328 minnesota botanical studies 



2. The Flora of the Limestone Ledges of the Cougar Valley 



The Cougar valley lies just west of the main Selkirk divide, and 

 just north of the main line of the Canadian Pacific railway, enter- 

 ing the Illecillewaet valley about 6 km. northwest of Glacier. The 

 slopes of Cougar mountain, lying west of the valley, are composed 

 of crystalline limestone, and at about 1,800 m. (6,000 ft.) altitude 

 there are exposed and rather dry^ ledges of this rock. Table IV is 

 a list of the plants collected or noted upon these ledges during two 

 visits to them. It is probably not exhaustive. Notes of distribu- 

 tion are given for each species as in Table III, except where they 

 have already been given. 



table* IV. PLANTS OF THE LIMESTONE LEDGES OF THE COUGAR VALLEY 



Abies lasiocarpa (Hook.) Nutt. Abundant in both Selkirks and Rockies. 

 Anemone parviflora Michx. Revelstoke ; valley of Palmer creek below the Sir 



Sandford glacier ; upper Beaver valley ; Rockies, abundant. 

 Anemone multifida Poir. 

 Arabis Lyallii S. Wats. Widespread, but very local in its occurrence in the 



Selkirks, about one-half the specimens recorded as on limestone; Rockies, 



common. 

 Arenaria sajanensis Willd. Donkin Pass (talcose schist) ; Mt. Cheops; "small 



peak;" Rockies, not very abundant. 

 Asplenium viride Huds. South moraine, Sir Sandford glacier; head of 



Dow^nie creek; "51° 30' N. Lat. ;" Rockies, frequent. 

 Cassiope mertensiana (Bong.) G. Don. Less abundant here than elsewhere 



in the region, common in both Selkirks and Rockies. 

 Cystopteris fragilis (L.) Bernh. Frequent in Selkirks but local, very common 



in Rockies. 

 Draba crassifolia Graham. Glacier Circle; slopes west of Silvertip neve, Mt. 



Sir Sandford region (soil not calcareous) ; "small peak^;" Rockies; pres- 

 ent, but apparently not abundant. 

 Draba deflexa Greene. Avalanche Crest, Glacier; slopes west of Silvertip 



neve, Mt. Sir Sandford region ; Rockies, abundant. 

 Draba deflexa Greene var, yellowstonensis (A. Nelson) Gilg. Glacier Circle; 



north moraine, Sir Sandford glacier; Rockies, abundant. 

 Draba nivalis Liljb. 

 Epilobium angustifolium L. Very abundant throughout the Selkirks and 



Rockies. 

 Epilobium Hornemannii Reichb. 



Epilobium latifolium L. Abundant throughout both ranges. 

 Erythronium grandiflorum Pursh. Abundant but local in both ranges. 



1 Only edaiphJcally dry; the valley has the reputation of being the rainiest in the 

 vicinity of Glacier. The ledges may be actually dry during two or three weeks in the 

 course of a summer. 



2 Shaw collection No. 1051, distributed as D. nivalis. 



