Of the gigantic Mammals of the Tertiary beds of the Western States, it would also be superfluous to speak; their gigantic size is known by every high school pupil, or every one who has visited any important museum in Europe or America. We may perhaps be reminded again that all the species of these "older" rocks are extinct species. I have already suggested the grave doubts on this point, regarding the great mass of the lower forms of life, plant and animal; but we will let that pass. But let us take some of the "late" Tertiary and Pleistocene mammals, which cannot be distinguished from living species, and how do we fare? It is the same old story; the moderns are degenerate dwarfs. The hippopotamus (_H. major_) is a good one to start with, for Flower and Lydekker[83] say that it "cannot be specifically distinguished from _H. amphibius_" of Africa. This gigantic brute used to live in the rivers of England and Western Europe. The text-books generally say in "Pliocene times," because, I suppose, no one has the courage to suggest that it lived under the ice of the "Glacial period." We are always pointed to the wool on the rhinoceros and the mammoth as indicating a somewhat cool climate, but the well known amphibious habits of the hippopotamus cannot be so easily disposed of. But if, as I believe, this world never saw a foot of ice at the sea level till the end of the "Pleistocene period," to speak after the current manner, the problem becomes very simple. In that case the time of the Hippopotamus in England was neither earlier nor later than that of the palms and acacias of the "early" Tertiary or Mesozoic rocks, or than that of the mammoth, lion, and hyena of the Pleistocene. There is as we now know absolutely nothing but an out-of-date hypothesis to indicate that they did not all live there together. We may, if we choose, try to dovetail those conditions into the present on the basis of uniformity and slow secular change, by assuming a few million years for the process, but there is neither a particle of evidence nor of probability that the hippopotamus was not contemporary alike with the palms of the Eocene and the elephants and lions of the post-Tertiary. As for the mammoth itself, which Flower and Lydekker have intimated may turn out identical with _E. Columbi_ and _E. armeniacus_, and thus the direct ancestor of the modern Asiatic elephant (_E. indicus_), some have argued that its average size was not greater than that of the existing species of India and Africa. But Nicholson says that it was: "... considerably larger than the largest of living elephants, the skeleton being over sixteen feet in length, exclusive of the tusks, and over nine feet in height."[84] Dana is equally positive: "The species was over twice the weight of the largest modern elephant, and nearly a third taller."[85]