CHAPTER VII 



THE FOOD OF ANIMALS— AMPHIBIA AND FISHES OF 

 CARNIVOROUS AND INSECTIVOROUS HABIT 



AMPHIBIA 



We find the members of the class Amphibia preying upon 

 insects, worms, snails, and the like, both on land and in fresh 

 water. Only a few of the more striking adaptations in the 

 group will be mentioned, and in this connection one of the most 

 interesting species is the common Grass Frog [Rana temporarid). 

 Like the Chameleon, this animal is capable of changing its hue 

 according to the nature of its surroundings for the time being, 

 the alteration in colour being, however, less rapid. The Frog 

 also possesses a sticky tongue, which can be shot out for some 

 distance for the purpose of catching insects, but the mechanism 

 is somewhat different from that present in the Chameleon. The 



tongue here is forked, not club- 

 ended, and when not in use is 

 directed backwards, its attached 

 part being fixed to the floor of the 

 mouth far forwards. When shot 

 out, an action which can be very 

 rapidly effected, its tip brushes past 

 the front part of the roof of the 

 mouth, taking up some of a sticky 

 fluid which exudes from some spe- 

 cial glands belonging to that region 

 (fig. 364). The tongue is then quickly drawn back into the 

 mouth, carrying the catch with it. 



The Common Toad (Bufo vulgaris) captures prey much in the 

 same way as the Frog (fig. 365), and it is also fond of worms, 

 tackling even large ones with the aid of its feet. 



Some of the tailless Amphibians, such as the Tree- Frogs, of 

 which a little green species {Hyla Europea) is well knoAvn on 



82 



Fig. 364. — Tongue of Frog extended to secure 

 its Prey 



