152 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 



Bot. Cal. 1: 183; Eothrock in Wheeler's Exp. 6: 114; Rattan, An. Key W. Coast 

 Bot. 52. 



Potentilla Gordonii Greene, Pittonia, 1 : 106. 1887. 



Greene, Fl. Fran. 1 : 69. 



Illustrations: Hook. Journ. Bot. 5: pi. 12. Plate 92, f. 7 ; dissection of flower, 

 /. S; pistil, /. 9; stamen, /. 10; fruiting hypanthium and calyx, /. 11. 



Root thick and deep. Caudex woody, branched, cespitose, covered with the re- 

 mains of old leaves. Stem subscapose, minutely glandular-puberulent or glabrous, 1-2 

 dm. high, seldom 3 dm. Basal leaves numerous, finely puberulent or glabrate, pinnate ; 

 leaflets 10-20 rather approximate pairs, 5-12 mm. long, divided into 3-5 segments or 

 again divided. Segments broadly oblong to linear. Stem leaves, if any, very small. 

 Cyme capitate. Hypanthium campanula te, 3-4 mm. in diameter, villous-puberulent 

 and somewhat glandular, yellowish ; bractlets linear, about half the length of the ovate 

 sepals. Petals yellow, spatulate or oblanceolate, shorter than the sepals. Stamens 5. 

 Pistils generally 1-3, sometimes more. 



It is a very variable species and the most common in the genus, extending from 

 Wyoming to Montana, Washington and central California. It difiers from all the mem- 

 bers of the group in its deeper campanulate hypanthium. 



Horkelia Gordonii alpicola, 



Ivemx alpicola Rydberg ; Howell, Fl. N. W. Am. 1 : 182. 1898. 

 More cespitose and more glandular, stems less than 1 cm. high ; leaflets shorter. 

 This plant much resembles I. pygmaea in habit, but lacks the bristle-points of the 

 leaves and has always 5 stamens. 



About the same range as the species, but generally grows at greater altitudes. 



Horkelia Gordonii megalopetala. 



Petals large, obcordate, much exceeding the sepals ; hypanthium less deep. 

 Resembles a low plant of H. Gordonii, but differs in the characters given. It may 

 be a good species, but the material known is insufficient. 



California : Bolander (Mt. Dana, type in Herb. Cahf Acad. Sci.). 



44. Horkelia pygmaea (Gray). 



Iveiiia pygmaea Gray, Proc. Am. Acad. 6: 531. 1865. 



Wats. King's Rep. 5 : 448. 



Ire.^-ia Gordonii var. pygmaea AVats. Bot. Cal. 1 : 183. 1876. 



