[162] Eohippus.
[163] Xiphodon.
[164] See picture heading.
[165] See picture heading.
[166] See [p. 213], and picture heading, [p. 209].
[167] The genealogy of the horse is so important, that it may be well to give a table of the seven principal stages, though transitions are known even between these.
| Period. | In America. | Front Toes. | Hind Toes. | No. of Teeth. | In Europe. | |
| 7. | Recent and Upper Pliocene | -- Equus | 1 --------- 2 splints | 1 --------- 2 splints | 40 | Equus. Equus. |
| 6. | Upper Pliocene | Pliohippus | 1 --------- 2 splints | 1 --------- 2 splints | 42 | -- |
| 5. | Lower Pliocene | Protohippus | 1 large -------- 2 small | 1 large --------- 2 small | 44 | Hipparion. |
| 4. | Upper Miocene | Miohippus | 3 | 3 | 44 | Anchitherium. |
| 3. | Lower Miocene | Mesohippus | 3 -------- 1 splint | 3 | 44 | -- |
| 2. | Upper Eocene | Orohippus | 4 | 3 | 44 | -- |
| 1. | Lower Eocene | Eohippus | 4 -------- 1 splint | 3 | 44 | -- |
[168] See [table, above].
[169] Cameleopardalis.
[170] See heading of chapter.