12 



no. 2699, 1882; 1892; E. A. Mearns, no. 50, 1887; T. E. Wilcox. 

 1893. Nezv Mexico: H. H. Rusby, no. 128, 1881. 



The Argentinae are a natural group, perhaps worth generic rank. 

 The plant is propagated by true runners as in Fragaria. The 

 style is lateral as in that genus and the achene large with thick 

 corky shell. These characters are not found in any other species 

 oiPotejitilla, at least not in America. All the species belonging here 

 have pinnate leaves more or less white silky, at least beneath. The 

 species of the group are P. ajiscrinoidcs of New Zealand and the 

 following: 



POTENTILLA AnSERINA L. Sp. PI. 495. 1753- 



This well known species is found in the colder part of the 

 north temperate and the arctic zones of both hemispheres, ex- 

 tending in North America as far south as New Jersey and Ne- 

 braska, and in the mountams to New Mexico. The following 

 varieties may be distinguished : 



PoTENTiLLA Anserina grandis Torr & Gray, Fl. N. Am. i : 444. 



1840. 

 A luxuriant form growing among grass, with larger, erect or 

 ascending leaves, sometimes one foot long. It is common on 

 the Pacific coast from California to Alaska, but also collected in 

 Montana, Newfoundland and Greenland. 



PoTENTiLLA Anserina concolor Ser. in DC. Prod. 2 : 582. 1825. 



It differs from the species in the leaves, which are silky white 

 on both the upper and lower surfaces. In America it is confined 

 to the Rocky Mountain Region from Mackenzie River to New 

 Mexico, California and Alaska. 



POTENTILLA Egedii Womisk. Fl. Dan. 9: fasc. 27. 5. 



Potentilla Anserina Egedii Torr. & Gray, Fl. N. Am. i : 444. 

 1840. 



Potentilla Anserina Groenlandica Tratt. Ros. Mon. 4 : no. 13. 

 1824. 



I think that this is a good species, differing from /'. Anserina 

 in the delicate habit, the deeper and more open incisions of the leaf- 

 lets and the scant pubescence. In the specimens examined by me 

 the achenes were also different in shape. In P. Egedii they were 



