Chapter C: STRICTA x FILIFORMIS. Leaves and culms very slender; spikes short (1'

long or less), sessile and compact, the upper 1 or 2 scarcely bracted, pallid; perigynium small, smooth.--Keweenaw Co., Mich. (_Farwell_.) Exactly intermediate between the two species.

35. C. aquatilis, Wahl. Large and stout, glaucous, 2--4 deg. high; culm very obtuse and smooth; leaves exceedingly long, broader than in the last, the bracts broad and prolonged far beyond the culm; spikes 3--5, 1--2' long, very compact or the lowest sometimes attenuate below, erect, thick (3'' broad or less); perigynium round-ovate or broadly elliptic, nerveless, greenish, imbricated; scale obtuse and much shorter and narrower than the perigynium.--Swamps and lake-margins, N. Eng. to Minn.; not common. (Eu.)

36. C. lenticularis, Michx. Rather slender but erect, pale throughout, 1--2 deg. high; culm sharp, usually slightly rough above; leaves very narrow, numerous, much surpassing the culm; spikes 3--6, more or less aggregated or the lowest remote, the terminal androgynous or staminate, mostly sessile, erect; perigynium ovate, minutely granular, brown-nerved, the tip empty and entire; scale pale and obtuse, about 1/2 the length of the perigynium.--Gravelly borders of ponds and lakes, northern N. Eng. to Minn.; mostly local.

[=][=] _Spikes widely spreading or drooping._

37. C. torta, Boott. Slender but erect, 11/2--21/2 deg. high, in clumps, with exceedingly tough and cord-like roots; culm rather sharp, smooth or roughish above; leaves flat and rather soft, those of the culm very short; spikes 3--5, mostly somewhat approximate or the lower remote, the upper sessile and ascending but the others drooping, long and slender (often 3' long, 2'' broad or less); perigynium lance-ovate, thin and green, nerveless, the slim upper half empty and more or less tortuous, the beak entire or erose; scale purple-margined and very obtuse, shorter than the perigynium.--Cold banks and swamps, Vt. to N. C.; infrequent.

[++][++] _Stigmas 2; scales long-acute and ascending._

38. C. salina, Wahl., var. cuspidata, Wahl. Rather stout, 1--21/2 deg. high; culm rather sharp, smooth; leaves narrow but flat; spikes 2--4, somewhat approximate, the lowest 1 or 2 very short-stalked, erect, short (11/2' or less) and rather thick, the lower subtended by leaf-like bracts 3--4' long; perigynium elliptic, somewhat granular, marked with 2 or 3 nerves or nerveless, the minute beak entire; scale brown-margined, produced into a lighter and rough awn much exceeding the perigynium. (C. salina, _Man._)--Salt marshes, Mass., and along the coast northward; rare in the United States. (Eu.) Anomalous forms, which appear to be hybrids, have been separated as