530 CYPERACE^E. (SEDGE FAMILY.) 



bracts long and leaf-like, with very short sheathing bases, much exceeding the 

 culm (about equal to it in No. 106) : staminate spikes 1-5, 



* Perigynia with a very short and thick leak, and with short and thick slighfy 



spreading teeth. LACUSTRES. 



106. C. striata, Michx. (not of ed. 1.) Sterile spikes 2-3, the upper- 

 most stalked ; fertile spikes 1-2, oblong, erect, remote, on very short stalks ; peri* 

 gynia ovoid, abruptly contracted into a slightly serrulate beak, longer than the point- 

 ed purple scale. (C. polymorpha, ed. 1.) Wet places, New Jersey to Vir- 

 ginia, and southward. 



107. C. lacustris, Willd. Sterile spikes 2-5, the uppermost stalked; 

 fertile spikes 2-3, oblong-cylindrical, stout, erect, remote, nearly sessile, or the low- 

 est on a short stalk; perigynia oblong, but little exceeding the lanceolate awned 

 scale ; culm sharply triangular, rough ; sheaths very short, smooth. ( C. riparia, 

 j*r>t/d., not of Curtis.) Swamps and borders of lakes and rivers; common. 

 A robust species, 3 -5 high, with leaves '-$' wide. 



# * Perigynia with an elongated tapering beak, and long widely spreading or recuncd 



sharp and spine-like teeth. ARISTAT^E. 

 i- Staminate spikes 2-5, some occasionally bearing a feiv fertile /lowers. 



108. C. aristata, R. Brown. Fertile spikes 2-4, cylwdrical, erect, re- 

 mote, the lower on partly cxscrted short stalks ; perigynia taperinq from an ovoid 

 base into a deeply 2 -forked beak, longer than the ovate-lanceolate awned scale 

 culm smooth; sheaths and under surface of the leaves pubescent. (C. athcrodes 

 Spreng.) Lake shores and river-banks, N. New York to Michigan, and north- 

 westward. Culm 2 - 3 high : leaves 2" - 3" wide. Fertile spikes 2' - 3' long 

 often rather loosely flowered towards the base. 



109. C. tricllOCarpa, Muhl. Fertile spikes 2 - 3, oblong-cylindrical, erect, 

 remote, one of them sometimes staminate at the apex, the lower on cxscrted 

 stalks, rather loosely flowered towards the base; perigynia very hairy, shaped as 

 the last, longer than the ovate taper-pointed light-brown scale ; culm sharply 

 triangular, smooth except near the top, sheaths and under surface of the kaoea 

 smooth. (C. striata, ed. 1, not of Michx.) Marshes and lakes; common, es- 

 pecially northward. 



-*- Staminate spike solitary, with a filiform bract, occasionally bearing a few 

 fertile flowers towards the apex or base : fertile spikes 3-5, cylindrical, dense- 

 ly flowered, on long cxsertcd and at length drooping stalks : perigynia widely 

 spreading, reflcxed at maturity. 



110. C. COindsa, Boott. Fertile spikes large (l|'-2.f long, and '-' 

 wide), the lowest sometimes very remote; perigynia tapering from a stalked ovoid* 

 ti\:uii/nlar 'MISC. into a long deeply 2-forked beak, the sharp elongated t-th iri<l;li/ .syj/wA 

 ing or somewhat recurved ; scales lanceolate with a long bristle-shaped awn 

 shorter than the mature fruit ; culm rough and triquetrous. (C. furcata, Ell., 

 not of Lapeyr. C. Pscudo-Cyperus, Schw. Sf Torr., Dew., frc., in part, not of L.) 

 Wet places ; rather common. A robust species 2 - 3 high, formerly con- 

 founded with the next, which it greatly resembles; but it differs especially in 

 the larger fertile spikes, longer beak of the fruit, and the longer, smooth ami 

 widely-spreading teeth, giving to the spikes a comose or bristly appearance 



