Potentilla alaskana Rydb.

Potentilla alaskana Rydberg, sp. nov
Perennial, with a thick cespitose rootstock ; stem 2-5 dm. high, silky with appressed hairs; petioles of the basal leaves 1-1.5 dm. long; leaves digitately 7-foliolate; leaflets obovate, the middle one 2.5-6 cm. long, coarsely toothed %~% to the midrib with lanceolate or ovate-lanceolate teeth, dark-green and glabrate above, white-torn en tose beneath ; stem-leaves few, 3-5-foliolate, rather small ; stipules large, ovate-lanceolate, the upper often 2 cm. long, entire or slightly toothed ; inflorescence open and corymbiform, flat-topped ; hypanthium silky with long spreading hairs ; bractlets narrowly linear, 4-5 mm. long ; sepals about 8 mm. long, ovate, acuminate ; petals broadly obcordate, 9-14 mm. long and fully as broad; stamens 20-25; pistils many; styles filiform.
Type collected on Kadiak Island, Alaska, in 1900, P. A. Walpole 1201 (U. S. Nat. Herb. no. 378183) .
Distribution : Island of Kadiak.