THE MOST PRIMITIVE KNOWN REPTILE. 



269 



opens out from the basisplienoid. A broken face about 5 mm. in 

 advance of the tubera shows that in that region the basisplienoid 

 is a thin plate scarcely a millimetre thick medially. 



Text- figure 1. 



prix. 



Seymouria bayloriensis Broili. — Restoration of the palate, X f. 



General shape and palate from the types in Munich. Details of maxillary dentition 

 from fragments in my possession. Basisplienoid and occipital region from 

 my skeleton. 



Reference letters: — B.Oc, hasioccipital ; B.Sp., basisplienoid; Ect.Pt., ectoptery- 

 goid ; Ex.Oc.,exoccipital ; Mx., maxilla: P.Mx., premaxilla ; Pal., palatine ; 

 Par.Oc, paroccipital ; Pn.O., prootic ; Pr.V., prevomer; Qu., quadrate; 

 X, autogenous basipterygoid process ? 



Parasphenoicl. — The parasphenoid is well shown in Munich B 

 as a short narrow rostrum projecting forward in the palate 

 between the pterygoids. 



The type of Conodectes shows that it supports a large ethmoidal 

 ossification which surrounds the anterior part of the brain. 



Eoooccipital. — The right exoccipital is well shown in my skull, 



