Geological Survey Professional Paper 160 Geologic History of the Yosemite Valley

The writer takes pleasure in expressing his appreciation to his colleague, Frank C. Calkins, for his whole-hearted collaboration in the field and for his numerous contributions to this paper. All statements relating to the petrographic character, areal distribution, and genetic relationships of the rocks are based on Mr. Calkins's findings. To Dr. Ralph W. Chaney, of the Carnegie Institution of Washington, the writer is indebted for the identification of significant plant remains from the Table Mountain district. To the officials of the National Park Service, in particular to Mr. W. B. Lewis, who was superintendent of the Yosemite National Park from 1916 to 1927, he desires to convey his gratitude for many courtesies and for effective cooperation in expediting the prosecution of the field work.