MEMOIRS FEOM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 99 



80. Potentilla bipinnatifida Dougl. 



PotentiUa bipinnatifida Douglas ; Hooker, Fl. Bor. Am. 1 : 188. 1833. 



Eat. Man. Ed. 7 : 458; Eat. & Wr. N. A. Bot. 374; Walp. Ann. 2 : 480 ; Don, Gard. 

 Diet. 2 : 558. 



PotentiUa arguta Lelim. Mon. 21 and 62. 1820. Not Pursh, 1814. 



Spreng. Syst. Veg. 2 : 534 ; Schlecht. & Cham. Linnaea, 2 : 26. 



Potentilla agrimonioides var. Bieb. PL Taur. Cauc. 3 : 354, fide Lehraann. 



Potentilla Biebersteiniana Tratt. Eos. Mon. 4: No, 24. 



Potentilla candicans Pisch; Lelim. Rev. Pot. 60. 1856. 



Potentilla Pennsylvanica bipinnatifida Torr. & Gray, PL N. A. 1 : 438. 1840. 



Lehm. Rev. Pot. 60 ; Macoun, Cat. Can. PL 137 ; Hoolc. Journ. Bot. 6 : 220 ; Walp. 

 Rep. 2: 32; Dietr. Syn. PL 3: 186; Rydb. BulL Torr. Bot. Club, 23: 263; Britt. & 

 Brown, 111. Fl. 2 : 214. 



Potentilla Pennsylvania arguta Ser. in DC. Prod. 2 : 581. 1825. 



Illustrations : Plate 39, f. 1; dissection of flower,/. 3; stamen, /. 3; pistil, /., 4; 

 fruiting hypanthium and calyx, /. 5. 



Stems several from a perennial root, erect or ascending, strict and simple, leafy, 

 finely white silky- villous, 3-5 dm. high. Basal leaves many, with petioles 5-10 cm. long, 

 pinnate, with 3 or 4 approximate pairs of leaflets, densely and finely silky above, white- 

 tomentose beneath ; leaflets 2-4 cm. long, obovate in outline, pectinately divided to near 

 the midrib into almost linear, mostly obtuse segments. Stem leaves similar, but short- 

 petioled or subsessile and often subdigitate. Stipules ovate or lanceolate, 2-4 cm. long, 

 sometimes toothed. Cyme dense and contracted. Hypanthium white-silky, in fruit 

 about 8 mm. in diameter ; bractlets oblong-lanceolate, shorter than the ovate sepals. 

 Petals obovate, cuneate, truncate, about equalling the sepals. 



Lehmann regards this as a distinct species in Hooker's Flora Boreali-Americana, but, 

 following Torrey and Gray, reduces it to a variety of P. Pennsylvanica in his Revisio. As 

 he mentions a glabrate form of P. bipinnatifida, he must have had P. litoralis in view. 

 P. bipinnatifida is also much nearer related to that species than to P. Pennsylvanica, hav- 

 ing the same leaf form and general habit, but is more erect and densely silky and tomen- 

 tose. In all the material examined I have found but a single specimen that in any 

 way could be regarded as a connecting link. This, as well as P. Pennsylvanica, it is a 

 plant confined to the northwestern plain region, extending from Saskatchewan and 

 Alberta to Colorado. 



