The Anoplotheria have two characters not observed in any other animal, namely feet with two toes (see [Lign. 252]), the metacarpal and metatarsal bones of which do not unite into a single piece, as is the case in the ruminants; and teeth placed in a continued series without any interval between them (Petrif. [Lign. 111]); man alone has the teeth arranged in the same manner. I subjoin figures of molar teeth of Palæotherium and Anoplotherium ([Lign. 256]).
Lign. 256. Teeth of Palæotherium and Anoplotherium.
Upper Eocene. Isle of Wight and Montmartre.
| Fig. | 1.— | Upper molar tooth (external surface) of Palæotherium magnum. Binstead. |
| 2.— | Lower molar of Palæotherium magnum. | |
| 3.— | Grinding surface of first upper molar of Anoplotherium secundarium. Binstead. | |
| 4.— | Inner side view of right upper canine of Anoplotherium commune. | |
| 5.— | Upper molar of Anoplotherium commune. Montmartre. | |
| 6.— | Lower molar of the same animal. |
There are also sub-genera, as for example, Xiphodon and Dichobune, characterized by peculiarities of dental and osteological structure; and Anthracotherium (so named from two species having been found in a bed of Anthracite or Lignite, near Savone), a genus intermediate between the Palæotheria and Hogs. The skeletons of these remarkable animals are imbedded with the remains of carnivora, marsupialia, bats, birds, crocodiles, tortoises, and fishes.
In England, no remains of the extinct Pachydermata of the Paris Tertiary strata were discovered until a few years since, and they are still exceedingly rare. There have been found in the fresh-water limestone at Binstead, near Ryde, and at Seafield, Isle of Wight, (see Geol. I. Wight, 1854, Prefat. Note,) teeth and portions of the jaws of two species of Anoplotherium, four of Palæotherium, and one of Chæropotamus, an animal allied to the Hog Tribe (Geol. Trans. 2d ser. vol. vi. pl. iv.; and Brit. Foss. Mam. p. 413, &c.).
The Hyopotamus ([Lign. 257]) is a genus of Anthracotherioid pachyderms, two species of which have been determined by Prof. Owen (Quart. Geol. Journ. vol. iv. p. 103, &c.), from specimens of teeth found in the upper eocene of the north-west coast of the Isle of Wight, by the Marchioness of Hastings.
The Palæotherium, Dichobune, Dichodon, Paloplotherium, and others occur in the upper eocene fresh-water deposits of Hordwell Cliff (see Charlesworth’s Journal, No. 1, p. 5, and pl. ii.; Quart. Geol. Journ. vol. iv. p. 17, and pl. iii.; and Rep. Brit. Assoc. 1851, sect. p. 67).
Two species of a new genus, intermediate between the Hog and the Hyrax, named by Professor Owen Hyracotherium, have been discovered in the eocene sands at Kyson, in Suffolk, and in the London Clay of the cliffs at Studd Hill, about a mile to the west of Herne Bay.[744] The latter specimen consists of a mutilated skull, about the size of that of a Hare, with the molar teeth perfect.