CliASS IV. Cil.UMACEOUS ENDOGENS. 



Flowers with glumes ; or floral oi'gans enclosed in imbricated 

 biactb, and arranged in spikelets, having no proper perianth (calyx 

 oi corolla). Ovary with one cell containing a solitary ovule and 

 becoming a one-seeded fruit (achenium or caryopsis). 



spirally or ( Ach. not 

 irregularly < enclosed. 



Order CLX. CYPERACE^— Sedges. 



Herbs mostly perennial, coarse, gntss-like, ca;spito.se. Root fibrous or rarely tuberou.s. 



aiemi (culms) usually solid with pith, generally without joints or nodes, and triangular. 



Lw. with their sheaths entire. Injior&scence. mostly capitate or spicate. 



F.'s. perfect or monoecious, solitary in the a-\il of each bract (glume, scale). 



per. wanting, or represented by a few hypogynous bristles, or a cup-shaped or saccate perigyiuum. 



Sta. definite (1—12), mostly 3. Anthers fixed by their base, entire, 2-celled. 



Dva. generally either surrounded by bristles, or invested in the sacaiz perigynium. Ovule erect. 



Sty. 2 or 3, more or less united. Stigmas undivided, rarely bifid. 



•Tr. an achenium. Embnjo in the end of the albumen next the hilum. 



Genera 112, species 2000. The sedges abound in almost all countries and climes of the globe, and in all 

 localities, but are more common in the meadows, marshes and swamps of the temperate zones. About 

 25 genera and 340 species are known in North America. 



Properties.— They are in general little used for food or in the arts. Their coarse herbage is often eaten 

 by cattle, but they are nearly destitute of the sweet and nutritious properties of the grasses. The leaves 

 of some of the larger species are used in Italy to bind flasks, and in weaving the bottoms of chairs. 

 Yet, although of so little apparent value, their vast numbers authorize the belief that they subserve 

 many highly important ends iu the economy of nature. 



Conspectus of the Genera. 



("Flowers in axillary, racemose spikelets Dulichium. 1 



I 4 Spikelets linear, many-flowered, distinct, loose. Cyperus. 2 



distichously 1 < ^ Ach. triangular. Mariscus. 3 



imbricated. LFls. all terminal. ( Spikelets 1—2-fiowered. in hds. ? Ach lenticular. Kyllingia. 4 



f Perigymumof3ovate,unguiculate petals, with 3 bristles. Fuirena. 5 



I Leaves 0. Sidke solitary, terminal. . Eleocharis. 6 



(• Bristles 3—6 Scirpvs. 7 



I Bristles numerous, long. . Eriophornm. 8 



Leaves 1 4 Style 2-cletl. . Fivihristylis. 9 



present. . I Bristles 0. \ Style 3-cleft. . Trichelostylis. 10 



^ Bristles 3—6. Sty. deciduous. Scirpus. 7 



Flowers all lateral. ( Bristles 0. Leaves radical. . Hemicarpha. 11 



i Style short, bulbous at base. Rhynchospora. \3 



\ Flowers CErist. 3— 6. (Style very long, horn-like. . Ceratoschasniis.li 



I both I ( Spikelets 20— 30-flowered. . Psilocarya. \'l 



I axil. and) < Spikelets t Ach. corky, brown. CVad/«7«. 15 



..._^ ^ ._Ltermin. L Bristles 0. ( few flwrd. < Ach. bony, white. Scleria. 16 



.imbricated. (Achenium enclosed in a saccate perigynium. Fls. declinous. . Carex. 17 



Tribe 1. CYPEREiE. — Flowers 5- Spikelets distichously imbricated. 

 1. DULICHIUM. 



Gr. Svct}, two, \tt^riv, scale; alluding Vo the glumes in two rows? 



Spikelets linear-lanceolate, snbcompressed ; glumes sheathing, 

 closely imbricated in 2 rows ; style long, bifid, the persistent base 

 crowning the compressed achenium ; ovary invested with setas. — 

 Stem leafy. Spikes axiUciry^ racemose. 



D. SPATHACEUM. Pers. (Cj'perus. Linn. Scirpus. Michx.) 

 (Si. round, leafy and somewhat 3-sided abov^e, thick, sheathed below; ivs. 

 alternate, pointing 3 ways, 2—4' by 3" ; sheaths tubular, shorter than the inter- 

 no(ies; spikes axillary from within the sheaths and terminal, each consisting 

 of 8 — 10 linear-lanceolate, alternate spikelets in 2 rows ; spikelets 5 — 7-flowercd, 

 nearly an inch in- length; glumes linear-lanceolate. — % Marshes, borders of 

 streams, U. S. and Can. Aug. 



2. CYPERUS. 

 Spikelets compressed, distinct, many-flowered ; glumes imbricated 

 in two, opposite rows, nearly all with a flower enclosed ; ovary generally 

 without seto3. — Mostly %. Stem simple, leafy at base, mostly triangu- 

 lar, bearing an involucrate, simple or ccmpound uvibel at lop. 



