138 GEOLOGICAL SURVEY OF CANADA. 



On limestone rocks near Stuart Lake, and at Cache Creek, B.C. 

 (Macoun.~) 



(632.) P. effusa, Dougl. 



On elevated grounds of the Assiniboine, and the higher parts of the 

 Red Eiver, plentiful. {Douglas.} Very common on the Souris Plain, 

 but seems to merge into the preceding species farther to the west. 

 (Macoun.) 



(633.) P. Plattensis, Nutt. 



P. sericea, var. p, PL Bourgeau, 256. 



Very common from Cut Arm Creek, N.W.T., westward, and south- 

 ward towards the 49th parallel on saline, marshy soils. (Macoun.) 

 Saskatchewan Plains. (Bourgeau.) 



(634.) P. dissecta, Pursh. Hook. Fl. I., 193. 



P. diversifolia, Hook. Fl. I., 190. Macoun's Cat, No. 548. 

 P. Drummondii, Hook. Fl. I., 189. Macoun's Cat., No. 556. 

 P. rubricaulis, Hook. Fl. I., 191. 



York Factory and Echimamish River. (R. Bell.*) Near Hudson's 

 Bay. (Pursh.) About Bear Lake, in Lat. 66. (Richardson.} Alpine 

 woods and prairies in the Rocky Mountains, as well as on the higher 

 summits, Lat. 52-56. (Drummond.) Rocky Mountains in the S. 

 Kootanie Pass, and on the Coast Range, B.C. (Dawson.) Great Slave 

 Lake. (Me Gill Coll. Herb. ) 



(635.) P. gracilis, Dougl. Hook. Fl. I., 1.92. 

 P. nivea, var. PI. Bourgeau, 256. 



Common throughout the western prairies and extending into British 

 Columbia. 



Var. flabelliformis, Torr. & Gray. 



P. flabelliformis, Hook. Fl. I., 192. Macoun's Cat., 549. 



Plains of the Saskatchewan. (Drummond..') Abundant on the 

 western prairies. (Macoun.) 



Var. fastigiata, Watson. 



P. fastigiata, Nutt. Torr. & Gray, Fl. I., 440. 



Old Wives Lakes, N.W.T., and westward, rare. (Macoun.) 



Var. rigida, Watson. 



P. chrysantha, Hook. Fl. I., 193. 



P. rigida, Nutt. Torr. & Gray, Fl. 1, 440. 



P. Nuttallii, Lehm. Macoun's Cat., No. 554. 



Moist prairies near the Rocky Mountains. (Drummond.) In low 



