ON THE SCALOPOSAURID SKULL OF OLIVIERIA PARRINGTONI, BRINK WITH A NOTE ON THE ORIGIN OF HAIR

Oiivieria parringtoni was described by Brink in 1965 as a new genus and species. It stands closest, among the scaloposaurids, to Ictidosuchops intermedius (Broom). In general shape and size, their skulls are virtually indistinguishable from one another, but Olivieria comes from the top of the Lystrosaurus-zone (early Triassic) while the type-locality of I. intermedius is the Cistecephalus-zone (Upper Permian). Differences in dentition and differences in detailed skull moulding had argued for the creation of the new genus. The writer undertook an examination of the type specimen of Olivieria because it seemed well suited to a study of the sensory nerve supply of the muzzle. Ever since Watson (1931) suggested that one might gauge the sensitivity, suppleness and therefore the possible hairiness of the muzzle by studying the size, numbers and position of the sensory nerve foramina in the fossil skull, it has seemed likely to point, albeit indirectly, to the origin of hair in the pre-mammalian stem. Such an abundance of nerves supplying the muzzle in scaloposaurid and bauriamorph reptiles would hardly be needed for scaly and inelastic cheeks