Zapodidae (jumping mice; order Rodentia, suborder Myomorpha) A family of mouse-like rodents in which the hind limbs are more or less elongated, permitting saltatorial movement, and the tail is long and used for balancing. The cheek teeth are either brachydont or semi- hypsodont. Cheek pouches are present. They are distributed widely throughout the temperate northern hemisphere. There are four genera, with 11 species.

Dipodidae(jerboas; order Rodentia, suborder Myomorpha) A family of nocturnal or crepuscular saltatory rodents in which the hind limbs are much elongated, the tail is long with a tuft at the tip, and in most species the eyes and ears are large. Apart from the specialization of their limbs, dipodids are rather primitive. They are distributed throughout arid and desert regions of the Old World. There are 10 genera, with about 27 species.