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The dog of the Miocene epoch is represented in fossils indicating an animal about the size of the Newfoundland breed.

In the northeastern part of the state, and in the vicinity of Burns, Canyon City, and Prineville, various groups of important fossil shells of the Jurassic period have been found. In Baker and Crook Counties, and in the Siskiyou region of southern Oregon, the carboniferous rocks have yielded many interesting groups of fossil shells of the Paleozoic era. The trigonia, a bivalve shell of Cretaceous times, is abundant in both southern and northeastern parts of the state.

A group of marine shells of great interest to the geologist and paleontologist is that of the chambered cephalopods. Of highest rank in this group are the ammonites, which became extinct at the close of the Cretaceous period. Both the chambered nautilus and the ammonite have been found widely distributed in the rocks of the Siskiyou region. At Astoria and in the vicinity of Westport, the Columbia River, cutting into the Eocene belt, has exposed specimens of another beautiful shell fossil, the aturia.

Submerged groves of trees in the Columbia River near the Upper Cascades indicate that this river between the Cascades and The Dalles was more than twenty feet lower when these trees were living than it is today. These submerged forests are in a slow process of decay and are not "petrified," although they have been thus termed by some laymen. The upright position of the trees affords evidence that rising water covered them where they stood.

In Columbia Gorge, near Tanner Creek, were found fossil fragments of a leaf of the gingko tree, a beautiful species known previously only in sacred groves around the temples of China and Japan. Since discovery of these fragments, test plantings of gingko trees imported from Japan have been found to thrive in the vicinity of Portland. Near Goshen, on the Pacific Highway, is an assemblage of fossil leaves, entombed in fine-grained volcanic ash, resembling trees of the lower Oligocene epoch, whose counterparts now flourish in Central America and the Philippines. This evidence seems to establish unquestionably the existence of a tropical climate in the Oregon region at some remote time.

FLORA AND FAUNA

In the moist valleys, on the craggy mountains, and on the semiarid deserts of Oregon, grow a multitude of flowers, ferns, grasses, shrubs, and trees. One authority lists more than two thousand species