Limitation of the Statement.—Evidences bearing upon the interval between the glacial epochs may be drawn from various parts of the glaciated field, and from the various phenomena connected with glaciation. It is not, however, my purpose to make any approach to an exhaustive review of these evidences, or even to touch upon the arguments that may be drawn from all the several sources. I desire simply to bring to your attention certain specific evidences that have an important bearing upon the length of the main interglacial interval, and that lend themselves more readily than others to intellectual estimation. The evidences that are especially additional to previous knowledge are drawn from the lower Mississippi valley; but, in connection with these, I shall briefly refer to evidences drawn from other valleys that fall into marked harmony with them.
The Evidence drawn from the Lower Mississippi.—In the lower Mississippi valley the . . .