1034 MR. D. M. S. WATSON ON 
projection which, oceurring in Diademodon and also in Ornitho- 
rhynchus, has a long suture with the parietal. 
Quadrate region of Gorgonopsids. 
A large Gorgonopsid skull, at a slightly more advanced stage of 
evolution than Arctops, from the Hndothiodon zone of Beaufort 
West, which was collected by the Rev. J. H. Whaits and is now 
in the British Museum, shows the quadrate and the bones 
surrounding it in a most perfect manner. 
Text-figure 6. 
The quadrate and surrounding bones of a Gorgonopsid from the 
Mndothiodon zone of Beaufort West. X 1. 
A, from in front; B, from behind. 
Par.Oc., Paroccipital process; Pt., Pterygoid; Quw., Quadrate; Qu.J., Quadrato- 
jugal ; Sqg., Squamosal; Tab., Tabulare. 
The squamosal has a powerful articulation with the end of the 
paroccipital process ; the bone there sends a process dorsally and 
medially which articulates with the tabulare, postorbital, and 
