; infraclass Eutheria, cohort Unguiculata)
An order which comprises the family Cynocephalidae and a number of extinct forms. They are herbivores possessing a patagium, and are the most highly developed of all mammalian gliding forms. There is controversy about their relationships—whether they are related to bats (perhaps especially to Megachiroptera), or to Primates, or are isolated among mammals. The fossil record for the group is poor, but what seem to have been early representatives are known from the late Palaeocene and lower Eocene of N. America.
Subjects: Zoology and Animal Sciences.