80 



Annals of the South African Museum. 



slightly forwards. The articular of the lower jaw is closely applied 

 to it. 



The occipital plate is weathered and broken. There is a large 

 foramen magnum placed high up. The squamosal only forms the 

 edge of the plate and the outer boundary of the lateral post-temporal 

 fossa. Most of the side of the occipital plate seems to be formed by 

 the tabulare. Below the basioccipital condyle there is a vertical 

 mass of bone as in the other Dinocephalians. 



The lower jaw is deep and displayed only in outer view. Its total 

 length is about 215 mm. The dentary covers almost the whole of 

 the anterior half of the jaw, the lower border being formed by the 



FIG. 8. Anterior view of vertebra of Hoschosaurus longiceps. x 



splenial ; and the dentary extends backwards along the upper border 

 of the jaw for about four-fifths of its length. This posterior process 

 is much more slender than that seen in Dimetrodon. The dentary 

 carries 5 or 6 teeth, forwardly directed and presumably diminishing 

 in size posteriorly. 



The splenial forms a small portion of the symphysis and is only 

 visible along the lower border of the anterior half of the jaw. 



The back of the angular is missing ; but the notch in its lower 

 border must have been a small one. The bone overlaps the articular 

 which, from below, is seen to be swollen vertically and to pass 

 forwards and upwards. 



Six consecutive vertebrae are preserved, without doubt anterior 

 dorsals. The centra are short with circular biconcave ends. The 

 lower border is concave with a slight median ridge. The sides are 



