Scirpus. CYPERACEjE. 357 



sheaths loose at the throat, several of the upper ones bearing umbels. Terminal umbel largest, 

 somewhat paniculate, at first erect but finally pendulous ; the lateral ones sometimes wanting. 

 Spikes 3-4 lines long. Scales loosely imbricated at the tip so as to appear somewhat squar- 

 rose, ferruginous, with a somewhat prominent keel. Bristles very slender, smooth, crisped 

 and entangled, at maturity projecting a little beyond the scale. Stamens 3. Style somewhat 

 unequally 3-cleft, smooth. Achenium obovate, acuminate, obtusely angular externally, flatlish 

 on the outer side, minutely papillose, pale brown when ripe. 



Boggy places ; near Poughkeepsie (Mr. P. Dudgeon). I have seen no specimens of this 

 plant, collected within the limits of our State, except those gathered by Mr. Dudgeon many 

 years ago ; but it will probably yet be found abundantly in some of the counties bordering 

 Pennsylvania. 



6. ERIOPHORUM. Linn. ; Tor r. Cyp. p. 334. cotton-grass. 



[ Named from the Greek, crion, wool, and phero, to bear ; the achenia being surrounded with long soft hairs.] 



Scales of the spike imbricated on all sides, usually membranaceous, numerous. Bristles 

 (hairs) of the perigynium numerous (rarely as few as 6), capillary, flat, very long, collected 

 into fascicles at the base of the achenium, and forming a silky or woolly tuft. Stamens 3. 

 Style 3-cleft, simple at the base, deciduous. — Culms mostly leafy. Spikes terminal, rarely 

 solitary, usually in a more or less compound umbel or cyme ; when mature, clothed with 

 long silky hairs. 



* Spike solitary. 



1. Eriophorum alpintjm, Linn. (Plate CXL.) Alpine Cotton-grass. 



Culm acutely triangular, filiform, somewhat rough, with short subulate leaves at the base ; 

 spike oblong ; scales somewhat coriaceous, keeled ; hairs 6, crisped. — Linn. sp. 1. p. 53 ; 

 Engl. hot. t. 311 ; Torr. fl. 1. p. 65, and Cyp. p. 334 ; Bigel. fl. Bost. p. 23 ; Beck, bot. 

 p. 427; KuntJi, enum. 2. p. 176. E. Hudsonianum, Michx. fl. 1. p. 334. Trichophorum 

 alpinum, Pursh, fl. 1. p. 57 ; Muhl. cat. p. 7. T. alpinum, (3. Hudsonianum, Pers. syn. 1. 

 p. 70. T. Hudsonianum, Nutt.gen. 1. p. 36. 



Rhizoma creeping, throwing up numerous filiform culms, which are naked except near the 

 base. Leaves 3-8 lines long, pungent, erect, triangular and channelled on the upper side : 

 sheaths closely embracing the culm ; the lowest ones nearly naked, or only with cuspidate 

 rudimentary leaves. Spike 3 lines long, somewhat compressed. Scales oblong-lanceolate, 

 obtuse, yellowish brown ; the lowest one bractlike, somewhat mucronate, and nearly as long 

 as the spike. Hairs 4-5 times as long as the scale, constantly 6, white, flat and membrana- 

 ceous, more or less crisped. Stamens 3? : filaments capillary, elongated. Style filiform, 3- 

 cleft to about the middle. Achenium compressed-triangular, acuminated with the base of the 

 style, pale brown, dull. 



