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Vancouver Island, and in Upper Cretaceous rocks in 

 the Queen Charlotte Islands, remains of Sequoia have 

 been discovered. One of the most remarkable in- 

 stances of the preservation of trees of a bygone age 

 is supplied by the volcanic deposits of Lower Tertiary 

 age exposed on the slopes of Amethyst mountain 

 in the Yellowstone Park district. At different levels 

 in the volcanic and sedimentary material, which is 

 piled up to a height of over 2000 ft. above the valley, 

 as many as fifteen forests are represented by erect 

 and prostrate limbs of petrified trees (Fig. G). The 

 microscopical examination of some of these trees 

 has shown that they bear a striking resemblance to 

 Sequoia semiiervirens. In a photograph of these 

 petrified forests by the U.S. Geological Survey (36,2) 

 one sees living Conifers side by side with the lichen- 

 covered and weathered trunks of the fossil species 

 {Sequoia tnagiufica), living and extinct being at a 

 distance hardly distinguishable. (Frontispiece.) 



In concluding this brief survey of the fossil records 

 of Sequoia, reference may be made to the discovery 

 of petrified wood in Cretaceous rocks in South Nevada, 

 possessing the anatomical featnresof Sequoia (/igantea, 

 which shows that close to the present home of the big 

 trees their ancestors flourished during a period of the 

 earth's history too remote to be measured by human 

 reckoning. 



The distribution of the Tertiary and Cretaceous 



