﻿NO. II 



SMITHSONIAN EXPEDITIONS, I9IO-I9I I 



41 



system in this portion of the Rocky Mountains. This discovery 

 led to the study of the pre-Cambrian rocks of the Bow River Valley. 

 These were found to form a series of sandstones and shales some 

 4000 feet in thickness, that appear to have been deposited in fresh- 

 water lakes prior to the incursion of the marine waters in which the 

 great bed of conglomerate and the Cambrian rocks above were 

 deposited. 



Completing the reconnaissance survey of the Bow River area, 



Fig. 45.— (Northern end of fossil quarry in Middle Cambrian Burgess shale 

 about 700 feet above Burgess Pass trail on ridge between ,Mount Wapta and 

 Mount Field, about 8 miles from Field, British Columbia. Photograph by 

 Walcott. 



•camp was moved to the Yoho River Canyon. In this canyon, one 

 of the most picturesque and instructive areas in the great Yoho 

 National Park of Canada, a study was made of the north side of 

 the President Range and numerous pictures were taken in that vi- 

 cinity, as well as from Burgess Pass, north of P'ield. 



A most interesting discovery of unique Cambrian fossils was made 

 near Burgess Pass and a number of specimens collected before the 

 snow drove the party back to Field. Three days were then spent on 

 Mount Stephen, at the famous trilobite beds, before breaking up 

 •camp on September 8, 1909. 



