Lagomorpha

The lagomorphs, order Lagomorpha, are an order of mammals of which there are two families, Leporidae (hares and rabbits), and Ochotonidae (pikas).

Though members of order Lagomorpha can resemble rodents (order Rodentia), and were classified as a superfamily in that order until the early twentieth century, they have since been considered a separate order. For a time it was common to consider the lagomorphs only distant relatives of the rodents, to whom they merely bore a superficial resemblance.

Characteristics
Lagomorphs (loģ o-moŕ fs)(Gr. lagos, hare: + morphē, form) differ from rodents in that:
 * they have four incisors in the upper jaw (not two, as in the Rodentia);
 * they are almost wholly herbivorous (unlike rodents, many of which will eat both meat and vegetation; the few recorded exceptions within the Lagomorpha occur among members of both Lepus and Ochotona, and involve the occasional foraging for carrion as a supplementary winter food source);
 * the male's scrotum is in front of the penis (unlike rodents, which is behind); and
 * the penis contains no bone (baculum), unlike in rodents.

However, they resemble rodents in that their teeth grow throughout their life, thus necessitating constant chewing to keep them from growing too long.

Classification

 * ORDER LAGOMORPHA
 * Family Ochotonidae: pikas
 * Genus Ochotona
 * Family †Prolagidae: Sardinian Pika and other related extinct pikas
 * Genus †Prolagus
 * Family Leporidae: rabbits and hares
 * Genus Brachylagus
 * Genus Bunolagus
 * Genus Caprolagus
 * Genus Lepus
 * Genus Nesolagus
 * Genus Oryctolagus
 * Genus Pentalagus
 * Genus Poelagus
 * Genus ''Pronolagus
 * Genus Romerolagus
 * Genus Sylvilagus