Perissodactyla

Century Dictionary and Cyclopedia

1. A suborder of Ungulata containing the odd-toed hoofed quadrupeds: distinguished from Artiodactyla. The digits are unpaired or unequal, the third being the largest and sometimes the only functional one; and there are corresponding modifications of the metacarpal and metatarsal and of the carpal and tarsal bones and their articulations. The hind feet are always odd-toed, and though the fore feet may have 4 digits, as in the tapir, these are uneven. The astragalus has two very unequal facets or articular surfaces on the under side. The femur has a third trochanter. The dorsolumbar vertebræ are no fewer than 22 in number. The intermaxillary bones are tectiform above and united toward the symphysis, and their incisors, when present, are implanted nearly vertically and are nearly parallel to their roots. The stomach is simple and non-ruminant; there is a capacious saccnlated cæcum. In all the living forms horns, when present, are single and median, or two, one behind the other. The only living representatives of the suborder are the tapirs, rhinoceroses, and horses, including asses, zebras, etc., of the three families Tapiridæ, Rhinocerotidæ, and Equidæ. The fossil families are more numerous, including the Anchitheriidæ, Palæotheriidæ, and Lophiodontidæ. Also Perissodactyli. See also cut under solidungulate.

Wiktionary

1. n. A taxonomic order within the superorder Laurasiatheria — the odd-toed ungulates.

GNU Webster's 1913

1. n. (Zoöl.) A division of ungulate mammals, including those that have an odd number of toes, as the horse, tapir, and rhinoceros; -- opposed to Artiodactyla.

WordNet 3.0

1. n. nonruminant ungulates: horses; tapirs; rhinoceros; extinct forms