﻿NO. II 



SMITHSONIAN EXPEDITIONS, I9IO-I9II 



43 



had not been favorable for the presence and preservation of examples 

 of much of the life which, from what was known of older faunas and 

 the advanced stage of development of the Upper Cambrian fauna, 

 must have existed in the Middle Cambrian seas. During the season of 

 1909, the finding of a block of fossiliferous siliceous shale which had 

 been brought down by a snowslide on the slope between Mount Field 

 and Mount Wapta, led the secretary to make a thorough examination 

 of the section above it in 19 10. Every layer of limestone and shale 

 was examined, until the fossil-bearing band was finally located. After 



Fig. 47. — View looking out of a glacial cirque in the Van Home Range, 

 British Columbia. These abandoned cirques are very common in the Canadian 

 Rockies where they are frequently occupied by shallow lakes and snow banks, 

 like those in the immediate foreground. Photograph by Burling. 



that, for 30 days the shale was quarried, slid down the mountain side 

 in blocks to a trail, whence it was transported to camp on pack horses, 

 where the shale was split, trimmed, and packed and then taken down 

 to the railway station at Field, 3,000 feet below. 



A number of sections of the Cambrian rocks were studied and 

 measured in the mountains north and south of Laggan, Alberta, and 

 many beautiful panoramic photographs secured. 



