North American Cyperacece. 369 
remarkable, as also its somewhat peculiar habit. Each spike- 
let, as in the preceding species, produces a single perfect flower 
at the :5ummit, and all the scales are empty except the upper- 
most. Were it not for its distinctly bifid style, this plant might 
perhaps be properly referred to Cephaloschcemis of Nees ab 
Esenbeck. 
18. CERATOSCHGENUS, N. ah E. 
Spikelets producing a single perfect, and 1 — 4 stami- 
nate flowers. Scales loosely and somewhat bifariously im- 
bricated, the lower ones empty, the uppermost staminate or 
abortive. Perigynium composed of 5 or 6 compressed, rigid 
or cartilaginous, antrorsely hispid or scabrous bristles, which 
are dilated and somewhat connate at the base. Stamens 3. 
Style simple, or minutely bidentate. Nut coriaceous, com- 
pressed, smooth, crowned with the very long, distinct, indurated 
and persistent, upwardly scabrous style. — Culms triangular, 
leafy ; corymbs mostly compound or decompound ; spikelets 
large, clusteredc 
1. C. longirostris. 
Schoenus longirostris, Michx..' fl. 1. p. 87; Muhl. ! gram. p. 7. 
S. corniculatus, Lain'Tc. ill. gen. 1. p. 137. 
Rhynchospora laxa. Vahl, enum. 2. p. 231 ; Torr. ! fl. \. p. 58. 
fl. longirostris, Ell. sk. 1. p. 59. 
U. corniculata, Gray ! monogr. I. c. p. 205. 
2. C. MACROSTACHYS. 
Rhynchospora macrostachya, Torr. ! in Gray, monogr. I. c. p. 206. 
Obs. These two plants, in accordance with the views now 
generally adopted in the construction of genera in Cyperaceae, 
cannot be allowed to remain in the genus Rhynchospora, from 
which they also differ remarkably in habit. It was suggested 
in the Monograph of N. American Rhynchosporae, that thej 
