Page:Origin of the High Terrace Deposits of the Monongahela River.pdf/3

370 We thus have at hand an explanation of the immense deposits of stratified silts, clays, boulder beds, and other trash found at the junction of streams all along the Monongahela river, and especially above the level of the upper slopes of the river gorge, beginning at one hundred to one hundred and fifty feet above the present river.

A large stream, Decker's creek, joins the Monongahela at Morgantown, coming in from the east after cutting through Chestnut ridge and draining a large mountain area east from the latter. At its junction with the Monongahela it has dumped large deposits of sand, boulders, and clay, which after much erosion still retain, in favorable localities, a depth of seventy feet. From this fact, and also because these deposits were first studied there, I have named them the Morgantown beds, confining the name to the deposits which rest on the pre- glacial rock-floor of the river. These beds, which are often as distinctly stratified as the under-lying Coal Measure rocks, can be found wherever any shelf of the ancient rock-floor of the river has been preserved, from the head of the Monongahela to Pittsburg, and on northwestward along the Ohio, and up the Beaver until they are met and submerged by the vast deposits of the terminal moraine. About one mile north from Morgantown, and near the Flats school-house, these beds contain beautifully preserved fossil plants imbedded in a bluish gray pottery clay of impalpable fineness. The plant bed lies at an elevation of 240 feet above the present river, or about 1,080 feet A. T.

The small collection that I made of these plants and deposited in the West Virginia University, several years ago, together with collections made at different times by Prof. S. B. Brown, of the University, and also some collected by Mr. Walter Hough, of the National Museum, were all sent to Dr. F. H. Knowlton, the accomplished paleobotanist of the U. S. National Museum, Washington, D. C., for identification. Under date of Sept. 17th, 1895, Dr. Knowlton sent me the following account of these fossils:

Report on a Collection of Fossil Plants from Morgantown, West Virginia. By F. H. Knowlton, Ph. D.

Some years ago I was informed by Dr. Walter Hough of the U. S. National Museum of the existence of finely preserved fossil leaves in the