. Catalogue of the fossil Mammalia in the British museum, (Natural History). Mammals, Fossil. 204 MAESUPIALIA. Family MACROPODID^. Dentition:—1.\, C. ^\ Pm. ?, M. |. The upper incisors are secant, and arranged in a continuous arched series, distinctly sepa- rated in the median line ; the first being often larger than either of the others; the lower incisor is secant and proclivous, and the teeth of opposite sides frequently bite against one another. The upper canine, when present, is often deciduous, and generally small. The diastema is long. The premolars are either secant or triangular, and
. Catalogue of the fossil Mammalia in the British museum, (Natural History). Mammals, Fossil. 204 MAESUPIALIA. Family MACROPODID^. Dentition:—1.\, C. ^\ Pm. ?, M. |. The upper incisors are secant, and arranged in a continuous arched series, distinctly sepa- rated in the median line ; the first being often larger than either of the others; the lower incisor is secant and proclivous, and the teeth of opposite sides frequently bite against one another. The upper canine, when present, is often deciduous, and generally small. The diastema is long. The premolars are either secant or triangular, and in the former case are generally more or less distinctly marked by nearly vertical grooves and ridges; pm. 3 is always, and pm. 4 occasionally deciduous, the latter tooth being preceded by a milk- molar. The true molars are either quadritubercular or transversely ridged; and m. 1 is occasionally deciduous. The mandible has a deep pit and perforation in the masseteric fossa, and its condyle is flat, transversely shortened, and not separated by a deep notch from the coronoid process. The fore limbs are always shorter than the hind ones, although their relative proportion varies much in the different forms; the scapula and humerus are frequently broad, and Fiff. Bettmgia grayi (Gould). Lateral view of skull; from AuatraHa. \. (From the ' Quart. Journ. Geol. Soc.') the latter nearly always has an entepicondylar foramen. The olecra- non is well developed; the calcaneum and astragalus are of a peculiar type, the former being characterized by the truncation of its distal articular surface. The manus has five subequal digits; but the hind foot has the second and third digits much smaller than the others, and enclosed in a common integument, the hallux being absent in all recent forms except Hypsiprijmnodon, and the fourth digit always larger than either of the others. The femur is charac- terized by a projection for muscular attachments at the outer side of the external distal c
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Keywords: ., bookauthorlydekker, bookcentury1800, bookdecade1880, bookyear1885
