I THE AMPHIBIA IX GENERAL 3 



THE APODA 



The Apoda, or Ccecilians, are creatures of wormlike form, 

 entirely devoid of limbs and limb girdles. The skin is 

 smooth and thrown into transverse rings. In some forms 

 small scales are found embedded in the integument. The 

 eyes are small or absent. The Apoda are generally found 

 in moist ground, in which they burrow, and they are confined 

 to tropical or subtropical regions. No species occur in North 

 America north of Mexico. 



THE URODELA, OR TAILED AMPHIBIANS 



The tailed amphibians occupy a more primitive position 

 than the tailless forms. A large proportion of them live in 

 the water, and the lower members of the group retain their 

 gills in the adult state. The Urodela are divided by Gadow 

 into four families as follows : — 



Jaws without teeth. No hind limbs . . . Sirenidce. 

 Both jaws with teeth. Fore and hind limbs 

 present. 

 Gills persistent. No eyelids or maxillary bones Proteidcz. 

 Gills usually absent in the adult. Maxillary 

 bones present. 



Eyes with lids SalamandricUe. 



Eyes devoid of lids Amphiumidce. 



The Proteidse constitute the most primitive of the Uro- 

 deles. At the sides of the neck there are three pairs of 

 external gills. The species are aquatic in habit. There are 

 only three genera, two of which, Necturus and Typhlomolge, 

 are confined to North America. The remaining genus, Pro- 

 teus, represented by a single species, P. angninus, is found 

 only in the caves of Austria. This species occurs in deep 

 cool water in regions of complete darkness. Its eyes, like 



