88 EEPOHT OF THE STATE UOTANIST. 



Sand}' soil. Rare. Essex and Saratoga counties. June, July. 

 Sometimes the mature perigynia become reddish-brown or 

 almost chestnut color. 



106. Carex riparia Curtis. 



Stoloniferous ; stems 2'-B^° liigb, stout, acutely angled, rough 

 above the middle, flaccid at the base ; leaves longer than the 

 culm, 2"-5 " wide, mostly smooth on the upper surface, rough 

 beneath, erect or spreading, glaucous; staminate spikes 2-5, 

 cylindrical, the highest 1 J' in length on a stalk 1' long or less, 

 the lowest with a setaceous bract l'-l|^' long; pistillate spikes 

 2-4, densely flowered, or loosely at the base, cylindrical or 

 clavate, 14'-3' long, 4:"-5" thick, distant, the uppermost subsessile, 

 the others short-peduncled, all erect, or the lowest sometimes 

 spreading ; bracts leafy, equaling or exceeding the culm ; 

 perig3^nia oblong-conical, flnely nerved, smooth, gradually taper- 

 ing into a short conical bidentate beak, a little longer than the 

 ovate-lanceolate, awned scale; achenium narrowly obovate, 

 apiculate. 



Bogs, swamps and wet places. Common. June. 



This is readily determined by the large erect spikes and 

 oblong-conical, finely-nerved, olive-brown perigynia. It is 

 C. lacustris Willd. 



Staminate spikes 1-5, stalked or the lower ones sessile, rarely 

 fertile at the apex ; pistillate spikes 1-4-, cylindrical or short- 

 oblong, densely or subdensely flowered, subapproximate, distant 

 or remote, sessile or nearly so, erect ; bracts leafy, the lower 

 short-sheathing or sheath less, mostly surpassing the culm; 

 perigynia turgid, ovate-lanceolate, nerved, pubescent or smooth, 

 with a long bifurcate beak, the teeth mostly recurvedspreading. 



Perigynia smooth aristata. 



Perigynia hairy 1 



1 Staminate H])ikes 1-2 liirta. 



1 Staminate spikes 2-5 trichocarpa. 



107. Carex liirta L. 

 Stoloniferous ; stems 8' -24' high, slender, erect or spreading, 

 smooth below the summit, obtusely angled ; leaves shorter than 

 the culm, or, in low forms, the radical surpassing it, 1"-14-" wide, 



