Chapter II 

 URODELA— TAILED BATRACHIANS 



In the Batrachians belonging to this order the tail 

 persists throughout life ; they are provided with two pairs 

 of limbs, exceptionally with only the anterior pair. The 

 body is always more or less elongate, and those species in 

 which the limbs are well developed suggest lizards by their 

 shape, while those in which the limbs are very small and 

 rudimentary are eel-shaped ; every intermediate stage, 

 however, exists between the two extremes. 



The Tailed Batrachians are divided into the following 

 four families — 



I. The Salamandrid^, which have no gills in the per- 

 fect form. Eyelids are well developed, both jaws 

 are toothed, and four limbs are present. 

 II. The AMPHiuMiDiE, which likewise have no gills in 

 the perfect form, have the jaws toothed, and both 

 pairs of limbs are present. They have, however, no 

 eyelids. 



III. The Proteid^, in which the gills persist through- 



out life. The jaws are toothed, and both pairs of 

 limbs are present ; they have no eyelids. 



IV. The SiRENiDiE, which also retain the gills. The jaws 



are toothless and covered by a horny sheath ; the 



eyelids and the hind limbs are absent. 



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