Distribution 



They feel discomfort from hunger, cold, and lack of water; 

 physical comfort from food, warmth, and moisture. They feel 

 physical joy and express it in song. They certainly possess the 

 one emotion, fear. Frogs are more excited^byjfear than^are toads. 

 A frog when frightened will dash into anything or from any height. 

 A toad will proceed to the edge of a table or window, and stop 

 to examine the surroundings before jumping. 



Frogs and toads can be tamed somewhat. They will come 

 out of their burrows for food at a given time and will take it from 

 the fingers. They will get used to the movements of people and 

 to all kinds of sounds. On the other hand, they walk over one 

 another, and in fact pay no attention to one another outside of 

 the time of the breeding season. Occasionally there is an excep- 

 tion to this. The sexual instincts of the green frogs are excited 

 even in winter when the frogs are fed. Also, on occasions, Rana 

 pipiens and Rana onca will snap at the head of a companion frog 

 who has taken a worm that he^ was trying to capture. Whether 

 this is an exhibition of anger, or the frog is still trying to get 

 the moving worm which is gradually disappearing and finally 

 disappears in the other frog's mouth, is a question not easily 

 settled. Judging from the general meekness of toads and frogs, 

 it would seem more probable that the latter explanation is the 

 correct one. 



XII. Geographical Distribution. 



The Tailless Batrachians are widely distributed. Toads, or 

 representatives of the genus Bufo (about 100 species), are 

 found all over the world except in Australia and Madagascar. 

 The genus Hyla, the largest among the Salientia (150 species), 

 is almost cosmopolitan in its distribution, being found every- 

 where except in Africa. The genus Rana (140 species) has a 

 range extending all over the northern world, though it is prac- 

 tically lacking from Australia, Africa, and South America. 



Most of the North American Salientia belong to these three 

 genera, Bufo, Hyla, and Rana. There are only four genera 

 (Ascaplus, Scaphiopus, Acris, and Clorophilus ') peculiar to the 

 continent, and of these, two (Ascaplus and Acris) possess a single 

 species each, and one of these (Ascaplus) has, as far as known, 

 an unusually limited range. 



1 chorophilus has one representative in the Neotropical realm (Peru). 



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