164 



VERTEBRATE SKELETON 



The proolic pillar is well developed, a bar connecting it with the otic capsule. 

 In front it is connected with the supraseptals by marginal and medial parietal 

 taeniae, which have no connecting cross bar. The interorbital septum is imper- 

 forate and sphenethmoid cartilage and orbitonasal fenestras are lacking. The 

 columella auris is connected with the hyoid (ceratohyoid), and the ventral part 

 of the arch forms the small anterior cornu. 



Fig. 176. — Side and ventral views of chondrocranivun of Crocodihis with membrane 

 bones of left side of latter (Shiino, '14). ch, ceratohyoid; cp, cochlear prominence; ct, 

 trabecula communis; ec, extracolumella; fc, feo, cochlear and epioptic fenestrae; fo, fp, 

 optic and prootic fenestrje; fv, vestibular fenestra; io, interorbital septum; j, jugular 

 foramen; /, lacrimal bone; Up, posterolateral concha (anterior, just in front of it); Ip, 

 parietal lamina; m, median lateral taenia; mx, maxilla; n, naris; pbl, basitrabecular 

 process; pf, postfrontal; pi, palatine; pm, premaxilla; po, parotic crest; pp, preotic 

 pillar; ps, parasphenoid; pt, pterygoid bone; ptc, pterygoid cartilage; q, quadrate; qj, 

 quadratojugal; 55, supraseptal plate; t, trabecula; tm, marginal tsenia; tp, posterior 

 tectum; v, vomer; z, zygomatic. 



The skull of the adult Crocodilia (figs. 177, 178) is elongate, has 

 both superior and inferior fossae, and in recent species the post- 

 temporal fossa is open. The superior fossa is small, the inferior 

 larger in earlier than in recent species. All occipitaUa are distinct, 



