102 MEMOIRS FEOM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 



line, deeply dissected into narrowly oblong segments. Cyme rather few-flowered with 

 erect branches. Flowers 12-16 mm. in diameter, on rather slender pedicels. Hypan- 

 thium silky ; bractlets linear-oblong, shorter than the narrowly lanceolate acute sepals. 

 Petals obcordate, a third exceeding the sepals. 



It much resembles P. subjuga, but differs in the prostrate or ascending thicker stems 

 and the narrow cyme, the branches of which are not divergent. The terminal leaflets are 

 never 5, as is generally the case in P. subjuga. Following Gray and Watson, I mistook a 

 form of P. dlssecta, with leaves slightly tomentose beneath for P. rubricaulis of Lehmann. 

 I had then seen only a depauperate form of the present species and did not recognize it. 

 Tweedy's specimens from Pike's Peak, Colorado, answer very well both Lehmann's de- 

 scription and plate. When more material has been received and the species made bet- 

 ter known, it may be shown that both P. minufifolia and P. saximontana are forms of 

 this species, but at present they seem to be well defined. The following specimens of 

 P. rubricaulis have been examined : 



Colorado: F. Tweedy, No. 209, 1896; Patterson, 1876; Alice Eastwood, 1892; S. 

 L. Clarke, No. 91, 1895; C. F. Baker, No. 17, 1896; G. E. Osterhout, 1894; No. 12 and 

 13, 1897. 



Alberta: J. Macoun, No. 16736, 1897. 



Wyoming: F. Tweedy, No. 205, 1897. 



85. Potentilla minutifolia Rydb. 



PoterdiUa mbmtifolla Rydberg, Bull. Torr. Bot. Club, 23 : 399. 1896. 



Illustrations: Bull. Torr. Bot. Club, 23: 'pi 275, f. 6-10. Plate 4^,/. 6; fruit- 

 ing hypanthium and calyx,/. 7 ; dissection of flower,/. 8; pistil,/ 9 ; stamen,/ 10. 



Cespitose ; stems about 1 dm. long, slender, 1-2-leaved, sparingly silky or nearly 

 glabrous, slightly striate. Stipules ovate-lanceolate, the lower scarious and brown. Basal 

 leaves very small, with slender petioles 3-5 cm. long, silky-hirsute, slightly grayish 

 beneath, pinnate with two pairs of leaflets, the upper pair and the sessile odd leaflet about 

 5 mm. long, the lower pair only 2-3 mm.; leaflets obovate, incised, with oval rounded 

 segments. Flowers 1 or 2, about 15 mm. in diameter. Hypanthium sparingly hirsute, in 

 fruit 7-8 mm. in diameter ; bractlets oblong, generally obtuse, about half as long as the 

 oblong-lanceolate obtuse or acutish sepals. Petals obcordate, about a half longer than 

 the sepals. 



This somewhat resembles P. rubricaulis, but differs in the small size of the plant 

 and of the leaves, and their short and rounded segments. 



Cohmidu: Wm. M. Canby (Pike's Peak) 1895; Osterhout, No. 11, 1897. 



