{198} Of the land animals which then inhabited the earth, might be mentioned the _Dinotherium_. From the remains of it which still exist it must have measured not less than sixteen feet high and twenty-four feet long with a head at least three feet in breadth and hence capable of containing a brain large enough for the most exacting phrenologist. Then again there was another huge animal called the _Mastodon_. We may get some idea of the enormous size of the animal from the fact that the remains of some of its grinding teeth, recently found in Pennsylvania, weighed no less than seventeen pounds. There existed at that time still another huge animal whose remains are found in Siberia, Sweden, Italy and North and South America. It is commonly called a Mammoth, {199} though on account of its resemblance to existing elephants, naturalists have named it _Elephas Primigenius_. It was covered with three kinds of hair: first strong bristles, secondly, soft hair, and thirdly with reddish wool growing among the hair. Geologists agree that during the latter part of this period the earth began to assume conditions similar to those which prevail at the present time. This is indicated by the abundance of deciduous plants (that is plants that drop their leaves each autumn), which are to be found in North America. It is thus evident that the climate was becoming cooler, the dense atmosphere which so long had wrapped the earth as with a mantle had dissipated; the carbonic acid and other poisonous gases, which were totally unfit to support animal life had been absorbed by the rank vegetation of the coal period. Geologists tell us that this was the period when the Wasatch and Uintah mountains were formed and the center of the western continent upheaved, by which the great interior sea which previously divided America into two continents was abolished. The change of physical geography was enormous and the change of climate was doubtless correspondingly great. It was natural, therefore, to expect, with the opening of the next era, a very great change both in plant and animal life. So ended the fifth epoch of creation, for "The evening and the morning were the fifth day." Moses opens the record of the sixth epoch by the words, "And God said, Let the earth bring {200} forth the living creature, after his kind, cattle, and creeping thing, and beast of the earth after his kind; and it was so." Geology confirms this by declaring, as it were, that then her modern history commenced. Then began the present aspect of field and forest; and modern types of animals were introduced and became predominant. Many of the species of both plants and animals were identical with those still living. Further, one of the most noteworthy facts connected with the first mammals (or milk-giving animals), is the suddenness of their appearance in great numbers, and of all, or nearly all orders, even the highest, except man.