MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY | 
whole plant is covered with yellowish villous hairs besides the tomentum. Lehmann 
was in some doubt whether he should regard it as a variety of P. nivea or as a distinct 
species. He made it a species on the authority of Vahl, who knew the plant in its native 
habitat. Seeing only P. nivea and P. Vahliana nobody would hesitate in assigning 
specific rank to the latter. The trouble arises when one is to draw the line between 
either and P. wiiflora. Lehmann states that P. Vahliana was collected by Richardson in 
Captain Franklin’s journey. Specimens collected by Richardson and named P. Vahliana 
are in the Torrey Herbarium at Columbia, but these belong to P. wniflora. There is, 
however, from the same collector one specimen, a very small one, indeed, which without 
any doubt belongs to P. Vahliana, but this is, together with two specimens of P. nana, 
under the name P. nivea arctica. Except this specimen and one from Herald Island, all 
specimens seen are from Greenland and the islands of Hudson and Baffin Bay. They 
are generally labelled P. pulchella. The latter species is easily distinguished. by its small 
flowers, the petals scarcely exceeding the sepals, and its deeply dissected leayes which 
are pinnate with two approximate pairs of leaflets. 
Greenland: Dr.'H. E. Wetherill, Nos. 70 and 82, 1894; No. 174, 1894; Vahl; Rink; 
L. Krumlein, 1877-8; William E. Meehan, No. 19, 1892; W. H. Burk, No. 21, 1891.’ 
Herschell Island: Rev. J. D. Stringer, 1893. 
Arctic Coast of North America: Richardson. 
Hudson Bay: J. W. Tyrrell, No. 7254, 1893 (Marble Island). 
Herald Island: Capt. C. L. Hooper, 1881. 
$15. MULTIFIDAE. 
72. Potentilla Sommerfeltii Lehm. 
Potentilla Sommerfeltii Lehm. Del. Sem. Hort. Bot. Hamb. 1849: 6. 1849. 
Lehm. Stirp. Pug. 9: 4; Rev. Pot. 37; Walp. Ann. 2: 474; Lange, Consp. FI. 
Groen. 4; Rydberg, Bull. Torr. Bot. Club, 23: 265. 
Inmustrarions : Lehm. Rev. Pot. pl. 10, f. 2. Puare 35, f. 1; pistil, f. 2. 
Cespitose ; caudex covered with the brown scarious broadly ovate stipules. Stem 3- 
5 em. high, slightly silky, scapose, 1-2-flowered. Leaves pinnate, of two pairs of leaflets, 
and a stalked terminal one, glabrate above, finely tomentose beneath ; leaflets obovate 
in outline, divided to near the middle into linear-oblong obtuse segments. Bractlets 
oblong, obtuse, much shorter than the similar sepals. Petals obovate-cuneate, a little 
exceeding the sepals. 
1 Several other specimens are cited by Lange and Rosenyinge. 
