Drainage.— The Appalachians form the watershed between the Atlantic Ocean and the Mississippi River systems; this does not lie in one continuous line, but shifts its position from one line of ridges to another, so that many of the rivers cut their way through the moun tains from west to east, or east to west; the Delaware and Susquehanna, for example, with their branches. These two rivers, with the Po tomac and James, drain much of the eastern slope; the Ohio, with its tributaries, is the chief means of drainage on the western slope.
Flora and Fauna.— The mountain slopes are heavily wooded throughout the whole sys tem. The white pine is found in all portions; the sugar maple, the white birch, ash and beech grow on the northern mountains; the oak, cherry, white poplar, white and yellow pine farther south. On the poorer lands the ever greens flourish, such as spruce, hemlock and balsam-fir, which, on account of their dark foliage covering the summits of the Black Mountains, have given this range its name. There are large quantities of flowering shrubs, particularly the rhododendrons, azaleas and laurel often growing in almost impenetrable thickets, and many varieties of smaller plants and flowers. Panthers and wolves have prac
tically disappeared from the mountains, but bears, deer and wild-cats are quite common. Small game birds are plentiful and wild tur keys also on the southern ranges. Rattlesnakes • and copperheads are found in all parts of the Appalachians, but not in great numbers.
Bibliography.— Barrell, J. 'The Upper Devonian Delta of the Appalachian Geosyn cline> (In American Journal of Science, series 4, Vols. XXXVI and XXXVII, New Haven 1913-14) ; Guyot, 'The Appalachian Moun tain System> (American Journal of Science. series 2, Vol. XXXI) ; Hayes, 'The Mechanics of Appalachian Mountain Structure> and 'Physiography of the Chattanooga District' (Annual Report of United States Geological Survey, XIII and XIX) ; Kephart, H., 'Our Southern Neighbors) (New York 1913) ; Mor ley, M. W., 'The Carolina Mountains' (Boston 1913) ; Rogers, H. D. and W. B., 'Physical Structure of the Appalachian Chain> (Ameri can Journal of Science, series 1, Vol. XLIV) ; Stockbridge, H. E., 'A Bibliography of the Southern Appalachian and White Mountain Regions> (Washington 1911) ; Willis, B., 'The Northern Appalachians' (New York 1895).