2674 NEWTS, SALAMANDERS, AND CCECILIANS 



lungs pass over the gills, with the apparent object of more fully oxygenating the 

 blood in the latter. 



The eel-like or three-toed salamander {Amphiuma means] represents 



another North-American genus, ranging from the Mississippi to South 

 Salamander . . 



Carolina, and distinguished by its extremely elongated and eel-like 



form, and the small size of its limbs, each of which terminates in three or two- 

 minute toes. The tongue is indistinctly defined, covering the whole of the floor of 

 the mouth, to which it is everywhere adherent; there is a gill aperture on each side 

 of the neck, and four internal gill arches are present. The head is relatively small, 

 with a rather long and narrowing muzzle, at the extremity of which are the small 

 and widely -separated nostrils; the eyes are likewise minute; the lips are un- 

 usually thick and fleshy, and the short compressed tail is keeled superiorly. 

 The smooth and slimy skin is of a uniform blackish-brown color, although 

 rather lighter below than above. In total length, full-grown examples measure 

 about thirty-one inches. From the difference in the number of the toes it 

 has been thought that there are two species, but^ince the two-toed and three- 

 toed forms are in other respects similar, it seems preferable to regard them as 

 varieties or local races of a single species. These salamanders are inhabitants of 

 muddy waters, frequently burying themselves in the mud at the bottom, in one in- 

 stance to the depth of a yard or more, in thick clayey mud of the consistence of 

 putty, in which they burrowed like worms. They also frequent the irrigation 

 channels in rice fields, while they occasionally venture on land. Their food com- 

 prises fresh-water mussels, fish, beetles, other insects, and crustaceans. Beyond 

 the fact that the female lays eggs, in which the tadpole lies coiled up until it attains 

 several times the length of its chamber, little is known as to the breeding habits of 

 this species. 



THE GILLED SALAMANDERS 

 



Family PROTEID^ft 



Represented only by the curious olm of the subterranean waters of Carniola 

 and other parts of Europe, and by an allied genus in North America, the gilled sal- 

 amanders take their title from the permanent retention of external gills, on which 

 account they may be regarded as some of the lowest representatives of the order. 

 In addition to this primary feature, they are characterized by the absence of the 

 upper jawbone or maxilla, although the premaxilla is present, and, like the lower 

 jaw, furnished with teeth. There are no eyelids, and the bodies of the vertebrae 

 are cupped at both extremities. There are differences in the external form of the 

 two representatives; the olm being a long, snake-like creature with small limbs, 

 whereas the American species resembles a salamander. 



O1 Known for more than a couple of centuries, the remakable creature 



to which Oken gave the name of olm is the sole representative of its 



genus, and is technically known as Proteus anguineus. From its American ally it 



