676 CLX. CYPERACEiE. Carex. 



1. Perigynium cup-shaped, lobed, repand or annular. 



1. S. RETICULARIS. MichX. 



Sf. 1 — 2f high, triangular, rather slender; lis. 1" wide, channeled, radical 

 6 — 12' long, cauline i'ew, much shorter ; fascicles 2 — 5, lateral and terminal, 

 distant, loose-flowered, subsessile ; spikclets somewhat in pairs, the (^ many- 

 flowered, at the base of the (J; glume light brown, ovate, acuminate; sta. 2; 

 perig. 3-lobed ; ach. globose, of a dead white, f " diam., conspicuously reticulated 

 and deeply pitted. — Borders of ponds, R. I., Olncy ! to Flor. The achenium is 

 a curious and beautiful object. 



2. S. LAXA. Torr. (S. reticularis. Muhl.) 



St. 1 — 2f high, weak, difluse, acutely triangular, slender ; Ivs. flat, 2" 

 wide, smooth ; fascicles about 3, one terminal, the others lateral and very re- 

 mote ; ped. 2—6" long, compressed, slender, often recurved ; spikclets distant, in 

 pairs, the sterile at the base of the ^ ; sla. 2 ; perig. deeply 3-lobed ; ach. about 

 1" diam., globose, whitish, marked with brown, hairy, transverse ridges and 

 pits. — Near the sea coast, IST. J. to Flor. Sept. 



3. S. PANUIFLORA. Muhl. 



St. 10 — 16' high, triangular, slender, smoothish; Irs. narrow, nearly 

 smooth ; sheaths pubescent ; fascicles 2 — 3, lateral and terminal, lew-flowered, 

 the lateral ones on long peduncles ; bracts foliaceous, ciliate ; spikclets in pairs ; 

 glumes membranaceous, acute ; 9 spikclct of 3 ovate, mucronate glumes, some- 

 what ciliate on the keel; sly. 3-clelt; ach. globose, rough, white and shining; 

 perig. a narrow ring upon which are 6 roundish, minute, tubercles. — N. Y. 

 (^Bradley), N. H. (Carey), to Car. Aug. 



p. Fascicle solitary, terminal, (apparently lateral) sometimes with a small 

 one near the base of the stem. — Ohio, Sullivant ! 



4. S. TRiGLOMERATA. Michx. Whip-grass. 



St. erect, acutely triangular, rough, leafy, 3 — 4f high ; Ivs. linear-lanceo- 

 late, rough-edged ; spikclets lateral and terminal, alternate, in about 3 subsessile 

 fascicles, and much shorter than the leafy bracts ; glumes ovate, cuspidate, dark 

 purple ; ach. globose, smooth and polished, while, nearly 2" diam. when ripe. — 

 Swamps, in nearly all the states. June, July. 



§ 2. Hypoporum. Perigynium 0. 



5. S. VERTiciLLATA. Muhl. (Hypoporum verticillatum. Nees.) 



St. 6 — 8 — 12' high, triquetrous, slender, glabrous ; Ivs. linear, narrow and 

 flat, shorter than the stem ; fascicles 4 — 6, sessile, few-flowered, appearing as if 

 verticillate ; bracts minute, setaceous, about as long as the fascicles, scabrous 

 upward ; scales of 9 ovate, smooth, scabrous and keeled ; ach. globose, rugose, 

 a little more than \' diam., abruptly mucronate and somewhat 3-sided at base. 

 — Very abundant in Junius, N. Y., Sartwell, to Car., W. to Ohio, Sullivant! 



Tribe 4. CARICE^. — Flowers diclinous. Scales of the spikes imbricated 

 on all sides. Achenium wholly enclosed in an urceolate or bottle-shaped 

 perigynium. 



18. CAREX. * 



Spikelets 1 or more, either androgynous (witti both staminate and 

 pistillate flowers), or with the two kinds in separate spikelets, rarely 

 dioecious; glumes single, 1-flowered, lower ones often empty; sta- 

 mens 3 ; stigmas 2 or 3; perigynium of various forms, 1-valved, per- 

 sistent, enclosing the lenticular or triangular achenium. 

 I. Stigmas two. Achenhmi double convex. 

 A. Spike single. 1. Moncecious. 



1. C. CAPITATA. 



Spike capitate or nearly globose, (^ at the summit ; fr. (perigyniurri) round- 

 ish-ovate, close, compressed, convex-concave, glabrous, acutish, longer than the 

 ovate and rather obtuse glume ; Ivs. slender. — Heights of the White Mts., Robbins. 



* By Prof. C. Dewp.v. D. D. See Preface. 



