The Therapsids

Abstract

The reign of the pelycosaurs was over before the middle of the Permian, with only a few rather obscure members of the group surviving into late Permian times (Table 1.2). In the Middle Permian they were replaced as the dominant land animals by the members of the Order Therapsida. The latter are classified as an order of reptiles within the sub-class Synapsida, but equate much more closely with a sub-class of the Mammalia, say the Eutheria or placental mammals, than with any individual order of mammals.