:. (S::DGE FAT-IILT.) 515 



*- Spikes small ; perigynia (hick and spongy at the base, and with a rigid margin t 

 not dilated. STELLC lAx.E. 



33. C. Stelllilata, Good. Spikes 3-5, distinct, obovoid or roundish at 

 maturity; perigynia ovate from a broad somewhat heart-shaped base, widely 

 spreading at maturity, longer than the ovate acute scale ; achenium ovate, ab- 

 ruptlv contracted into a minute stalk; style slightly tumid at the base. Var. 

 SCIRPOIDES has stutter more approximate 9pUcet t the perigynia ovate from a 

 rounded or truncate base, nairower and less acute scales, and a very short style. 

 (C. scirpoides, ScJJc.) Var. STERILIS has the spikes occasionally dioecious, or 

 the staminate ones with but few fertile flowers, and the pistillate nearly destitute 

 of barren ones ; the culms stouter and rigidly erect ; and the leaves generally 

 glaucous ; achenium rounder, with a moi-e tapering base, and the style scarcely 

 tumid at the base. (C. stcrilis, Schk.) Var. ANGCSTATA has about 4 aggre- 

 gated spikes, with narrowly lanceolate perigynia tapering into a long slightly rough 

 beak, more than twice the length of the blunt scale ; the achenium oblong. 

 Swamps and wet meadows; common, especially northward. (En.) 



- - Spikes rather large: perigynia thickened and spongy on the angles, with a more 

 or less dilated membranaceous margin or wing. OV\LES. 



34. C. syclmocepliala, Carey. Spikes densely clustered, forming a short 

 compound spiked head subtended by 3 very long unequal leafy bracts ; jterigynia taper- 

 ing from an abruptly contracted ovate base into a long slendtr beak, somewhat ex- 

 ceeding the lanceolate abruptly mucronate scale. (C. cyperoides, Dew., not 

 of L.) Jefferson County (Vasey Sf Knieskern) and Little Falls, New York, 

 Vasey. Different in habit from all the rest of this section, and recognized at 

 once by the ovoid compound spike, seated at the base of the long leafy bracts, 

 by which the lower spikes are parti v concealed. 



35. C. arida, Schw. & TOIT. Spikes 8-10, approximate (!' long), oblong- 

 cylindrical, contracted at each end; perigynia narrowly lanceolate (4-5 lines in 

 length), tapering into a long beak more than twice the length of the ovate-lanceolate 

 scale; achenium sessile, narrowly oblong. (C. Muskingumensis, Schw.) Wet 

 meadows. Ohio and Michigan to Illinois and Kentucky. In its characters scarce- 

 ly distinguished from the next, but strikingly different in appearance ; a much 

 larger plant, with long, dry, and chaffy-looking spikes. 



36. C. SCOpfiria, Schk. Spikes 5 - 8, club-shnped, at length ovate, more 

 or less approximate, sometimes forming a dense head: perigynia narrowly lanceo- 

 late, tapering into a long slender beak, longer than the lanceolate pointed scale : ache- 

 nium distinctly stalked, exactly oval. Low meadows ; everywheie common. 

 Spikes brownish or straw-colored wlwm ripe. 



37. C. lagopodioidcs, Schk. Spikes 10-15, approximate; perigynia 

 ovate-lanceolate, nearly ticice (he length of the ovate-olhong rather obtuse scale : ache- 

 nium narrowly oval, on a short stalk. Var. CRISTATA has the spikes closely 

 aggregated, with the perigynia spreading. (C. cristata, Schiv. $* Torr.) Wet 

 fields; equally common with the last, from which it is distinguished only by the 

 more numerous shorter spikes, and shorter less tapering perigynia and scales. 

 The variety has the spikes crowded into an ovate head, to which the diverging 

 points of the fruit give a squarrose appearance. 



