3 2 



ELEMENTARY ZOOLOGY. 



salamander, of which there are several species. It has 

 a series of yellow spots on a background of black or green- 

 ish-black. It belongs to the genus Amblystoma, and is 

 found in moist places beneath logs, in cellars, or even in 

 cisterns. It is six or eight inches in length. The water 

 dog or "hell-bender" is found in the Ohio river and its 

 tributaries. 



FIG. 119. Tailed amphibians. From Mivart. A, Siren; B, Amphiuma tridactyla; 

 C, Necturus. 



Questions on the Figure. Compare these three types and note 

 all the chief differences of external structure. Compare also with 

 figures you may be able to find of other Urodela. 



The newts are smaller and are found in ditches and slug- 

 gish brooks, under sticks and stones. The species vary 

 in color .from yellow and reddish to olive green and even 

 duller colors. 



The mud-puppies (Necturus) do not lose their gills in 

 the adult, and are rather common in the rivers, ponds, and 

 lakes of the northern United States. They may reach 

 a length of two feet. 



Toads and frogs lose the tail and always lose the gills. 



