90 ranadjE. 



the distinctive characters of the whole group are most ob- 

 viously and unequivocally developed, — a test insisted upon, 

 I believe, by all who have even professed to believe in the 

 existence of such types of form, — it is in the family Ranada 

 that we may expect to find the typical character of the pre- 

 sent class of animals; and the truth of this test is not in- 

 validated by the absurd and even ludicrous instances of its 

 breach, of which some of the most strenuous asserters of the 

 principle have been guilty. To apply to this test only one 

 or two of the structural or j)hysiological peculiarities of the 

 class. The most remarkable and important of all is the 

 change, which has already been mentioned, from the con- 

 dition of a fish to that of a reptile; and in this respect, 

 whilst we must consider the permanent pisciform condition 

 of the Proteus, the Siren, and others, which retain their 

 branchial respiration throughout life, as an abnormal form 

 leading towards the fishes, and the Cacilia, on the other 

 hand, as probably approximating the Ophidian Reptilia ; 

 the caducibranchiate groups — and especially the present 

 family — exhibit the phenomena of this metamorphosis to 

 the greatest extent, the change which they undergo being 

 certainly more complete than that of any of the other 

 forms. The cutaneous respiration is another peculiar 

 characteristic of the class ; and there is no doubt that 

 this function also is enjoyed by the Frogs in the highest 

 degree. 



The innocent and very useful species about to be de- 

 scribed, is one of the most common of our vertebrated 

 animals. It is found in almost all parts of this island, 

 wherever there is a river or a pool, or even sufficient shade 

 to maintain the degree of moisture necessary to preserve 

 the respirable condition of the skin ; for the presence of a 

 considerable quantity of water, although requisite for the 



