SALAMANDERS. 26S 



ORDER II. URODELA. 



{Sala7nanders.) 



In this Order the body is lengthened, slender, 

 and lizard-like, with four well-formed limbs, 

 furnished with toes, and a long tail, which re- 

 mains through life. The ribs are very short, 

 the vertebrcd or joints of the spine numerous 

 and moveable. The tympanum, or membrane 

 of the ear, is concealed beneath the skin. Re- 

 spiration in the earlier stages of existence is 

 aquatic, the necessary oxygen being separated 

 from the water by external gills, as in the 

 tadpoles of the Anoura ; in the adult or perfect 

 condition it is aerial, and performed by means 

 of cellular lungs. Both jaws are furnished 

 with minute teeth, and there are two longitu- 

 dinal rows of equal teeth on the palate, attach- 

 ed to the bone. The head is much flattened. 



The Urodela undergo a metamorphosis similar 

 to that of the Anoura ; the young animal is a 

 tadpole of similar form, inhabiting the water ; 

 and this is the case no less with those species 

 that are terrestrial in their perfect state, than 

 with those that are permanently aquatic. In 

 the metamorphosis, the fore limbs are first 

 developed, an order contrary to that w^hich 

 prevails in the Frogs. 



The power of reproducing certain parts of 

 the body which have been injured or removed 



