GENERA OF THE ARCIFEROUS ANURA. 107 



V. Prefrontals and pterygoids wanting. 

 Parietals not embracing frontals. 

 Orbitosphenoid separated by membrane from prootic 

 Vestibule, internal wall osseous. 

 Premaxillaries embracing a fontanelle. 

 Dentigerous plates on the parasphenoid. 



Carpus and tarsus cartilaginous. 



Vertebra3 opisthocoelian. 



Occipital condyles on cylindrical pedestal. 



Mandible elevated by tendon, which arises frohi atlas and moves over o. parietale. 



Desmognathid^. — One genus, Desmognathus, North America. 



This family is now first characterized. 



The absence of o. prefrontale does not appear to be the result of its confluence at 

 any late period, with the nasale ; its ordinary position is traversed by the frontal 

 suture. The frontal bone is decurved, and closes the preorbital aspect of the super- 

 palatal vacuitj', usually open. 



D. No anterior axial bone. Palatines in contact, prolonged over parasphe- 

 noid, bearing teeth on posterior external margin. 



VI. Prefrontals and pterygoids present, well developed. 

 Frontal not embraced by parietals and prefrontals. 

 Orbitosphenoid separated by membranous wall from prootic. 

 No dentigerous plates on the parasphenoid. 



Carpus and tarsus ? 



Vertebrae ? 



Postfronto-squamosal arch or ligament none. 



Occipital condyles sessile. 



Htnobiid^. — Genus Hynobius, Japan. 



E. No anterior axial bone. Palatines with posterior separate processes ex- 

 tending over the parasphenoid, bearing teeth on their inner margins. 



VII. Prefrontals and pterygoids present. 



Parietal entirely separated from prefrontals by broad frontals. 



Orbitosphenoid confluent with prootic. 



No dentigerous plates on the parasphenoid. 



No postfronto-squamosal arch or ligament. 



Carpus and tarsus osseous. 



Vertebrae opisthocoelian. 



Occipital condyles sessile. 



Salamandrid/B.— Two genera : Salamandra, Triton, Eegio Palajarctica. 



