THE EVOLUTION OF THE ELEPHANT
the continents except South America and Australia. In the Oligocene and Eocene epochs there were no true elephants, and the mastodons appear to have lived only in Africa.
The earliest known member of the elephant family is a tiny form, just over two feet high, whose remains have been found near the Fayum Oasis, in Egypt. It is of upper Eocene age, and is a mastodon known as Moeritherium. This primitive mastodon may have given rise to the true elephants, although its neck is short and heavy, its feet are short and compact, its head is of normal length, and it has nearly a full set of teeth. The second incisor in the upper jaw, however, is large, and the third incisor and the canine tooth are small and appear to be on their way to being lost. It also has incisors in the lower jaw, the second one large, but no third incisor or canine tooth. In each jaw there are six low-crowned grinding teeth. This form seems to have lived near rivers and ponds and to have subsisted on soft vegetation, the large upper and lower incisors suggesting that they were used to dig up bulbs and roots. Remains of mastodons in this stage of development are found only in Egyptian beds.
In the Oligocene beds, which lie just above the Eocene, the remains of another elephant-like form are found. This form which is called Palaeomastodon, has the second incisor of both the upper and lower jaws considerably enlarged. Of the other teeth, the first and third incisors and the canine of the upper jaw have disappeared, as has also the first incisor of the lower jaw; all that is left of the front teeth in either jaw is the second incisor. These incisors of the lower jaws are flattened and the jaw is elongated, so that in spite of the fact that the neck has shortened the mouth still reaches the ground. The two incisors of the upper jaws have greatly enlarged and spread to either side. Between these upper tusks lay the upper lip, prolonged enough to reach to the end
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