In the _PERISSODACTYLA_ the pes like the manus is symmetrical about a line drawn through the third digit; this line when continued passes through the external cuneiform, navicular and astragalus. The astragalus has its distal portion abruptly truncated, and the facet by which it articulates with the cuboid is much smaller than that by which it articulates with the navicular. The calcaneum does not articulate with the fibula. The tarsus in _Macrauchenia_ like the carpus differs from that of other Perissodactyles and resembles that of Subungulates in having the bones arranged in lines with little or no interlocking. The calcaneum resembles that of Artiodactyles in having a small facet for articulation with the fibula. _Tapirus_ (fig. 110, A), _Rhinoceros_ (fig. 110, B) and _Titanotherium_ have a short and broad foot with the usual tarsal bones and three well-developed digits,--a number never exceeded by any Perissodactyle. From this tridactylate limb a series of stages is exhibited by various extinct forms leading gradually to the condition met with in the Horse (fig. 110, D) in which the third toe is greatly developed, while the second and fourth are reduced to slender metatarsals attached to the proximal half of the third metatarsal. In _Chalicotherium_ and _Agriochoerus_ the pes has the same abnormal characters as the manus, the digits being clawed and the ungual phalanges in _Chalicotherium_ deeply cleft. In the SUBUNGULATA the pes is sometimes plantigrade and pentedactylate, the cuboid sometimes does not articulate with the astragalus, and the tarsal bones sometimes do not interlock. In _Typotherium_ (_TOXODONTIA_) the hallux is absent and the other four digits are well developed; in _Toxodon_ and _Nesodon_ the pes is tridactylate. The tarsal bones have the regular Subungulate arrangement, the cuboid not articulating with the astragalus. The calcaneum articulates with the fibula as in Artiodactyles. The astragalus in most forms, but not in _Astrapotherium_, resembles that of the Ungulata vera in having a grooved proximal surface. In _Phenacodus_ (_CONDYLARTHRA_) the tarsus is very little modified, five digits are present, the first and fifth being small and not reaching the ground. In _Procavia_ only the three middle digits are present with a vestige of the fifth metacarpal. In the _AMBLYPODA_ the pes (fig. 108) is very short and broad, all five digits are functional, and at any rate in _Coryphodon_ plantigrade, the hallux being the smallest. The astragalus is very flat, and the tarsals interlock to a slight extent, the cuboid articulating with both calcaneum and astragalus. The pes in the _PROBOSCIDEA_ much resembles that in the Amblypoda, but differs in that the astragalus does not articulate with the cuboid, the tarsals not interlocking at all.