MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 107 
Potentilla diversifolia var. pinnatisecta Wats. King’s Rep. 5: 87. Imgpart Lert: 
Potentilla ovina J. M. Macoun, Can. Ree. Sci. 6: 464. 1895. 
Inntusrrations: Pare 46, f. 1; dissection of flower, f. 2; pistil, f 3; stamen, f- 4; 
fruiting hypanthium and calyx, f. 5. 
Subcespitose. Stems mostly erect, less than 1 dm. high, strigose, with 2 or 38 re- 
duced leaves, 3-6-flowered. Stipules smaller than in P. Plattensis, ovate, lanceolate, acute. 
Basal leaves crowded, 2-4 em. long, hoary, especially when young, pinnate with many 
crowded leaflets; leaflets deeply cleft into oblong obtuse lobes. Hypanthium hirsute, in 
fruit about 8 mm. in diameter and erect; bractlets and sepals lanceolate, acute, the 
former shorter. Corolla about 1 em. in diameter. Petals obeordate, about a third longer 
than the sepals. 
The specimens from which P. diversifolia pinnatisecta were described, viz. : Watson’s 
Nos. 331 and 332 of the King Expedition illustrate, I think, not less than three different 
species. In the Gray Herbarium, No 331 is represented, as it seems, by a typical P. Plat- 
tensis. ‘This is doubtless the reason why Watson afterwards transferred the var. pinnati- 
secta to that species. No. 332, which Watson, in King’s Report, characterizes as an al- 
pine more hairy form, is there represented by a specimen of what James Macoun 
describes as P. ovina. This may be regarded as the typical P. pinnatisecta, as the other 
forms of the collection are already named. In the Columbia Herbarium, No. 331 is rep- 
resented by an unusually large form of P. pinnatisecta (P. ovina Macoun) and No. 532 
by a depauperate specimen of P. Breweri var. expansa Wats. 
The main differences between P. Plattensis and P. pinnatisecta are well pointed out by 
Professor Nelson, /. ¢., only that his characterizing of P. Plattensis refers rather to the 
most common, more prostrate form with narrow segments, mentioned below, and that 
his specimens representing P. pinnatisecta are unusually large, less hairy and with longer 
segments than usual. The typical form is subcespitose, seldom over 1 dm. high, with 
nearly leafless flowering stems, smaller stipules than in P. Plattensis, and a densely hoary 
pubescence, especially when young. It ranges from Colorado and Utah to British 
America, and is a strictly alpine plant. Specimens examined: 
Colorado: C. 8. Crandall, 1891; Osterhout, No. 7, 1897. 
Wyoming: F. H. Burglehaus, 1893; F. Tweedy; J. N. Rose, No. 385, 1898; C. ©. 
Parry, No. 97, 1873; Aven Nelson, No. 1819, 1895. 
Utah: 8. Watson (King’s Exp.) Nos. 331 and 332 (in part). 
Montana: W. M. Canby, No. 101, 1883; R. 8. Williams, No. 753, 1888; Flodman, 
Nos. 549, 550 and 551, 1896. 
British America: John Macoun, 1885. 
