MUSEUM OF COMPARATIVE ZOOLOGY. 15 



The field work of the year consisted of : a study of the geological 

 conditions faced by the engineers engaged in cutting the five-mile 

 tunnel on the Canadian Pacific Railway at Rogers Pass in the 

 Selkirk Mountains; work on the geology about Butte and Helena, 

 Montana ; and briefer studies in the Crater Lake National Park, 

 in the Yosemite Valley, and elsewhere in the Cordillera. 





