North American Cyperacets. 363 



the Annals, is so full that it was quite unnecessary to describe 

 the plants anew : I have therefore merely given his list of the 

 species with some alterations, which he has thought it advisalle 

 to make, together with some valuable additional matter which 

 has been received since his monograph was written. 



17. RHYNCHOSPORA, VaM. 



Flowers perfect or polygamous. Spikelets few-flowered. 

 Scales loosely imbricated, or obscurely bi-trifarious ; the 

 lowermost smaller and empty; one, two, or three of the others 

 bearing a perfect flower ; the remainder being ctaminate or 

 empty, or sometimes (as in R. miUacca Sf cadvca,) all except 

 the outermost scales fertile. Perigynium composed of 6 

 (sometimes 10 or 12) plumose or naked, retrorsely or an- 

 trorsely denticulate or scabrous bristles. Stamens 3 (rarely 

 2, 6, or 12). Style bifid. Nut crustaceous, lenticular or 

 subglobose, smooth or transversely rugose, crowned with the 

 dilated, persistent and distinct base of the style. — Culms more 

 or less triangular, simple, leafy ; inflorescence terminal and 

 axillary, corymbose, paniculate or fascicled, loosely or densely 

 clustered. 



Rhynchospora, Vahl, emim. 2, p. 229 ; R. Brown, prodr. 

 1. p. 229; Nutt. gen. 1. p. 33; Lestib. ess. fam. Gyp. p. 37 ; 

 Elliott, si'. 1. p. 57; Gray, monogr. inann. lye. nat. hist. New 

 York, 3. p. 191. (excl. R. corniculata &f macrostachya) ; Nees 

 ah Esenh.in Wight'' s contrib. p. 71. a7id in Linncea, 9. p. 297. 



Species of Schoenus, Linn., Lani'k., Michx., Muhl., &c. 



Chaetospora (partly), Humb. Bonpl. a?id Kunth, syn. pi. 

 equinoc. orb. nov. 1. p. 157. 



■§ 1. Nut subglobose-ovate ; bristles of the perigynium densely 

 woolly. — Erioch^te. 



Obs. The species of this section are allied to Chcetospora, 

 R. Brown, from which they are distinguished h their bifid 



