132 



AMPHIBIA 



CLASS II 



A nth racosaiirus, Huxley. 



Fig. 221. 



Cross-section of tcotli of Loxomma allmani, 

 Huxley, near the base. Enlarged. Coal 

 Measures ; NorMiuniberland (after Embleton 

 and Abbfy). 



Skull broadly triangular, 36 cm. long, externally 

 pitted. Orbits very small, situated in hinder 

 third of the skull. Teeth externally furrowed, 

 of nearly uniform size. Vomer toothless, 

 palatines with a large tooth, and several of 

 smaller size. Dermal scales externally con- 

 vex, sharpened at the ends. Coal Measures ; 

 Northumberland. A. russelli, Huxley. 



Loxomma, Huxley (Figs. 199, 221). Like 

 the preceding, but orbits very large, irregu- 

 larly oval, and teeth of unequal size. Coal 

 Measures ; Northumberland and Bohemia. 



Eoscmrus, Marsh. Known only by a few 

 detached amphicoelous vertebrae. Coal 

 Measures ; Nova Scotia. 



Macromerion, Fritsch. Imperfectly known. 

 Permian ; Bohemia. 



Family 2. Labyrinthodontidae. {Eughjpta, Miall.) 



Ventral armouring and sclerotic ring absent. Pectoral plates large,, coarsely 

 sculptured. Infoldings of the dentine completely labyrinthodont. A few excessively 

 develojjed teeth present on the palatines, and sometimes on the vomer and symphysis of 

 lower jaw. Trias. 



Tremafosaurus, Braun (Fig. 222). Skull elongated triangular, about 25 

 cm. long, with orbits near the middle. Teeth present on jaw-bones, palatines, 

 and vomer, and inner border of posterior nares 

 fringed with small denticles. A pair of greatly 

 enlarged teeth present on symphysis of lower 

 jaw, and behind these a supplementary row of 

 small teeth. Two large vomerine tusks in advance 

 of the posterior nares, and three or four palatine 

 ones behind the same. Interclavicle rhomboid, 

 with posterior pedicle. Abundant in the Bunt- 

 sandstein of Bernburg. T. brauni, Burm. 



Metopias, v. Meyer (Metoposanrus, Lydekker), 

 (Fig. 223). Skull large, broadly triangular, with 

 elliptical orbits in anterior half, and large naria] 

 openings Nasals shorter than frontals and 

 parietals. Pectoral plates very large. Ribs very 

 powerful, distally expanded. Dentition weak, 

 teeth strongly fluted externally, especially at the 

 base, with but slight internal foldings. Teeth 

 apparently arranged like those of Capitosaurus. 

 Keuper ; ^Yiirtemberg. 



Capitosaurus, Miinst. (Figs. 224, 227). Skull with muzzle often broad 

 and obtusely rounded. Orbits small, behind the middle of skull. Nasals 

 of equal size Avith the frontals or larger. A small auditory notch adjacent 

 to the so-called epiotic. One or two powerful tusks present on vomer in 

 front of the internal nares and on palatines behind the same. Between the 



Fig. 222. 



Skull of Trematosaunis brauni, Bur- 

 nieist. Buntsandstein ; Bernburg. 

 1/4 (after Burmeister). 



