forward to take the place of those which were worn out or ground away. The process was not as perfect as that in the present elephant, described in chapter first; as sometimes three teeth were in each jaw of the mastodon at the same time. The teeth are the chief points of distinction between the elephant and the mastodon; and they are readily recognized by the grinding surfaces of the molars, which have transverse ridges, their summits being divided into conical cusps, with smaller ones often clustered about them. The enamel is quite thick: the cementum, which is so plentiful in the teeth of elephants, is very scanty, never filling in the interspaces of the ridges; so that the teeth present a serrated edge. The great mastodon, many species of which are known, lived during what is known as the miocene time of geology, ranging from the middle of this period to the end of the pliocene, in the Old World, when they appear to have become extinct. In Ohio, the mastodons lived to a much later time, surviving until the late pliocene period, and were, as I have suggested, probably hunted by early man, if he was in existence at that time. The mastodons had a wide geographical range, being found in almost every country. Nine species are known from Europe,—_M. angustidens_, _M. borsoni_, _M. pentelici_, _M. pyrenaicus_, _M. taperoides_, _M. virgatidens_, _M. avernensis_, _M. dissimilis_, and _M. longirostris_. Five species have been found in India, and four in North America. Two are from South America. Two only have been found in England. Mastodons undoubtedly lived in Australia; a molar tooth of _M. andium_, or a similar form, having been found in New South Wales. From this brief review of the early proboscidians, it will be seen that the elephant, as we popularly term all proboscidians, had originally as wide a range as man, appearing in almost every country; and it is even described by Pliny as being very plentiful in the forests of the so-called Atlantis. * * * * * Equally as interesting as the huge mastodon was the pygmy elephant, two species of which formerly existed. These were remarkably diminutive creatures, about the size of ordinary sheep; while their baby elephants must have been about that of ordinary cats. We can imagine a herd of these wonderful little creatures roaming about, and the strange appearance they must have presented. Their names are _Elephas melittensis_ and _E. falconeri_; their bones are found in Malta and various parts of Italy. Living small or pygmy elephants are frequently referred to in old works. Bles, a correspondent of Buffon, states that he saw one in the Kandyan kingdom not larger than a heifer, and covered with hair. Bishop Heber says, that, in his journey from Bareilly to the Himalayas, he saw the Rájah Gourman Sing mounted on an elephant hardly bigger than a Durham ox, and almost as shaggy as a poodle.