XII 



TERRESTRIAL VERTEBRATES: AMPHIBIA 



1 . Classification 



Class Amphibia 



*Subclass i. *Stegocephalia. Devonian-Trias 

 Order i. *Labyrinthodontia. Devonian-Trias 

 Suborder i. *Ichthyostegalia. Upper Devonian 



*Ichthyostega; *Elpistostege 

 Suborder 2. *Embolomeri. Carboniferous 



*Eogyrimis; *Loxomma 

 Suborder 3. *Rhachitomi. Carboniferous-Triassic 



*Eryops, Lower Permian ; *Cacops, Lower Permian 

 Suborder 4. # Stereospondyli. Triassic 



*Capitosaurus, Upper Triassic; *Buettneria, Upper Triassic 

 Order 2. *Phyllospondyli. Carboniferous-Lower Permian 



*Bra?ichiosaurus, Lower Permian 

 Order 3. *Lepospondyli. Carboniferous-Permian 



*Dohchosoma, Carboniferous ; *DipIocaulus, Permian ; *Micro- 

 brachis, Permian 

 Order 4. *Adelospondyli. Carboniferous-Lower Permian 

 *Lysorophns, Carboniferous 

 Subclass 2. Urodcla (= Caudata). Jurassic-Recent 



Molge; Salamandra; Ambystoma; Necturus 

 Subclass 3. Anura (= Salientia). Carboniferous-Recent 

 *Miobatrachus; *Protobatrachiis ; 

 Rana; Bufo; Hyla; Pipa 

 Subclass 4. Apoda (= Gymnophiona = Caecilia). Recent 

 Ichthyophis; Typhlonectes 



2. Amphibia 



During the later part of the Devonian period a population of lung- 

 fishes lived in the pools and there is every reason to suppose that some 

 of these animals, first crawling from pool to pool and then spending 

 more time on the land, gave rise to the terrestrial populations that 

 we distinguish as amphibia. No doubt the early efforts at land life 

 were crude. The whole locomotory and skeletal system comes under 

 a completely new set of forces when the support of the water is with- 



