PLATE LIII. 

 Jurassic Dinosaurs. — Predentata. 



CAMPTOSAURIDiE. 



Page. 

 Fig. 1. Skull of Camptosaurus medius Marsh ; seen from the left side ; one-fourth 



natural size 197 



Fig. 2. The same skull, with brain cast in position ; seen from above ; one-fourth 



natural size 197 



a, exterior narial opening; an, angular; bo, basioccipital ; d, dentary ; /, 

 frontal; fp, postfrontal; if, infraorbital fossa; j, jugal; I, lachrymal; 

 m, maxillary ; it, nasal; o, orbit; pd, predentary; pf, prefrontal ; pm, pre- 

 maxillary; q, quadrate; qj, quadratojugal; s, squamosal; sn, surangular; 

 s/, supratemporal fossa; so, supraorbital bone. 



Fig. 3. Tenth upper tooth of Camptosaurus medius ; natural size 197 



Fig. 4. Fifth lower tooth of same species; natural size 197 



a, outer view; 6, posterior end view; c, inner view. 

 350 



