CHAPTER 27 



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Class Amphibia. 



Frogs, Toads, 



Salamanders, 



and Others 



HE common amphibians are the frogs, 

 toads, and salamanders (Fig. 267). They 

 spend part or all of their existence in the 

 water or in damp places. Most lay their 

 eggs in the water; and the larvae, which 

 breathe with gills, are known as tadpoles or 

 pollywogs. Some amphibians are often con- 

 fused with reptiles, especially the lizards, 

 because of their similarity of form, but al- 

 most all reptiles possess scales and are not 

 slimy, whereas amphibians usually have a 

 smooth slimy skin without scales except in 

 a few rare species. 



Introduction 



There are 10 orders of extinct Amphibia, 

 and three orders of living forms, which are 

 as follows: 



1. The Apoda (Gymnophiona), which are 

 commonly called caecilians, are wormlike 

 amphibians inhabiting tropical and sub- 

 tropical regions. 



2. The Caudata are amphibians with tails; 

 they include the mud puppies, sirens, and 

 salamanders. 



3. The Salientia are frogs and toads, which are 

 tailless in the adult stage. 



The United States is a paradise for the 

 student of Amphibia because it contains 

 large numbers of species and individuals. 

 Since all amphibians require moisture, they 

 should be looked for in or near bodies of 

 fresh water and in moist places such as 

 under logs and stones in damp woods. 

 Among the most interesting features of am- 

 phibians are their ability to change color, 

 their powers of regeneration, their varied and 

 often curious breeding habits, their methods 

 of spending the winter, and their poisonous 

 secretions. As is the case with birds, more 

 amphibians are heard than seen; hence it is 

 advisable to become acquainted with the call 

 notes of the various species. Many of these 

 can be easily learned from the field record- 

 ings made and narrated by Charles M. 

 Bogert in 1958. 



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