166 Annals of the South African Museum. 



The piiieal foramen is far back on the broad parietal bar, its posterior 

 end being only 2 mm. in advance of the occipital plate. From either 

 side of the foramen a groove passes forward to the orbital border, the 

 preparietal region and the lateral portions of the parietal bar standing 

 out as prominences. 



The parietal is a short, broad bone, an outer narrow prolongation 

 passing between the postorbital, interparietal and tabulare. It forms 

 no part of the border of the fossa. At the back of the parietal bar 

 the bone is bent abruptly and lies vertically in front of the inter- 

 parietal. 



The occipital plate is broad and shallow and almost vertical. Its 

 upper portion is formed by the broad interparietal, which has a 



' EO "Par.Occ. 

 B.o. 



FIG. 42. Myosaunts <jracilis, Htn. Sketch of occipital plate. Natural size. 



vertical median keel. Below the interparietal lies the supraoccipital, 

 whose upper border is semicircular, and which forms the border of the 

 upper half of the foramen magnum. Below it meets the exoccipital 

 and the paroccipital, but takes no part in the border of the post- 

 temporal fossa. 



Lateral to the interparietal and the supraoccipital lies the tabulare, 

 a Ion"-, narrow bone which extends down almost to the lateral vacuity, 

 but which takes no part in forming the border of the vacuity. 



The condyle is tripartite. The exoccipitals form the lateral portions, 

 while the basioccipital forms the lower median third. This latter lies 

 in advance of the exoccipital portions, so that the plane of the back of 

 the condvle is inclined and not vertical. The exoccipital forms the 

 half of the lower border of foramen magnum. It articulates laterally 

 with the paroccipital, the two being separated by a well-defined 



suture. 



The paroccipital is short and stout. It forms more than half the 

 border of the lateral vacuity and also encloses most of the foramen 

 jugulare. Below this foramen it articulates with the basioccipital. 



