1 



134 



AMPHIBIA 



CLASS II 



Mastodonsaurus, Jaeger (Figs. 204, 206, 226). Largest of all Labyrintho- 

 donts, skull 1*25 m. long, depressed, and with large orbits behind the 

 middle. External bones sculptured, sensory canals prominent. Premaxillae 

 pierced for the passage of the two greatly enlarged teeth at Symphysis of 

 lower jaw. Vomers with a pair of tusks in front of the posterior nares, and 

 another near the hinder margin ; palatines with a 

 Single series of large teeth. Dentine excessively 

 complicated. Interclavicle rhomboidal, clavicles 

 triangulär, all strongly sculptured. Ischium very 

 large, pubis small, ilium elongated, and articulating 

 with the sacral ribs. Limbs very imperfectly 

 known, and dermal armour not ^_ 



observed. The most perfect re- 

 mains are from the Lettenkohle of 



Fig. 226. 



Skull of Mastodonsmcrus giganteus, Jaeger. A, 

 Orbit ; N, External nares ; X, Opeiiings for the 

 passage of tlie tusks of lower jaw ; Pmx, Pre- 

 niaxilla ; Mx, Maxilla ; Na, Nasal ; La, Lachrymal ; 

 P/r, Prefrontal; Fr, Frontal; Ptf, Postfrontal; 

 Pa, Parietal ; PtO, Postorbital ; Sq, Squamosal ; 

 SO, Supratemporal ; Ep, Epiotic ; J, Jugal ; Qj, 

 Quadrato-jugal ; ExO, Exoccipital (after E. Fraas). 



Fig. 227. 



Lower jaw of Capito' 

 saur^is nasut^l,s, v' 

 Meyer. Trias); Bern- 

 burg. 



Footprints of Cheirotheriinn 

 barthi, Kaup. Buntsandstein ; 

 Hessberg, near Hild berghausen. 

 i/e (after Owen). 



Gaildorf and Oedendorf in Würtemberg. Fragments occur also in the Upper 

 Trias of England and India, and possibly also in the Buntsandstein of Alsace 

 and the Black Forest. 



Lahyrinthodon, Owen. Upper Trias ; England. Bhytidosteus, Owen. 

 Karoo Formation ; Orange Free State. Pachygonia, Gonioglyptus, Huxley. 

 Trias ; East India. 



Footprints. — Stegocephalian footmarks are not uncommon in the Goal 



