SOUTH AFRICAX THliROCEt^lJ ALlAN REPTILES. 



355 



other known Tlieroceplialians, tliere are four openings. If the 

 anterior part of the palate be compared with tliat in Mosclio- 

 rhiiius, it will be seen that the difterence is that the anterior ends 

 of the p.ilatines pass inwards, and meet the prevomers dividing 

 what were large internal nares into anterior and posterior 

 portions —the posterior alone being, as Haughton has suggested, 

 the internal nares. What has happened is exactly comparable to 

 what has liappened with the external nares in Ghamoeleon, where 

 the original opening becomes divided into two by the })refrontal 

 passing forwards. 



Haugliton discusses the affinities of Wha'itsia with Tliero- 

 ceplialians, Gorgonopsians, and Cynodonts, and inclines to regard 

 it as a highly specialised Gorgonopsian, but it seenjs to me that 

 it is a true but aberrant Tlierocephalian. 



Hefeyences to lettering. 



Aug. Angular ; B.O. Hasioccipital ; B.S. liasisplienoid ; Dent. Dentary ; 

 Ec.P. Ectopterygoid or Traiispalatiiie ; JSp.P. Epipterygoid ; Fr. Frontal; Ju' 

 Jugal; 3Ix. Ma>alla; JNTa. Nasal ; OpO. Opisthotic or Paroccipital ; Fa. Parietal; 

 Fal. Palatine : Fjiuv. Premaxilla ; FrF. Prefrontal ; FoO. Postorbital ; Ft. 

 Pterygoid; F.Vo. Prevonier ; Sm.v. Septoniaxilla ; Sq. Sc^uamosal ; Vo — Fa.S. 

 Vomer =Parasphenoid. 



Pro-. Zool. Soc— 1920, No. XXTV 



24 



