Batrachians and Reptiles of Ontario 



Class BATRACHIA. (The Batrachians.) 



Animals of this class are cold-blooded vertebrates, intermediate be- 

 tween the fishes and the* reptiles. They differ from the fishes in the 

 absence of rayed fins, the limbs being usually developed and functional 

 with the skeletal elements of the limbs of reptiles. 



The Batrachians undergo a more or less complete metamorphosis ; 

 the young (commonly known as "tadpoles") being fishlike and more or 

 less aquatic, breathing by means of external gills. These differ from the 

 gills of fishes in standing on fleshy processes of the branchial bones and 

 not on the bones themselves. 



In the tadpole, the tail is provided with a more or less distinct finlike 

 membrane, which usually disappears with age. Later in life, lungs are 

 developed, and in most cases the gills disappear. Skin mostly naked and 

 moist ; used to some extent as an organ of respiration. 



In our species reproduction is by means of eggs, which are of com- 

 paratively small size and without hard shell. These are deposited in 

 water or in damp places. 



No representative of this class found in Canada is venomous, or 

 indeed capable of inflicting injury upon human beings ; while many 

 species are of economic importance, the Toads and Tree Frogs (Hylas) 

 being particularly valuable as destroyers of noxious insects. 



Order PROTEIDA. 



FAMILY PROTEIDA. (THE MUD PUPPIES.) 



Salamanders provided with bushy external gills and having the 

 branchial clefts remaining open through life. Teeth well developed. 



GENUS NECTURUS. 

 (i) Necturus maculosus. 



(Mud Puppy.) 



This species is provided with large bushy bright red gills, forming 

 three tufts on each side. These gills are retained through life. It is 



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