360 North American CijiJeracea, 



sistent. Style 2-cleft, compressed, dilated or tuberculate at 

 the base. Nut biconvex, crowned with the broad persistent 

 tubercle, or rostrate with the persistent style. — Culms leafy ; 

 spikes in lateral and terminal compound cymes ; rays and pe- 

 duncles alternate, with leafy sheaths at the base. 



1. PsiLOCARYA SCIRPOIDES. 



Spikes oblong-ovate, many-flowered ; scales lanceolate- 

 ovate, acute, membranaceous ; nut tumid, obscurely rugose ; 

 style long, rostrate, persistent, much dilated at the base, and 

 decurrent at the edges of the nut. 



Culm obtusely triangular, leafy, smooth. Leaves g:ramineous, 6 — S 

 inches long, 1 — Ij line wide, smooth; sheaths naked at the throat. 

 Cymes pedunculate, one terminal and one from the sheath of each leaf, 

 spreading; rays 1 — 2 inches long, alternate, diverging, with loose, 

 somewhat foliaceous sheatlis, dividing towards the summit into 3 

 or 4 short branches, or compoundly branched ; all the subdivisions alter- 

 nate and sheathed at the base. Spikes 3 — 4 lines long, 20 — 30-flowered, 

 somewhat acute, equally imbricated on every side. Scales very thin, 

 chestnut-coloured, marked with a narrow central nerve, all bearing 

 fertile flowers. Bristles entirely wanting. Stamens constantly 2; 

 filaments slender, firmly attached one on each side of the base of the 

 torus. Ovary oblong, attenuated above into a flat smooth ensiform style, 

 which is 2-cleft one -third of the way down. Nut very tumid and some- 

 what hemispherical on each side, dark brown, obscurely rugose trans- 

 versely; the base abruptly contracted, and surrounded with a short torus; 

 the summit crowned with a large, flat, rostrate, persistent style, which is 

 much dilated at the base, and decurrent at the edges of the nut, so as 

 nearly to surround it with a pale narrow margin. 



Hab. Borders of a pond near North Providence, Rhode 

 Island, T. A. Greene, Esq. ! ; Massachusetts (the precise loca- 

 lity not recorded), collected by the late Dr. H. Little of Bos- 

 ton ; V. s. in Herb. Acad. Nat. Sc. of Philadelphia. 



Obs. I received specimens of this rare and interesting 

 plant about six years ago, from my intelligent friend Mr. Greene 

 of New Bedford, who has shown much zeal in examining the 



