190 



ANIMAL STUDIES 



pearing as a smooth circular area behind the eye. Organs 

 of touch, smell, and taste are likewise developed in varying 

 degree of perfection. 



180. Breeding-habits. While the great majority of am- 

 phibians mate in the spring and deposit their eggs in the 

 water, often to the accompaniments of croakings and pip- 

 ings almost deafening in intensity, several species, for 

 various reasons, have adopted different methods. Some of 

 the salamanders bring forth young alive, and several species 

 of toads and frogs are known in which the young are cared 

 for by the parent until their metamorphosis is complete. 

 In one of the European toads (Alytes) the male winds 

 the strings of eggs about his body until the tadpoles are 



FIG. 111. Salamanders. The 

 axolotl (the larva of Am- 

 blystoma tigrinum) and 

 the newt (Diemyctylus to- 

 rosus). 



ready to hatch ; and in a few species of tree-toads the eggs 

 are stored in a great pouch on the back of the parent until 

 the early stages of growth are over. In the Surinam toad 

 of South America the eggs are placed by the male on the 

 back of the female, and each sinks into a cavity in the 

 spongy skin. Here they pass through the tadpole stage 

 without the usual attendant dangers, and emerge with the 

 form of the adult. 



