272 



CAPT. D. M. S. WATSON ON SEYMOURIA, 



lappet passing vertically downward, the inner border of this 

 forms part of the margin of the foramen magnum, the outer, that 

 of the post-temporal fossa. 



The tabular has a similar occipital flange forming the outer 

 margin of the post-temporal fossa and covering a large area of 

 the posterior surface of the paroccipital. 



My skull suggests the presence of some sort of a flange on the 

 ventral surface of the tabular articulating with the end of the 

 paroccipital process. 



Text-figure 4. 



Seymouria bayloriensis Broili.— Palate, X |. Drawn from Munich A. 



Reference letters as before with :— B.Pt., the basipterygoid articulations on the 

 basisphenoid ; R.Pal.Th., right palatine tusk. 



Pterygoid. — The pterygoid is completely exposed in Munich A. 



The quadrate ramus forms a vertically standing plate whose 

 posterior surface is concave. The outer margin has a long 

 suture with the squamosal below the otic notch, ventrally it 

 separates from that bone so as to leave exposed an area of the 

 ^quadrate, with which bone it has a large powerful suture. 



The inner margin of the quadrate ramus approaches the 

 anterior border of the prootic closely, the bone in this region 

 though deep not nearly reaching the skull-roof. This part of the 

 ramus bears towards its ventral edge a large, well-developed, 

 slightly cupped articular facet. 



When the perfectly preserved pterygoids and basisphenoids of 

 Munich A and B are compared, it is seen that there is a large 



