194 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 



lanceolate, more or less toothed, about 1 cm. long ; basal leaves several, with villous 

 petioles 5-10 cm. long, pinnate ; leaflets 4 or 5 pairs, glabrate or slightly pubescent, 2-5 

 cm. long, broadly obovate and obtuse, coarsely serrate and incised with ovate teeth ; stem 

 leaves with fewer more acutish leaflets. Cyme Avith rather elongated upright branches, 

 but with short pedicels, and therefore rather long and narrow. Flowers 10-18 mm. 

 in diameter. Hypanthium densely glandular-viscid, villous, not much enlarged in fruit, 

 8-10 mm. in diameter. Petals broady obovate, Avhite, turning yellow in drying, a little 

 longer than the sepals. Bractlets lanceolate, much smaller than the ovate-lanceolate 

 sepals. Stamens about 25 ; anthers flat, slightly cordate at the base. 



This species resembles D. arguta, but is more slender. The branches of the cyme are 

 more elongated, hypanthium smaller, stamens fewer and the leaflets rounder and nearly 

 glabrous. The leaves most resemble those of D. ghUinosa, from which the plant differs 

 mostly in its smaller and white petals and in the narrow cyme. It has been labelled 

 Potentilla arguta whenever collected and is apparently a rather rare plant, representing 

 that species in the valleys of the northern Rockies. The following specimens have been 

 examined : 



Montana: Rydbei-g; J. H. Flodman, No. 602, in the Elk Mountains ; No. 603 in the 

 Spanish Basin ; No. 604 (type) near Bozeman ; No. 605 in the Bridger Mountains, all in 

 1896; F. L. Scribner, No. 42, 1883. 



Washington: Wilkes' Exp., No. 817; C. V. Piper, No. 1528. 



Assiniboia: J. Macoun, No. 41, 1880. (?) 



Idaho: A. A. & Gertrude Heller, No. 3230, 1896. 



Wyoming: T. H. Burglehaus, 1894; E. Stevenson, No. 72, 1894; Nelson, No. 2151, 

 1896. 



Alberta {f): Macoun, No. 623, 1885 (Kananaskis). 



3. Drymocallis pseudorupestris, 



.?Pofen<i/k rwjsesiHs Presl, Epim. Bot. 198. 1849. Not L. 



Potentilla glandulosa var. Nevadensis Wats. Bot. Cal. 1 : 178. In part. 1876. Not 

 P. Nevadensis Boiss. 



Potentilla pseudorupestris Rydberg, Bull. Torr. Bot. Club, 24: 250. 1897. 



Illustrations : Bull. Torr. Bot. Club, 24 : pi. 307. Plate 103. 



Stem erect, slender, striate, 2-5 dm. high, branched, with slender ascending branches, 

 sparingly glandular-villous. Stipules ovate, more or less toothed. Basal leaves several 

 with rather short petioles; leaflets 3 or 4 pairs, sparingly and finely pubescent or gla- 

 brate, the terminal one obovate, cuneate-flabelliform, the lateral ones obliquely elliptic 



