NO. 12 



SMITHSONIAN EXPLORATIONS, I917 



The geological field-work by Secretary Walcott in the Rocky Moun- 

 tains during recent years has yielded important additions to our 



Fig. 2. — Burgess shale fossil quarry l)lasted out on the steep slope of 

 the ridge between Mount Wapta and Mount Field at 6,700 feet above 

 sea level and 8 miles by trail from Field, British Columbia. 



The fossil-bearing layers are just beneath the surface upon which the 

 men are standing. Photograph by Walcott, 1914. 



knowledge concerning the Cambrian and pre-Cambrian formations 

 and has brought to light evidences of life far earlier than heretofore 

 known. The results of much of this work in the field and subsequent 



