. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 412 ANNALS OF THE SOUTH AFRICAN MUSEUM Anteosaurus. In the latter the bone extends right up to the skull roof, has an expanded waist and a relatively long anterior footplate. In Jonkeria (titano- suchid) the footplate is also extended anteriorly but dorsally the epipterygoid only reaches halfway to the roofing bones while the footplate as well as the dorsal ramus are reduced in the tapinocephalid Struthiocephalus. In none of the Dinocephalia do we find evidence of a posterior extension to the footpla
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 412 ANNALS OF THE SOUTH AFRICAN MUSEUM Anteosaurus. In the latter the bone extends right up to the skull roof, has an expanded waist and a relatively long anterior footplate. In Jonkeria (titano- suchid) the footplate is also extended anteriorly but dorsally the epipterygoid only reaches halfway to the roofing bones while the footplate as well as the dorsal ramus are reduced in the tapinocephalid Struthiocephalus. In none of the Dinocephalia do we find evidence of a posterior extension to the footplate which could have formed a link between the epipterygoid and the quadrate. According to Watson (1914) the Dinocephalia, as a group, has a very special importance because alone amongst the therapsids it retained a large quadrate. This feature as well as the absence of the quadrate ramus of the epipterygoid indicates affinities with the reptilian rather than the mammalian lines of evolution. Anomodontia The anomodonts are generally regarded to be an aberrant group of mammal-like reptiles with but weak mammalian affinities. This is borne out by the structure of the palatoquadrate complex in this group. As in the Dino- cephalia the anomodonts Kannemeyeria erithrea (Case, 1934), Dicynodon kolbei (Broom, 1932), D. sollasi (Watson, 1948), Lystrosaurus murrayi (Broom, 1932), Daptocephalus leoniceps (Ewer, 1961), Kingoria nowacki (Cox, 1959), Dicy?iodon grimbeeki and Pristerodon buffaloemis, all display an epipterygoid with a long, thin dorsally projecting columellar portion, reminiscent of recent reptiles (see later). However, in contrast to the latter the base of the epipterygoid is expanded, to varying degrees, in all of the above, extending for some distance along the upper edge of the quadrate ramus of the pterygoid. In Kannemeyeria the base extends from a point close to the quadrate to beyond the front of the interpterygoid space. In the anomodonts investigated, there is no dire
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
