82 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 
Greenland: W.H. Burk, No. 24, 1891; Wm. E. Meehan, No. 22, 1892 (Gn part, 
Upernavik), I. J. Hayes, No. 21, 1861.’ 
64. Potentilla Robbinsiana Oakes. 
Potentilla Robbinsiana Oakes; Torr. & Gray, Fl. N. Am. 1:441. Assynonym. 18388. 
Rydberg, Bull. Torr. Bot. Club, 23 : 304 ; Britt. & Brown, Ill Fl. 2: 211. 
Potentilla minima 8 Torr. & Gray, Fl. N. Am. 1: 441. 1840. Beck, Bot. Ed. 2: 99. 
Potentilla minima Walp. Rep. 2: 33, 1843; Gray, Man. Hde 1122 1848. 
Wood, Class Book, 342; Bot. & Fl. 107; Ann. 2: 505, 1852. 
Potentilla frigida Gray, Man. Ed. 2: 118, 1856; Ed. 5: 154; Wats. & Coult. in 
Gray, Man. Ed. 6: 160, 1890; Wats. Proc. Am. A rad. 8: 560. 
Potentilla minima Robbinsiana Lehm. Rev. Pot. 159. 1856. 
InLusrrations: Britt. & Brown, Ill. Fl. 2: f. 1921. Pate 32, f. 6; dissection of 
flower, f. 7; pistil, f. 8; stamen, f. 9; fruiting aoe and calyx, f. 10. 
Cestipose ; stems 2-3 cm. high, softly long-pilose, one-flowered, and with 1 or 2 
diminutive leaves. Stipules ovate, obtuse, scarious and brown. Leaves ternate, short- 
petioled, villous-pilose especially beneath; leaflets obovate, cuneate at the base, deeply 
incised serrate with generally obtuse teeth. Hypanthium villous, in fruit 5-7 mm. in 
diameter; bractlets and sepals oblong, obtuse, subequal. Petals obovate, slightly exceed- 
ing the sepals. 
Torrey and Gray placed this species as a variety under P. minima and Gray trans- 
ferred it to P. frigida. It very much resembles both of those European species. It 
comes nearest to P. minima in habit, but to P. frigida in pubescence. It differs from 
both in the small petals, which about equal the sepals, and in the bracts and the sepals, 
which are narrow and subequal. In both P. frigida and P. minima the petals are longer 
than the sepals, and these much longer than the bractlets. The same characters that 
distinguish P. Robbinsiana from the two species mentioned distinguish it also from its 
American relatives. The range of P. Robbinsiana is very limited. It apparently is con- 
fined to the White Mountains of New Hampshire, where it was first collected by Rob- 
bins and Oakes. 
Potentilla elegans Cham. & Schlecht. Linnaea, 2: 22. 1827. 
The species, as far as I know, has not yet been collected in America, but is mentioned here 
because it is quite common across Behring Strait and may be found in Alaska. It resembles P. Rob- 
binsoniana in the sepals and bracts, but is a more delicate plant, the leaflets being only 3-5 mm. long 
and nearly glabrous. 
1 Several other specimens are cited by Lange. 
