. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 12 Annals of the South African Museum. internasal bar carried a forwardly directed boss (Pareiasuchus nasi- cornis). The palatal processes of the premaxilla lie on a higher plane than the prevomers, and abut on to the girder formed by the anterior ramus of the pterygoid. Septomaxilla (fig. 1).—The septomaxilla has been found preserved in only one skull (Anthodon). Here it lies wholly within the nostril and cannot be seen in dorsal view. It shows no indication of any sculpturing as is general in the s
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. 12 Annals of the South African Museum. internasal bar carried a forwardly directed boss (Pareiasuchus nasi- cornis). The palatal processes of the premaxilla lie on a higher plane than the prevomers, and abut on to the girder formed by the anterior ramus of the pterygoid. Septomaxilla (fig. 1).—The septomaxilla has been found preserved in only one skull (Anthodon). Here it lies wholly within the nostril and cannot be seen in dorsal view. It shows no indication of any sculpturing as is general in the superficial dermal bones of the skull. Its shape is shown in the accompanying figure. From the available evidence it appears that this bone does not divide the nostril into two compartments. Squamosal. — There are only two temporal bones. Watson has argued in full that these two bones can only be the squamosal and ^ , „ .„ . quadratojugal; Sushkin has claimed to have Fig. 1.—Septomaxilla in ^ J & ' external view. Antho- found another temporal bone in the Russian SA Mmm 4020* L Pareiasaurs. Hartmann - Weinberg, who has subsequently studied this material, could not locate this " ; In none of the skulls I have examined is there anything that can be considered to form a third bone. I have examined the temporal region internally as well as externally and have also sections through it, and can definitely state that there is no "supra-temporal" bone present. The squamosal is a fair-sized bone with a not-well-defined central boss, but with clearly visible radiating bone-fibres and a few rugae. The squamosal-tabular suture runs just below the tabular ridge and reaches the posterior surface just below the posterior shelf of the tabular. Here there is a slight notch—a remnant of the large Stego- cephalian otic notch. The posterior border of the squamosal is very much thickened and in the majority of forms carries a number of bosses, wherea
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
