FIRE-BEI,I,IED FROGS. 

 (Natural size.) 



AMPHIBIANS 



CHAPTER I 



GENERAL CHARACTERISTICS Class Amphibia 

 FROGS AND TOADS ORDER ECAUDATA 



IN POPULAR estimation frogs and toads together with their near relatives the 

 newts and salamanders, are regarded as Reptiles, but they are really very different, 

 and constitute a class by themselves, being in many respects intermediate between 

 Reptiles and Fishes. From the mode of life of its members the very appropriate 

 name of Amphibians has been proposed for the class, and is the one which should 

 be adopted, although the term Batrachians, which more properly applies to frogs 

 and toads alone, is not unfrequently used in the same sense. Agreeing with the 

 higher Vertebrates in the structure of their limbs, which are divided into the same 

 number of segments as in Mammals and Reptiles, and supported by corresponding 

 bones, existing Amphibians are distinguished from Reptiles by the absence of any 

 ossification in the basioccipital region of the lower surface of the hinder part of the 

 skull, inconsequence of which the latter is articulated to the first vertebra by means 

 of two condyles formed exclusively by the occipital bones. A further important 

 point of distinction is afforded by the absence in the embryo of those membranous 

 structures known as the amnion and allantois. Moreover, the great majority of 

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