560 AMPHIBIALA. 



the popular belief of their having descended from the clouds in 

 showers. 



As soon as the frog has thus assumed its perfect form, it feeds no 

 longer on vegetables, but on auiinal food : supporting itself on 

 small snails, worms, &c. and insects. For the readier obtaining its 

 prey, the structure of its tougue is extremely well calculated, being 

 so situated that the root is attached to the tore rather than the hind 

 part of the mouth 5 and when at rest, lies backwards, as if the ani- 

 mal was swallowing the tip. By this means the creature is enabled 

 to throw it out to some distance from the mouth, which is done 

 with great celerity, and the bifid and glutinous extremity secures 

 the prey, which is swallowed with an instantaneous motion, so quick 

 that the eye can scarcely follow it. 



The frog can hardly be said to arrive at its full size till the age of 

 about rive years, and is supposed to live at least twelve or fifteen 

 years. 



The frog is extremely tenacious of life, and, like other amphibia, 

 will survive for a considerable space the loss of many of its organs* 

 If confined entirely under water, it is still enabled to support its ex- 

 istence for several days, as appears by Sir Thomas Brown's experi- 

 ment, who kept a frog under water six days. On the contrary, it 

 cannot so well dispense with the want of water, and is unable to 

 survive too long an exposure to a dry air and a hot sun. It is> 

 therefore, particularly careful to secure a retreat where it may en- 

 joy the benefit of shade and a sufficient supply of moisture. It 

 delights, however, to bask occasionally in a moderate sunshine, and 

 is unable to support severe cold. 



Tree-Fiog, 

 Rana arborea. Linn. 



In the beauty of its colours, as well as in the elegance of its 

 form, and the agility of its movements, the tree-frog exceeds every 

 other Europeau species. It is a native of France, Germany, Italy, 

 and many other European regions, but is not found in the British 

 islands. Its principal residence, during the summer months, is on 

 the upper parts of trees, where it wanders among the foliage in 

 quest of insects, which it catches with extreme celerity, stealing 



