very long filiform peduncles; achene not more than half as large, acutish.—N. J.

2. S. oligántha, Ell. Culms slender, 2° high, the angles somewhat winged; leaves linear (2´´ wide), smooth except the scabrous apex; lateral fascicles 1 or 2, usually on long exserted peduncles; achene ovate, on a tuberculate disk.—Va. to Fla. and Tex.

[*][*] Achene papillose or warty.

3. S. pauciflòra, Muhl. Smoothish or hairy; culm slender (9–24´ high); leaves narrowly linear; fascicles few-flowered, the lateral pedunculate, sessile, or wanting; bracts ciliate; achene globose-ovate; the disk a narrow ring bearing 3 pairs of minute tubercles.—N. H. to Ohio, south to Fla. and Tex.

[*][*][*] Achene reticulated or wrinkled.

4. S. reticulàris, Michx. (Pl. 5, fig. 6–10.) Culms slender, erect, scabrous (1–2½° high); leaves linear (1–1½´´ wide), smooth; lateral fascicles 1–3, loose, remote, nearly erect, on short often included peduncles; bracts glabrous; achene globose, regularly reticulated and pitted, not hairy, resting upon a double greenish conspicuously 3-lobed disk, the inner appressed to and deciduous with the achene.—E. Mass. to Fla.—Var. pubéscens, Britton. Edges of reticulations more or less hairy, especially toward the apex; lateral fascicles generally on longer peduncles. Pine-barrens of N. J. to Fla.—Var. obscùra, Britton. Achene bony, its surface with very obscure reticulations, nearly smooth at the summit. R. I. and N. C.

5. S. Torreyàna, Walpers. Culms weak, diffuse, slightly scabrous or smooth; leaves linear (2–4´´ wide), smooth; lateral fascicles loose, on more or less elongated and drooping filiform peduncles; achene irregularly pitted-reticulated or pitted-rugose with the ridges somewhat spirally arranged and more or less hairy (sometimes smooth); otherwise as in the last. (S. laxa, Torr.)—Pine-barrens, N. J. to Fla. and Tex.

6. S. verticillàta, Muhl. Smooth; culms simple, slender (4–24´ high); leaves narrowly linear, fascicles 3–9-flowered, 4–6, sessile in an interrupted spikelet; achene globose (½´´ broad), somewhat triangular at base, rough-wrinkled with short elevated ridges; disk obsolete.—E. Mass. to Ont., Minn., and south to the Gulf.

16. CÀREX, Ruppius. Sedge. (By L. H. Bailey.)

Flowers unisexual, destitute of floral envelopes, disposed in spikes; the staminate consisting of three stamens, in the axil of a bract, or scale; the pistillate comprising a single pistil with a bifid or trifid style, forming in fruit a hard lenticular or triangular achene, which is enclosed in a sac (perigynium) formed by the complete union of the borders of a bractlet or of connate bractlets and borne in the axil of a bract, or scale. Staminate and pistillate flowers borne in different parts of the spike (spike androgynous), or in separate spikes on the same culm, or rarely the plant diœcious.—Perennial grass-like herbs with mostly triangular culms, 3-ranked leaves, usually with rough margins and keel, and spikes in the axils of leafy or scale-like bracts, often aggregated into heads. An exceedingly critical genus, the study of which should be attempted only with complete and fully mature specimens. (The classical Latin name, of obscure signification; derived by some from κείρω, to cut, on account of the sharp leaves—as the English name Shear-grass.) (Pl. 5 and 6.)

Synopsis of Sections and Groups.

§ 1. CAREX proper. Staminate flowers forming one or more terminal linear or club-shaped spikes (often pistillate at base or apex). Pistillate flowers usually in distinct and simple mostly peduncled spikes. Cross-section of perigynium circular, obtusely angled, or prominently triangular in outline. Style mostly 3-parted and achene triangular or triquetrous.

[*] 1. Physocarpæ. Perigynium mostly straw-colored at maturity, papery in texture, usually more or less inflated, smooth (sometimes hairy in n. 6), nerved, tapering into a beak as long as or longer than the body; spikes few to many, distinct, compactly flowered; stigmas 3 (2 in n. 10).

[+] 1. Paucifloræ. Perigynium greenish, linear-lanceolate or almost needle shaped, not inflated, strongly deflexed at maturity, several times longer than the inconspicuous scale; spike androgynous, the pistillate flowers at base, few.—Sp. 1.

[+] 2. Lupulinæ. Perigynium green or greenish tawny or sometimes yellow, more or less inflated (except in n. 2–4) long, usually very turgid at base, mostly erect or nearly so, very gradually attenuate to a long slenderly toothed beak exceeding the scale; spikes 3 or more, the staminate mostly 1 and stalked, the pistillate often sessile, usually short and thick, often becoming dark colored in drying.—Sp. 2–8.

[+] 3. Vesicariæ. Perigynium smooth and shining, much inflated, at maturity straw-colored or sometimes purple, beaked and conspicuously short toothed (entire in n. 10), usually prominently few nerved, much shorter than in [+] 2; staminate spikes commonly 2 or more; pistillate spikes as a rule long and densely cylindrical.—Sp. 9–16.

[+] 4. Pseudocyperæ. Perigynium less inflated, more conspicuously nerved or even costate, and with more or less setaceous or awned teeth; scale usually awned; spikes mostly nodding or spreading, comose in appearance, greenish, greenish-yellow, or ochroleucous.—Sp. 17–19.

[+] 5. Squarrosæ. Perigynium obconic or obovoid, squarrose in exceedingly dense short spikes.—Sp. 20, 21.

[*] 2. Trachychlænæ. Perigynium mostly thick and hard in texture, often scabrous or hirsute, straight-beaked; pistillate spikes compactly flowered, mostly large, erect or nearly so; staminate spikes 1 or more; stigmas 3. Generally large and coarse.

[+] 1. Shortianæ. Terminal spike androgynous, staminate below; perigynium small, scabrous, nearly beakless, entire.—Sp. 22.

[+] 2. Anomalæ. Terminal spike all staminate; pistillate spikes long and cylindrical, mostly dense; perigynium broad and short, short-beaked, the orifice very slightly notched or entire, mostly granulate.—Sp. 23.

[+] 3. Hirtæ. A heterogeneous group, distinguished from [+] 2 by the longer and more deeply cut beak (slightly toothed in n. 24), and by the hairy perigynium (smooth in n. 25)—Sp. 24–27.

[+] 4. Paludosæ. Staminate spikes 2 or more, long stalked; the pistillate 2–several, usually all peduncled, long and heavy, loose-flowered, erect or nodding; perigynium large, thick in texture, strongly nerved, mostly smooth, usually conspicuously beaked. Coarse species.—Sp. 28, 29.

[*] 3. Microrhynchæ. Parallel with [*] 2; distinguished in general by the much smaller and nearly or entirely beakless and mostly entire-mouthed perigynium, which is much thinner in texture; stigmas 2 or 3. Paludose and alpine species, of various habit, mostly with colored spikes, often in dense tufts or tussocks.

[+] 1. Atratæ. Terminal spike club-shaped and androgynous with the staminate flowers below (very rarely all staminate in n. 32); pistillate spikes mostly short and dark-colored, erect or drooping; stigmas 3.—Sp. 30–32.

[+] 2. Rigidæ. Mostly stiff, with short erect closely flowered spikes, an entirely staminate terminal spike, dark colored scales, and bracts with purple or black auricles at base; stigmas 2 or 3.—Sp. 33.

[+] 3. Acutæ. Mostly larger and more slender, usually paludose, with green or light-colored large and long spikes; stigmas 2 (3 in n. 39). Distinguished from [+] 2 mainly by habit.—Sp. 34–39.

[+] 4. Cryptocarpæ. Large, with nodding or drooping large spikes, their dark scales very long and conspicuous; stigmas 2.—Sp. 40, 41.

[+] 5. Pendulinæ. Distinguished from [+] 4 by the smaller size, smaller spikes, sheathless bracts, and whitish, more or less granulated, nearly pointless perigynium; stigmas 3.—Sp. 42–45.

[*] 4. Hymenochlænæ. Perigynium mostly light green or whitish, usually thin and membranous, often somewhat inflated or loosely investing the achene, commonly smooth and shining (hairy in n. 46, sometimes in n. 47), slender or oblong, attenuate to a distinct or long minutely toothed straight beak (or beakless or nearly so in [+] 1 and n. 55); pistillate spikes several or many, mostly loosely flowered and on filiform nodding or widely spreading peduncles; bracts leaf-like; terminal spike staminate or androgynous; stigmas 3. Mostly rather tall and slender upland species.

[+] 1. Virescentes. Terminal spike pistillate at top; pistillate spikes oblong or cylindrical, dense, erect; perigynium ovate or obovate, nearly or quite beakless, often hairy.—Sp. 46, 47.

[+] 2. Sylvaticæ. Terminal spike all staminate; pistillate spikes mostly long-exserted, slender; perigynium few-nerved, contracted into a cylindrical beak which is longer than the body.—Sp. 48.

[+] 3. Flexiles. Terminal spike all staminate; pistillate spikes rather thick (very small in n. 50), more or less drooping; perigynium beaked, few-nerved or nerveless, tawny or whitish.—Sp. 49, 50.

[+] 4. Debiles. Terminal spike all staminate (occasionally pistillate above in n. 53); pistillate spikes very narrow and slender, long-exserted and nodding, mostly very loosely flowered; perigynium rather small, not turgid, prominently beaked.—Sp. 51–53.

[+] 5. Gracillimæ. Terminal spike pistillate at top; pistillate spikes habitually thicker than in [+] 4; perigynium ovate-oblong, more or less turgid; the beak short or none.—Sp. 54–57.

[+] 6. Griseæ. Terminal spike staminate; perigynium more or less turgid or plump, often glaucous, scarcely beaked, finely striate; spikes erect.—Sp. 58, 59.

[*] 5. Spirostachyæ. Perigynium smooth or minutely granulated or rarely somewhat serrate on the margins, prominently nerved, mostly yellowish, squarrose, mostly beaked (entirely beakless in n. 63), the orifice entire; staminate spike mostly single; pistillate spikes 2–5, short (usually 1´ long or less), yellow or fuscous, compactly flowered; stigmas 3.—Medium-sized species, growing in meadows and grassy swales.

[+] 1. Granulares. Spikes scattered, cylindrical, the lowest long-stalked; bracts erect, long and leafy; sheaths short or nearly obsolete.—Sp. 60, 61.

[+] 2. Extensæ. Spikes mostly approximate or aggregated at the top of the culm (becoming remote in C. extensa), the lowest 1 or 2 subtended by a long and leafy mostly abruptly spreading and nearly or entirely sheathless bract. Terminal spike sometimes androgynous.—Sp. 62.

[+] 3. Pallescentes. Spikes globular or short-oblong, obtuse, sessile or short-peduncled, approximate at the top of the culm; bracts short, leaf-like, sheathless; perigynium entire at the orifice, the beak none or very short and stout.—Sp. 63, 64.

[*] 6. Dactylostachyæ. Perigynium mostly short and triangular, mostly with a short and straight or curved beak, green or greenish, scarcely inflated; scales of the pistillate spikes mostly whitish (sometimes dark-colored in the Digitatæ), often small; staminate spike mostly one; pistillate spikes short (seldom exceeding 1´), commonly rather loosely flowered and slender (spike single and plant diœcious in n. 83); bracts sheathing, the sheaths often conspicuous and colored.—Low and lax or slender species inhabiting meadows and copses.

[+] 1. Oligocarpæ. Slender and narrow-leaved, with leafy bracts and inconspicuous green sheaths; perigynium rounded on the angles, finely many-striate, often somewhat punctulate as in n. 58, to which the group forms a transition.—Sp. 65–67.

[+] 2. Laxifloræ. Slender and more or less broad-leaved, with mostly leafy bracts, green or purple sheaths, and loosely flowered spikes; perigynium mostly conspicuously three-angled, with a more or less curved beak.—Sp. 68–74.

[+] 3. Paniceæ. Mostly stouter and narrow-leaved, with thinner spikes; perigynium often strongly nerved, not conspicuously triangular, often somewhat turgid; bracts and sheaths various.—Sp. 75–78.

[+] 4. Bicolores. Small species with a beakless, more or less round or pyriform perigynium, which is commonly glaucous; terminal spike androgynous or all staminate; stigmas mostly 2.—Sp. 79.

[+] 5. Digitatæ. Low species; sheaths membranaceous or hyaline and colored, either not prolonged into a bract or the bract very short and not foliaceous; perigynium more or less three-angled, often hairy, the beak straight or nearly so.—Sp. 80–83.

[*] 7. Sphæridiophoræ. Perigynium mostly short and rounded, three-angled in the Triquetræ, firm or hard in texture, not inflated, hairy or scabrous, the beak straight and usually bifid; staminate spike one; pistillate spikes short (1´ long or less), usually globular or short-oblong, more or less sessile and approximate or the longer ones radical (spike single in n. 84); bracts sheathless, short, or obsolete; stigmas rarely two.—Low species of dry ground, with leaves all radical.

[+] 1. Scirpinæ. Spike one, unisexual; plant diœcious.—Sp. 84.

[+] 2. Montanæ. Spikes two to several, the lowest occasionally long-peduncled and radical; perigynium rounded, contracted above and below, mostly bearing two prominent ribs, more or less hairy.—Low species of dry soils.—Sp. 85–91.

[+] 3. Triquetræ. Taller; spikes mostly approximate at the top of the culm, oblong or cylindrical; perigynium conspicuously 3-angled.—Sp. 92.

[*] 8. Phyllostachyæ. Perigynium much as in the Montanæ; spike one, staminate above; pistillate flowers few, often remote, usually on a more or less zigzag rhachis; scales prolonged and leaf-like.—Sp. 93–95.

[*] 9. Leptocephalæ. Perigynium thin in texture, green, oblong or lanceolate or linear in general outline, beakless; spike one, staminate above, thin and slender; stigmas mostly three.—Small, slender and grass-like.—Sp. 96.

[*] 10. Physocephalæ. Spike one, globular or short-oblong, staminate at the apex; perigynium straw-colored, paper-like, more or less inflated; stigmas three. Leaves remarkably broad in our species.—Sp. 97.

§ 2. VIGNEA. Staminate flowers few and inconspicuous, borne at the base or apex of the pistillate spikes. Pistillate flowers in short sessile spikes (or spike single in some cases), which are commonly more or less aggregated into heads or even panicled. Perigynium plano-convex. Styles two and achene lenticular.—The spikes, especially the uppermost, usually have contracted bases when the staminate flowers are borne below the pistillate ones, and empty scales at the top when the staminate flowers are borne at the summit.

[*] 11. Acroarrhenæ. Staminate flowers borne at the top of the spikes (or, in the Multifloræ and Arenariæ, spikes often wholly staminate and the plants occasionally diœcious).

[+] 1. Fœtidæ. Spikes tawny or brown, not elongated, very densely aggregated into a continuous globose somewhat chaffy head; perigynium ovate or ovate-lanceolate, nerveless or nearly so, mostly thin in texture.—Sp. 98, 99.

[+] 2. Vulpinæ. Spikes mostly yellow or tawny when mature, densely aggregated or sometimes somewhat scattered below or even panicled; perigynium thick in texture, spongy at base, mostly stipitate, bearing very conspicuous nerves, which converge below and are especially prominent on the outer side.—Sp. 100–102.

[+] 3. Multifloræ. Heads various, mostly loosely flowered, sometimes a panicle, yellow or tawny; spikes short (rarely longer than broad), staminate flowers sometimes occupying whole spikes in the middle or at the apex of the head; perigynium mostly small and short and nearly nerveless, or in some species becoming nearly lanceolate and more or less prominently nerved, firm in texture, usually numerous.—Sp. 103–108.

[+] 4. Arenariæ. Spikes longer than in the last section, linear or nearly so, aggregated into short, almost globose heads; perigynium lanceolate or ovate-lanceolate, mostly larger and more delicate in texture; scales awn-pointed or very acute. Staminate flowers variously situated.—(C. arenaria.)

[+] 5. Muhlenbergianæ. Spikes green or nearly so when mature, aggregated or scattered, never in compound heads; perigynium mostly short-ovate, staminate flowers always at the top of the spike.—Sp. 109–114.

[+] 6. Dioicæ. Spike commonly one, small; plants small and slender, often diœcious.—Sp. 115–117.

[*] 12. Hyparrhenæ. Staminate flowers borne at the base of the spikes (or in n. 124 and 125 variously situated).

[+] 1. Elongatæ. Spikes silvery green or sometimes tawny when mature, distinct, mostly small; perigynium not wing-margined nor conspicuously broadened, mostly nearly flat on the inner surface.—Sp. 118–124.

[+] 2. Ovales. Spikes tawny or dark, rather large, sometimes crowded; perigynium with a more or less thin or winged margin, which is mostly incurved at maturity, rendering the perigynium concave inside.—Sp. 125–132.

[+] 3. Cyperoideæ. Spikes green, oblong, densely crowded into a short head subtended by two or three leafy bracts which are erect and prolonged from six inches to a foot; perigynium linear-lanceolate, scarcely margined.—Sp. 133.

Artificial Key.

Spike 1, staminate at top; scales of pistillate flowers leaf-like Sp. 93–95

Spike 1, scales not leaf-like.

Usually diœcious, stigma 2 115–117

Stigmas 3.—

Perigynium densely hairy 84

Spike staminate at base; perigynia squarrose 21

Spike staminate at top.—

Globose; leaves broad 97

Perigynium nearly linear, beakless 96

Perigynium long, spindle-shaped 1

Spikes several or numerous, sessile, spicate or capitate; stigmas 2.

All in a globose or ovoid uninterrupted head.

All staminate above.—

Usually green at maturity 112, 114

Usually yellow or tawny or brown 98, 99, 104, 105

All staminate below.—

Leafy-bracteate 133

Not leafy-bracteate.—

Green 118–120

Usually tawny or brown 125–132

Some or all of the spikes distinct or the head interrupted.

Staminate and pistillate flowers variously disposed, some of the spikes often unisexual.

Head large and long 108, C. arenaria

Head short or linear 124, 125

Spikes staminate above 100–114

Spikes staminate below 118–133

Spikes usually more or less pedicelled, the wholly or partially staminate spikes uppermost.

Terminal spike (rarely the 2 or 3 uppermost) staminate only at base.

Stigmas 2 34–38, 79

Stigmas 3; spikes erect,

Short and squarrose 20, 21

Not squarrose 22, 30, 32, 46, 47, 54, 79

Stigmas 3; spikes more or less drooping 31, 51–53, 55–57

Terminal spike or spikes staminate.

Stigmas 2.—

Spikes spreading or pendulous 34, 37, 40, 41

Spikes erect or nearly so 9–16, 34–41, 85–91, 79

Stigmas 3; spikes spreading or drooping.

Perigynium prominently 3-angled 68–74

Perigynium large, thin, much inflated 9–16

Perigynium firmer, not inflated.

Beakless 42–45

Beaked or prominently pointed.—

Teeth long, stiff and sharp 17–19

Teeth short and thin, or none 30, 31, 39, 48–53

Stigmas 3; spikes erect or ascending.

Perigynium hairy.—

Spikes very large, globose 6

Spikes very small, sessile or nearly so 81–83, 85–92

Spikes cylindrical, heavy 24–28

Perigynium granular-roughened 23

Perigynium smooth,

Thin and turgid, loosely enclosing the achene.—

Beakless 58, 59

Beaked 5–17

Firm in texture, not inflated,

Long-beaked, deeply toothed 2–4, 26, 28

Less prominently beaked, short-toothed, sharply 3-angled 69–74

Wholly beakless and pointless 58, 59, 63, 78, 79

Very small, black and shining; leaves capillary 80

Culm and leaves thinly pubescent 64

Perigynium more or less pointed or beaked.

Spikes spreading or drooping 51–53, 68–70, 75

Spikes erect 60–62, 65–68, 71–78

[*] 1. Physocárpæ.—[+] 1. Pauciflòræ.

1. C. pauciflòra, Lightf. (Pl. 5, fig. 1–16.) Very slender but erect, 6–18´ high; leaves very narrow, much shorter than the culm; staminate and pistillate flowers 2–5; perigynium at maturity easily detached.—Cold sphagnum swamps, New Eng. to N. Penn. and Minn.; local. (Eu.)

[*] 1.—[+] 2. Lupulìnæ.

[++] Teeth of the perigynium strongly reflexed.

2. C. subulàta, Michx. Green, very slender but erect, 6´–2° high; leaves narrow, somewhat shorter than the culm; bracts leafy, sheathing; pistillate spikes 2–4, scattered, 2–6-flowered; perigynium deflexed.—Deep sphagnum swamps, R. I. to E. Penn., and southward; very local.

[++][++] Teeth erect or spreading.

[=] Whole plant yellowish; perigynium little or not at all inflated.

3. C. Michauxiàna, Boeckl. Slender but stiff and erect, 1–2° high; leaves narrow and firm, shorter than the culm; spikes 2–3, the lowest usually remote and short-peduncled, the remainder aggregated and sessile; staminate spike small, wholly sessile; perigynium not inflated, erect or spreading, twice longer than the blunt scale. (C. rostrata, Michx.)—Bogs and lake-borders, mountains of N. H. and N. Y., and westward to L. Superior; local.

4. C. folliculàta, L. Stout, 2–3° high; leaves very broad and flat, lax; pistillate spikes 3–4, scattered, all but the uppermost prominently peduncled; staminate spike short-peduncled; perigynium larger, inflated, the scale awned and nearly as long.—Cold swamps, New Eng. to N. J. and Penn., and west to Mich.; rather local.

[=][=] Plant green; perigynium much inflated.

5. C. intuméscens, Rudge. Slender, 18–30´ high; leaves narrow, pistillate spikes two, loosely 1–8-flowered, the perigynium erect-spreading, not prominently many-nerved.—Wet pastures and swamps; common.

6. C. Gràyii, Carey. Larger and stouter; leaves broad and flat, 3–4´´ wide; pistillate spikes 1 or 2, the lowest often peduncled, perfectly globular and compactly 12–30-flowered, the perigynium spreading or deflexed and prominently many-nerved.—Meadows and copses, Vt. to Ill., and south to Ga.; rare eastward.—In var. hispídula, Gray, the perigynium is sparsely hispidulous.

7. C. lupulìna, Muhl. Very stout and leafy; leaves rather broad and loose; pistillate spikes 2–6, approximate at the top of the culm, all closely sessile or the lower sometimes short-peduncled, oblong or short-cylindrical, very heavy and densely flowered; staminate spike small and sessile; perigynium large and rather soft, erect or but slightly spreading, giving the spike a hop-like aspect (whence the name). (C. lurida, Bailey.)—Swamps and wet pastures; frequent.

Var. pedunculàta, Dewey. Spikes more or less scattered, some or all prominently peduncled; staminate spike usually conspicuous, often long-peduncled, very variable in size; perigynium more spreading. (C. gigantea, Rudge.)—With the species, but more common.

Var. polystàchya, Schwein. & Torr. Stouter, the leaves very broad (often ½´); bracts broad and far exceeding the culm; pistillate spikes 4–6, all long (3–4´) and cylindrical, more or less short-peduncled, somewhat scattered, becoming yellow; perigynium very large, ascending. (C. lupuliformis, Sartw.)—N. Y. and N. J.; not common.

C. lupulìna × retrórsa, Dudley. Distinguished from C. lupulina by its straw-colored perigynium, which is less inflated and more spreading, standing at nearly right angles to the axis of the spike; scales acute to short-awned, rough. (C. lurida × retrorsa, Bailey).—Ithaca, N. Y. (Dudley), and Lansing, Mich. (Bailey). Resembles n. 16.

8. C. grándis, Bailey. Distinguished from C. lupulina, var. polystachya, by its much more scattered and mostly shorter slim spikes, which are comparatively loosely flowered; perigynium swollen below but very abruptly contracted into a slender beak 3–4 times as long as the body, spreading at right angles or nearly so, never becoming yellow; scales narrow, smooth. (C. gigantea of previous editions.)—Swamps, Ky., Del., and southward; local.

[*] 1.—[+] 3. Vesicàriæ.

[++] Spikes very small, globular or short-oblong.

9. C. oligospérma, Michx. Very slender, but stiff, 18–30´ high; leaves and bracts very narrow, becoming involute; staminate spike single, peduncled; pistillate spikes 1 or 2, sessile or the lowest very short-peduncled, 3–8-flowered; perigynium turgid, short-ovoid, gradually contracted into a very short and minutely toothed beak, prominently few-nerved, yellow, nearly twice longer than the blunt scale.—Deep swamps and borders of lakes, N. Eng. to Penn. and Minn.; frequent.

10. C. miliàris, Michx. Culm very slender but erect, 12–18´ high, smooth, or slightly rough above on the angles; leaves almost filiform, mostly shorter than the culm; staminate spikes 1–2, exceedingly narrow, elevated an inch or two; pistillate spikes 1–3, the upper one sessile and the lowest very short stalked, 9´´ long or less, the lower subtended by a short leafy bract; perigynium very small, broad or round-ovate or ovate-oblong, thin but firm, bearing a nerve on each side but otherwise nerveless or very nearly so, rounded into a very short terete entire or somewhat erose beak; scales brown, lance-ovate, white tipped, about as long as the perigynium. (C. rotundata? of last ed.)—Outlet of Moosehead Lake, Maine, and northward.

Var. màjor, Bailey. Culm much stouter (often over 2° high), thick and very sharply angled; leaves stout and channelled or involute; staminate spikes short-stalked; the pistillate 1–5, darker, mostly longer and larger; scale varying from wholly obtuse to acutish.—Outlet of Moosehead Lake (Porter), and northward.

Var. (?) aùrea, Bailey. Taller and mostly stouter than the type; pistillate spikes one or two, often staminate at top, yellow or stramineous; perigynium longer, gradually produced into a conspicuous and more or less toothed beak, prominently few-nerved, yellow, broader and usually longer than the blunt scale. (C. pulla, and var. miliaris, last ed.)—Outlet of Moosehead Lake (Smith), and northward.

[++][++] Spikes much larger, cylindrical.

[=] Scales all, or all but the very lowest, smooth.

11. C. utriculàta, Boott. Very stout and robust, 3–4° high; leaves broad (4–6´´) and flat, very prominently nodulose, particularly below; spikes 3–4, 3–6´ long, very thick and dense above but usually more or less attenuate below, erect or nearly so, all but the lowest sessile or very short-stalked; perigynium ovate, only moderately inflated, rather abruptly contracted into a short toothed beak, at maturity usually squarrose, rather prominently few-nerved, the upper longer than the sharp scale, the lower shorter than or only equalling the sharper or awned scale. (C. rostrata, Bailey, etc.)—Swamps, everywhere; common. Passes imperceptibly into var. mìnor, Boott, which is distinguished by its much smaller size, spikes 2½´ long or less, smaller perigynium, blunt scales, and narrower and little nodulose leaves. With the type.

12. C. monìle, Tuckerm. Rather slender but erect, 2–3° high, the culm sharply angled and usually rough above; pistillate spikes 2–3, the lowest one or two short-stalked, erect or spreading, 1–3´ long, narrowly cylindrical; perigynium turgid, prominently beaked, about 10-nerved, ascending, longer than the very sharp scale. (C. Vaseyi, Dewey.)—Meadows and swales; common.—In var. monstròsa, Bailey, the plant is very slender throughout, and the terminal spike more or less pistillate, while the remaining spikes are reduced to one or two which are very small and loosely flowered and usually on very long filiform peduncles. E. Mass. (Swan).

13. C. Tuckermàni, Dewey. Differs from the last chiefly in the comparatively shorter (1–2´ long) spikes, which are much thicker (usually ½´ or more); perigynium greatly inflated and very thin and papery, the body broader than long (about 3´´ thick); scale thin and narrow, acute, all but the very lowest less than half the length of the perigynium.—Swamps, W. New Eng. to N. J., and west to Minn.; frequent.

14. C. bullàta, Schkuhr. (Pl. 6, fig. 15–20.) Slender, 1–2° high; culm very sharply and roughly angled, thin but stiff; leaves narrow, rough-edged, stiff; spikes 1 or 2, remote, short and thick (rarely 1½´ long), sessile or the lower short-peduncled, more or less spreading; perigynium turgid but very firm, dull straw colored and shining as if varnished, prominently few-nerved, the long beak usually minutely roughened; scale membranaceous and blunt, about {1/3} as long as the perigynium.—Swamps from E. Mass, to N. J. and E. Penn., and southward; frequent.

C. bullàta × utriculàta, Bailey. Perigynium considerably smaller and more spreading, less shining; scales longer and sharper. (C. Olneyi, Boott.)—Providence, R. I. (Olney).

15. C. retrórsa, Schwein. Stout, 2–3° high; culm obtusely angled and smooth or nearly so; leaves broad and soft, roughish, much longer than the culm; spikes 3–5, approximate near the top of the culm or the lowest remote, all but the lowest 1 or 2 sessile, 1–2´ long and very compactly flowered, erect or spreading; perigynium very thin and papery, much inflated, prominently nerved, strongly reflexed; scale very short and small.—Swamps, from Penn. northward; common.—In var. Hárth, Gray, a common monstrous form, the spikes are more or less scattered and peduncled, loosely flowered, and the perigynium less reflexed or spreading.

[=][=] Scales all rough-awned.

16. C. lùrida, Wahl. Variable in size, mostly ranging from 1½–3° high, stout; culm rather obtusely angled and smooth; leaves long and loose, rough; spikes 2–4, variously disposed, the 1 or 2 upper sessile, nearly erect or often drooping, very densely flowered; perigynium thin and turgid, often somewhat shining, rather lightly about 10-nerved, very long and slenderly beaked, ascending; staminate spike single, scales linear, half as long as the perigynium or more. (C. tentaculata, Muhl.)—Swamps, N. Eng. to S. Ill., and southward; abundant eastward. Very variable.—Var. grácilis, Bailey. Plant more slender; spikes 2–3, very small and narrowly cylindrical (1´ long or less, and 3´´ broad or less). Mts. of Vt., Penn., and Tenn.

Var. fláccida, Bailey. Lower, scarcely exceeding 12–15´ in height; spikes 2–4, all sessile and approximate at the top of the culm, small and straight (1´ long or less), dull brown or reddish-brown, loosely flowered and entirely lacking the dense and comose appearance of the type; perigynium very thin and much inflated, the body usually larger than in the type and more gradually contracted into the beak.—N. Y. to N. J.; apparently scarce.

C. lùrida × lupulìna, Bailey. Very like C. lurida, but the spikes usually all approximate or only the lowest separated, erect or spreading, all sessile, green or greenish, often curved; perigynium very long-beaked and ascending; staminate spike one, sessile or very nearly so, strongly resembling that of C. lupulina. (C. tentaculata, var. altior, Boott.)—Mass., Conn., and N. Y.; little known. C. lupulina × retrorsa is distinguished from this by its yellow or straw-colored more scattered spikes which are shorter and always straight, and the loose, larger and more inflated perigynia.