318 PLANTjE NOVtE tiiubbeeian^. 



furnished with a depressed and concave gland. The two partifil petioles are aboutphe 

 length of the main petiole, and are terminated by a single pair of leaflets, of a thick 

 and firm texture, and of an extraordinary size for this genus, being often an inch and 

 a half in length, and li to 2 inches in breadth, and with their strong and salient 

 nerves, as well as their branching veins, equally conspicuous on both sides. The 

 foliage, inflorescence, and general habit of the plant would refer it rather to Pitheco- 

 lobium than to any other genus. But the stamens are ochroleucous and not monadel- 

 phous : they are barely three lines long, and less than twice the length of the corolla. 

 The tube of the latter is glabrous where it is covered by the somewhat turbinate and 

 flve-toothed calyx. Ovary oval-oblong, short-stipitate, glabrous, containing several 

 ovules. Unless the fruit furnishes some peculiar characters, the plant must remain in 

 the genus Acacia. 



PoTENTiLLA Thurberi (sp. nov.) : multiceps, viridis, subpubescens ; caulibns e rhi- 

 zomate crasso adscendentibus (pedalibus et ultra) plurifloris ; foliis glabellis membra- 

 naceis, radicalibns digitatis 5 - 7-foliolatis, petiolo patentim piloso, foliolis sessilibus 

 obovato-oblongis grosse serratis, caulinis parvulis sxibsessilibus trifoliolatis ; stipulis 

 2 - 3-dentatis ; floribus laxe cymoso-paniculatis longiuscule pedicellatis ; segmentis 

 calycinis accessoriis oblongo-lanceolatis sepala gequantibus petalis atro-sanguineis ob- 

 cordato-rotundis vel emarginatis paullo brevioribus ; receptaculo conico breviter vil- 

 loso ; acheniis glabris vix rugulosis ; stylo fere terminal!. — Near Santa E,ita del Cobre, 

 New Mexico; August, 1851. — This remarkable species, which appears not to have 

 been seen either by Mr. Wright or Dr. Bigelow, — who largely collected in the same 

 region, — is one of those which invalidate the genus Comanim. It is manifestly allied 

 to the Mexican P. comaroides, of Humboldt, though very distinct from it, and belongs 

 to the Herbacece, Multicipites, Ser. 2, Multiflorce, Rectce, of Lehmann's recent arrange- 

 ment. Petioles of the radical leaves about 3 inches long ; the leaflets li to 2 inches 

 long, green both sides, coarsely and obtusely serrate almost to the base. Leaflets of 

 the lowest cauline leaves nearly similar ; the others with fewer teeth ; the uppermost 

 reduced to small and cuneate three-toothed bracts. Inflorescence minutely pubescent. 

 Pedicels 5 to 12 lines long. Calyx sparingly pilose. Petals about 3 lines long. Sta- 

 mens 25 to 30, with slender and subulate filaments. Disc nearly as in P. (Comanim) 

 jyaliistris. Eeceptacle enlarged in fruit, and scrobiculate.* 



* Specimens of this striliing Potentilla have just come to hand, collected by Dr. Henry, of the United States 

 Army, on the Rio Mimbres, and by Dr. Bigelow, I believe from the mountains east of the Rio Grande. 



