300 



Mr. D. M. S. Watson on 



Back of the Skull. 



The back of the skull is quite well preserved, and, despite 

 the presence of many cracks, it is possible to make out the 

 main lines of its structure with absolute certainty. 



Fiir. 2. 



5 0c. 



PflR.Oc. 



Vantnosciunis acidirosti-is, J\rn]\\. Tv])e spcciiiien, X 1. The posterior 

 part of tlie skull I'rom above. 



IJeference-letteis as before, with: — LPar., interparietal; P.Fn., posl- 

 frontal ; P.O., postdrbital ; Par., pariehil ; I'aii.Oc, paroceipilal ; 

 S.Oc, siipraoccij-ital ; »S(i., squamosal; 8.T., suprateiiiporal ; Tab., 

 tabular. 



Parietal. 



'Ihc parietals (ixtcnd out, in tlie postorbital rej^ion, to the 

 edge of the flat dorsal surface ; in front tliey meet the 

 frontals ; just heliind the orbits tlieir outer borders have a 

 scjuare step, by which tlicy articulate with the postfrontals; 

 posteriorly their borders are turned down and covered by 

 tlie interparietal and the tabidarcs ; at the postero-lateral 

 corner they articulate by suture; with tlie snpratemporal and 

 squamosal, and the rest of the lateral border overlies the 

 postorbital. 



