432 



MANUAL OF ZOOLOGY 



some teeth are altogether absent ; in others the webs 

 between the toes are not developed; in some tree-frogs 

 (Hyla and allied genera) the toes terminate in sucking 

 discs. A less superficial point of divergence from the 

 structure of the common American frogs is to be observed in 

 some members of the group, such as the tree-frogs and toads 

 {Hyla, Bufo, and others), in which the two halves of the 

 shoulder-girdle, instead of being firmly united in the mid- 



>.0^ 



Fig. 259. — Salamandra maculosa. (After Cuvier.) 



die line, overlap one another. In one small group the 

 tongue is absent. In some, again, there is no fish-like, gill- 

 bearing larva or tadpole — the young animal emerging from 

 the egg with the limbs formed, with no gills and no tail. 

 All the frogs and toads are grouped together to form an 

 order of Amphibia — the Anura or tailless Amphibia. 



The newts and salamanders (Fig. 259), with a number of 

 other less widely known forms, differ from the frogs and 

 toads in the possession in the adult of a well-developed tail. 

 These constitute the order Urodela or tailed Amphibians. 

 Of these tailed Amphibians, some, such as the newts and 



