186 MAEINE EEPTILES OF THE OXFOED CLAY. 



R. 2053 (Leeds Coll. 36). A small crashed skull wanting the anterior portion of the snout. 

 The dimensions (in centimetres) of. this specimen are : — 



Length in middle hue to tip of nazals 31'5 



„ of nasals 18-0 



Distance between nasals and premaxilla: 4 - 5 



Least width between orbits GV 



Width bstween outer angles of prefrontals 10-7 



„ „ „ frontal 9-0 



R. 2041 (Leeds Doll. 16). A nearly complete skull, the premaxillary region of which is well 

 preserved. The whole is, as usual, much flattened from above downwards, the palate 

 being almost entirely destroyed. 



The dimensions (in centimetres) of this specimen are : — 



Length in mid-dorsal line 52-2 



„ to tip of nasals (approx.) 34 - 5 



,, from occipital condyle to tip of snout 55-2 



,, of nasals (approx.) 195 



Distance between nasals and premaxilla: 5-5 



Least width between the orbits 6'7 



Width between outer angles of prefrontals 11-4 



„ „ ,, frontal lOT 



,, ,, „ quadrates 15 - 6 



"Width of premaxillary region 3-3 



R. 2055 (Leeds Coll. 38). Imperfect skull. 



The approximate dimensions (in centimetres) of this specimen are : — 



Skull : approximate length in mid-dorsal line 48-0 



length to anterior end of nasals 3L0 



„ of nasals 17 - 



distance between nasals and preraaxilliB 7'0 



least width between orbits 6-4 



width between outer angles of prefrontals .... 11-4 



,, ., ,, frontal 10-7 



,, ,, ,, quadrates 13'5 



R. 1529. Skull and mandible of a young individual. This specimen shows that the sculpture of 



the frontals is already well developed in the young. The teeth seem to be less rugose 

 on the outer side than in larger specimens. 



The dimensions (in centimetres) of this specimen are : — 



Skull : length in middle line from occiput to tip of nasals . . 27-5 



width between orbits 5-0 



width at outer angles of prefrontals 9'2 



length of frontal anterior to temporal fossce .... 70 



Mandible : length of symphysis (approx.) 17 - 5 



