362 North American Cyperacece. 



about 3 lines long, ovate, terete, 16— 20-flnwered. Scales ferruginous, 

 of a pretty firm and somewhr. coriaceous texture, minutely and pulver- 

 ulently pubescent, strongly 1-nerved so as to appear almost carinate. 

 Stamens constantly 2. Style (above the tubercle) filiform, equal, 2-cleft 

 half-way down, separating early and completely from the tubercle. Nut 

 orbicular, moderately convex on each side, marked with strong undulate 

 transverse wrinkles, of a light brown colour, margined. Tubercle gray, 

 much dilated, closely sessile, somewhat 2-lobed at the base ; the apex 

 very blunt. 



Hab. Texas, T. Drummond! 



Obs. This species resembles the preceding, but it differs 

 in its much larger size, decompound cyme, many-flowered 

 spikes, subcoriaceous scales, and in some other respects. It 

 was distributed in the first collection of Mr. Drummond's 

 Texian plants, under the No. 279. The last two species differ 

 so much from F. scirpoides, that they might almost be referred 

 to a separate genus. They are nearly related to Rhynchospora, 

 but want the hypogynous bristles, and bear the same relation 

 to that genus that Isolepis bears to Scirpus. In P. scirpoides 

 the style is almost wholly persistent, compressed and subulate, 

 without any distinct tubercle ; while in P. rhjnchosporoides and 

 p. Texensis it is very caducous, with the exception of the base, 

 which is enlarged into a tubercle of an entirely different texture 

 from the nut. To the latter section belongs another species of 

 which I have had two varieties in my herbarium ; one from 

 St. Vincent, sent to me without a name by Dr. Lindley, the 

 other received from Mr. Arnott, under the name of Schcenus 

 Teneriffce, Vent. Mss. The culm is very slender, the branches 

 of the cyme filiform and divaricate ; the spike 2 — 3-flowered, 

 minute ; the nut lenticular, corrugated, and crowned with a 

 short apiculate tubercle. 



The following revision of the North American species of 

 Rhynchospora and Ceratoschoenus was prepared by Dr. Gray. 

 His valuable Monograph contained in the present volume of 



