. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. A PLIOCENE URSID FROM SOUTH AFRICA 129 The M^ (L 12637) is an important specimen, since although it is incom- plete, its morphology indicates that the affinities of the Langebaanweg agrio- theriine lie with Agriotherium rather than Indarctos. It consists of a paracone and metastyle which are equal in size, situated parallel to a protocone and hypocone which are also similar in size. The latter cusps are lower than the paracone and metastyle. The enlarged and posteriorly elongated talon which charac-
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. A PLIOCENE URSID FROM SOUTH AFRICA 129 The M^ (L 12637) is an important specimen, since although it is incom- plete, its morphology indicates that the affinities of the Langebaanweg agrio- theriine lie with Agriotherium rather than Indarctos. It consists of a paracone and metastyle which are equal in size, situated parallel to a protocone and hypocone which are also similar in size. The latter cusps are lower than the paracone and metastyle. The enlarged and posteriorly elongated talon which charac- terizes the M^ of Indarctos is not in evidence. This tooth is appreciably smaller than the M^ and its dimensions are estimated to be 25 X 25 mm. It is thus smaller than the M^ of previously described species of Agriotherium (see Frick 1926: 81). A reconstruction of the posterior upper dentition of the Langebaanweg agriotheriine is illustrated in Figure Fig. 2. A reconstruction of the posterior upper dentition of Agriotherium qfricanum based on the specimens L 1868C, L 2045, L 1868E and L 12637 (Natural size). Little can be said of the lower incisors which are preserved (L 1868A, B, L 1844, L 3141) (Plate 20 A) other than that they are large and agree in all morphological respects with the corresponding teeth of Indarctos lagrelli (Zdan- sky 1924) and an Indarctos specimen from Samos (Helbing 1932). No descrip- tions or illustrations of the lower incisors of Agriotherium could be located, but presumably they are essentially the same as those of Indarctos. The M3 (L 12561) (Plate 20 B) is a single-rooted and low-crowned tooth with an almost circular and flat occlusal surface. The antero-buccal part of the crown is inflated and there is a wear facet in this region angled from the occlusal surface across the inflation towards the cingulum. This presumably results from occlusion with the lingual surface of the paracone or metastyle of M^. This is an indication that the post-carn
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
