Volume 24 1981

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Hovasaurus boulei, an aquatic eosuchian from the Upper Permian of Madagascar
(Bernard Price Institute for Palaeontological Research, 1981) Currie, P. J.
Hovasaurus is the most specialized of four known genera of tangasaurid eosuchians, and is the most common vertebrate recovered from the Lower Sakamena Formation (Upper Permian, Dzulfian Standard Stage) of Madagascar. The tail is more than double the snout-vent length, and would have been used as a powerful swimming appendage. Ribs are pachyostotic in large animals. The pectoral girdle is low, but massively developed ventrally. The front limb would have been used for swimming and for direction control when swimming. Copious amounts of pebbles were swallowed for ballast. The hind limbs would have been efficient for terrestrial locomotion at maturity. The presence of long growth series for Hovasaurus and the more terrestrial tangasaurid Thadeosaurus presents a unique opportunity to study differences in growth strategies in two closely related Permian genera. At birth , the limbs were relatively much shorter in Hovasaurus, but because of differences in growth rates, the limbs of Thadeosaurus are relatively shorter at maturity. It is suggested that immature specimens of Hovasaurus spent most of their time in the water, whereas adults spent more time on land for mating, laying eggs and/or range dispersal. Specilizations in the vertebrae and carpus indicate close relationship between Youngina and the tangasaurids, but eliminate tangasaurids from consideration as ancestors of other aquatic eosuchians, archosaurs or sauropterygians.
A protosuchid crocodilian from the Forest Sandstone Formation (Upper Karoo) of Zimbabwe
(Bernard Price Institute for Palaeontological Research, 1981) Raath, M. A.
A protosuchid crocodilian is reported from the Forest Sandstone Formation (Upper Triassic) of the central Zambezi Valley, Zimbabwe. It is closely related to known protosuchians from terminal Karoo deposits in South Africa and it is provisionally referred to cf. Notochampsa sp.
Palaeontologia africana Volume 24
(Bernard Price Institute for Palaeontological Research, 1981)
Fossil hyaenidae from the Makapansgat Limeworks deposit, South Africa
(Bernard Price Institute for Palaeontological Research, 1981) Randall, R. M.
The remains of three hyaena species have been recovered from the Makapansgat Limeworks deposit. A common small form , Hyaena hyaena makapani, and a rare large form, Pachycrocuta brevirostris, were recovered from Member 3 (Lower Phase 1 grey breccia). The rare Crocuta crocuta was recovered from Member 4 (Upper Phase 1 breccia), and was the only hyaena from this horizon. Abundant cranial and dental material of H. h. makapani facilitated comparisons with extant and fossil forms to confirm its identification as a subspecies of the extant striped hyaena. Despite morphological differences in the skull and teeth, H. abronia from Langebaanweg is confirmed as its likely ancestor. Some deciduous teeth of H. h. makapani are described and the eruption sequence of permanent cheek teeth deduced. P. brevirostris appears to be the largest fossil hyaena from Africa, showing affinities to P. bellax from Kromdraai. C. crocuta is similar to the extant form and the fossil forms from East Africa. As in the East African deposits, C. crocuta appears relatively late in the succession. The hyaena material has limited value in site faunal correlations for dating purposes, but does not contradict the palaeomagnetic age estimate of more than 2,9 My for Member 3 (grey breccia) (Partridge 1979).
Revised stratigraphy of the Beaufort Group in the southern Karoo Basin
(Bernard Price Institute for Palaeontological Research, 1981) Turner, B. R.
The Beaufort Group in the southern Karoo Basin between Graaff-Reinet and Sutherland has been divided into three formations based primarily on the changing ratio of sandstone to mudstone. The former Abrahamskraal Formation is elevated to subgroup status and divided into two new formations, the Lootskloof Formation and the Verlatenkloof Formation, whilst the Teekloof Formation is retained but more precisely defined. The Verlatenkloof Formation includes two members, the Jakhals Valley Member and the Paalhuis Member. The Teekloof Formation includes the Oukloof Member in addition to the previously defined and described Oudeberg Sandstone Member. Stratotypes are erected for the new formations and members in accordance with the recommendations of the South African Committee for Stratigraphy. Subdivision of the formations and their relationship to the established biostratigraphy and facies patterns provides a means of fixing and correlating the most important uranium mineralised units in the succession with greater accuracy. These comprise the Paalhuis Member, the Oukloof Member and the Jakhals Valley Member, although the most important mineralised unit is the Paalhuis Member which contains up to 90 per cent of all known uranium occurrences in the Beaufort West area.
Presidential address: taphonomy as an aid to African palaeontology
(Bernard Price Institute for Palaeontological Research, 1981) Brain, C. K.
Palaeontology has its roots in both the earth and life sciences. Its usefulness to geology comes from the light which the understanding of fossils may throw on the stratigraphic relationships of sediments, or the presence of economic deposits such as coal or oil. In biology, the study of fossils has the same objectives as does the study of living animals or plants and such objectives are generally reached in a series of steps which may be set out as follows.