MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 117 
ovate, acuminate, green and more or less toothed with lanceolate teeth. Basal leaves 
with petioles 10-20 em. long, irregularly pinnate, silky-villous beneath, especially 
when young and on the rachis and the veins, more glabrous above; leaflets 4-7 pairs, 
obovate-oblong, 3-6 em. long, coarsely serrate, more or less decurrent on the rachis, espe- 
cially the uppermost, which often are confluent. Stem leaves similar but short-petioled 
and with fewer leaflets. Bractlets lanceolate, equalling or sometimes even exceeding 
the sepals. Petals about 8 mm., obcordate, about a fourth longer than the sepals. Sta- 
Stamens 25. 
It is strange that this strongly marked species should not have been described before 
1893. It was collected by Hall and Harbour in 1862, Wm. A. Bell in 1867, and G. R. 
Vasey in 1881. The first specimens were included by Dr. Gray in P. Hippiana. On the 
label of Bell’s specimen is written: “Durand suggests P. rivularis. Gray says no !— 
perhaps P. campestris.” One of Vasey’s specimens is labeled Potentilla Thurber. 
P. ambigens is the tallest of the group, 6-7 dm. high, rather sparingly grayish silky. 
The leaflets are 3-4 em. long, coarsely serrate and more or less decurrent on the rachis. 
The following specimens have been examined: 
Colorado: Hall & Harbour, nos. 158 and 162, 1862 (both only in part); 1D. Vey 
Greene; Osterhout, 1893. 
New Mexico: Wm. A. Bell (Ratan Mountains), 1867; G. R. Vasey (Las Vegas), 1867 
1881; E. O. Wooten, no. 468, 1897 (White Mountains). 
104. Potentilla crinita Gray. 
Potentilla crinita Gray, Mem. Am. Acad. 1849: 41. 1849. 
Lehm. Rev. Pot. 63 ; Walp. Ann. 2: 480. 
Wats. Proc. Am. Acad. 8: 555; Coult. Man. Rocky Mts. 84; Rydb. Bull. Torr. Bot. 
Clubs 24s ak 
Litustrations: Lehm. Rev. Pot. pl. 21. Puarp 54, f. 1; dissection of flower, 
f. 2; pistil, f. 3; stamen, f. 4; fruiting hypanthium and calyx, f. 5. 
Stems several from the rootstock, ascending, 2-8 dm., few-leaved, diffusely few- 
branched, silky-pilose. Stipules 1-2 em. long, ovate-lanceolate, acuminate, subentire. 
Basal leaves many, short-petioled, pinnate, silky-villous (pubescence projecting long out- 
side the tips of the leaves), nearly smooth on the upper surface; leaflets 5-7 approximate 
pairs, cuneate, 1.5-2 em. long, toothed at the apex, generally remaining conduplicate. 
Stem leaves few, small, only 1 or 2 pairs. Bractlets lanceolate, acute, a little shorter 
than the ovate-lanceolate acute sepals. Petals obovate, deeply retuse, exceeding the calyx. 
This is similar in habit to P. Breweri, but distinguished by its conduplicate, appressed- 
