CLASSIFICATION OF AMPHIBIA 231 



The water-dog or mud-puppy (Fig. 188) ( Nectu'rus macula'lus) is a rather 

 common, clumsy form found in the Mississippi Valley and the region of the 

 Great Lakes and east to the Alleghenies. They are nocturnal, but vora- 

 cious, feeding on insects, worms, small fish, and crustaceans. Those in 

 our laboratory were 15 inches long with dark brown spots. 



The blind Pro'teus angui'nus of Europe (Fig. 189) belongs to this family. 

 It is white and lives in total darkness in a temperature of about 50 F. If 

 brought to the light the skin will ultimately change to a dark color. 

 There is a similar species (Typhlomol'ge rath'buni) in Texas. 



Family Amphi'umidae. These animals are without gills in the adult 

 stage. They have teeth in both jaws. They have four small, weak 

 limbs. 



The hellbender (Cryptobran'chus alleghanien'sis) is a stout-bodied, four- 

 footed, ugly, but harmless amphibian, which is sometimes 2 feet in length. 

 It is brown or gray above and lighter below. It feeds on worms, crayfish, 

 fish, and such other creatures as it can obtain in its aquatic habitat. It is 

 restricted in its distribution to the streams of the mountainous regions of 

 the eastern United States. 



Fig. 190. Congo snake (Amphiu'ma me'ans). (From Holder's " Elements 

 of Zoology," American Book Co., Publishers.) 



The giant salamander of Japan (C. japon'icus) reaches a length of 4 to 

 5 feet. It lives in small streams and mountain meadows of Japan and 

 China, from 600 to 4500 feet above sea-level. Sasaki reports that it lives 

 singly, lying concealed under rocks, in swift, thickly shaded, small, clear, 

 cold streams. It feeds on animals which it can capture in the water and 

 may be caught with a fish-hook. It is used for food by the Japanese. 



The "Congo snake" (Amphiu'ma me'ans) (Fig. 190) is eel-like, with 

 four weak limbs, having two or three toes each. Its general color is black, 

 with lighter under parts. It attains a length of .3 feet. It lives in the 

 swamps and rice fields of the southeastern United States. It feeds on 

 crayfish, mollusks, and fishes. It is quite harmless. 



Family Salaman'dridce, or salamanders and newts, are our most common 

 Urodela. All are harmless, and are generally but erroneously called 

 lizards. They have no persistent gills. They have two pairs of weak 

 limbs. Nearly all have movable eyelids and teeth in both jaws. There 

 are twelve or fifteen species in the United States. 



