species of Sequoia in both Cretaceous and Tertiary rocks in Austria, Germany, Italy, France, and elsewhere, shows that the ancestors of the Californian trees were common in the European region. The exploration of Cretaceous and Tertiary rocks in Arctic Europe has revealed the former existence in Greenland, Spitzbergen, and other more or less ice-covered lands of plants which clearly denote a mild climate. Cones and branches of Sequoias have been found in abundance in Lower Tertiary beds on Disco Island off the west coast of Greenland, and similar evidence of the northern extension of the genus has been obtained from Spitzbergen. Dr Nathorst of Stockholm speaks of twigs of Sequoia in the Tertiary clays of Ellesmere Land almost as perfect as herbarium specimens. In Tertiary beds on the banks of the Mackenzie River, in Alaska, Saghalien Island and Vancouver Island, and in Upper Cretaceous rocks in the Queen Charlotte Islands, remains of Sequoia have been discovered. One of the most remarkable instances 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. 6). The microscopical examination of some of these trees has shown that they bear a striking resemblance to _Sequoia sempervirens_. 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 magnifica_), 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 features of _Sequoia gigantea_, 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.