I.] THE COMMON FROG. 3 



If it is a fact that all the various species of animals 

 have arisen through ordinary generation one fron. 

 another by a process of development, the life history 

 of the Frog may with reason be expected to have _|^ • 

 some bearing upon such a process, since every Frog 

 begins its free existence with the organization of a 

 Fish, and after undergoing a remarkable " Metamor- -t • 

 phosis," attains the condition of an air-breathing 

 quadruped, capable of easy and rapid terrestrial 

 locomotion. 



There is a matter with respect to which the zoolo- 

 gist can hardly avoid regarding the botanist with 

 envy. The creatures sought after by the latter may 

 be rare or inhabitants of stations difficult of access, 

 but at any rate they are incapable of flight or con- 

 cealment, and specimens of some kind or other 

 generally present themselves in plenty. ' 



On the other hand not only does the townsm.an of 

 a thickly-peopled land like our own, often meet wnth 

 fewer animals in his country walks than he antici- 

 pated, but the explorer of tropical lands and virgin 

 forests has frequently to endure disappointment from 

 the contrast between the richness of a known local 

 fauna and the little to be actually seen of the animal 

 population of the place. 



Frogs and Toads, however, are often enough seen 

 both at home and abroad, and when perceived 

 generally fall a far more ready prey to the collector 

 than do the swift-running Lizards and small Beasts 

 which are the commonest ground-animals met with 

 besides. The group is also rich in species as well as 

 in individuals, and it is spread over the far greater 4-- " 



B 2 



