13. Eleocharis Smallii Britton. Small's Spike-Rush

Fig. 770

E. Smallii Britton, Torreya 3: 23. 1903.

Perennial by rootstocks; culms rather stout, about 20 high, and 1"-1 1/2i" thick; top of the basal sheath oblique; spikelet cylindric to conic-cylindric, acute, about 8" long, about as thick as the culm; scales lanceolate-oblong, acuminate; bristles very slender, equalling the achene and tubercle or a little longer; achene dark brown, obovate, turgid-lenticular, somewhat shining, nearly 1" long, rounded at the top, the tubercle bulb-like, constricted at the base, one-fourth as long as the achene and about one-half as wide, rather abruptly tipped.

Valley of the Susquehanna River, Pennsylvania. Aug-Sept.

14. Eleocharis Acicularis (L.) R. & S. Needle, Or Least, Spike-Rush

Fig. 771

Scirpus acicularis L. Sp. PI. 48. 1753. Eleocharis acicularis R. & S. Syst. 2: 154. 1817.

Perennial by filiform stolons or rootstocks, culms tufted, finely filiform or setaceous, obscurely 4-angled and grooved, weak, erect or reclining, 2'-8' long. Sheaths truncate; spikelet compressed, narrowly ovate or linear-oblong, acute, broader than the culm, 3-10-flowered, 1 1/2"-3" long, 1" wide; scales oblong, obtuse or the upper subacute, thin, pale green, usually with a narrow brown band on each side of the midvein, deciduous, many of them commonly sterile; bristles 3-4, fragile, fugacious, shorter than the achene; stamens 3; style 3-cleft; achene obovoid-oblong, pale, obscurely 3-angled with a rib on each angle and 6-9 lower intermediate ribs connected by fine ridges; tubercle conic, acute, one-fourth as long as the achene.

In wet soil, Newfoundland to British Columbia, New Jersey, Missouri, Mexico and California. Also in Europe and Asia. Sometimes entirely sterile. July-Sept.

15. Eleocharis Wolfii A. Gray. Wolf's Spike-Rush

Fig. 772

Scirpus Wolfii A. Gray, Proc. Am. Acad. 10: 77. 1874. Eleocharis Wolfii A. Gray; Britton, Journ. N. Y. Micros. Soc. 5: 105. 1889.

Perennial by short rootstocks, culms very slender, erect, flattened and 2-edged, 8-18' tall. Upper sheath oblique, scarious, hyaline-tipped; spikelet oblong or ovoid-oblong, terete, acute, thicker than the culm, 2"-3" long, nearly 1" in diameter; scales ovate, obtuse or the upper acute, thin, pale green with purplish-brown bands, tardily deciduous; bristles none (or perhaps early deciduous); style 3-cleft; achene obo-void, obscurely 3-angled, longitudinally 9-ribbed, the ribs transversely connected by minute ridges; tubercle depressed-conic, much shorter than the achene.

In wet meadows, Illinois. Minnesota and Iowa. June-Aug.

16. Eleocharis Simplex (Ell.) A. Dietr. Twisted Spike-Rush

Fig. 773

Scirpus simplex Ell. Bot. S. C. & Ga. 1: 76. 1816. Scirpus tortilis Link, Jahrb. 3: 78. 1820. Eleocharis tortilis Schultes, Mant. 2: 92. 1824. Eleocharis simplex A. Dietr. Sp. PI. 2: 78. 1833.

Annual, roots fibrous, culms tufted, filiform, sharply 3-angled, pale green, erect or reclining, twisting when old, 1°-1 1/2° long. Sheaths obliquely truncate, i-toothed; spike-let ovoid or oblong, subacute, several-flowered, 2"-3" long, about 1" thick, much thicker than the culm; scales firm, pale, ovate, mostly obtuse; bristles 4-6, rigid, retrorsely barbed, about equalling the achene and tubercle; stamens 3; style 3-cleft; achene obovoid, obscurely 3-angled, strongly reticulated, longitudinally about 18-ribbed; tubercle cap-like or conic, truncate at the base, one-fourth to one-half as long as the achene.

In wet soil, New Jersey to Florida and Texas, near the coast. July-Sept.