FROGS AND TOADS 



more or less completely aquatic life. The frogs are more 

 aquatic than many toads. In external appearance 

 these amphibians differ mainly in colour, and in the 

 degree of wartiness or smoothness which they show. 

 It is plain that the most salient mark of difference from 

 the Urodela is the restricted tail and the fact that they 

 never possess in the adult condition either gills or gill 

 slits. Their fingers and toes, moreover, are never reduced 

 in number, and never, of course, vanish altogether as 

 they do in some of the snake-like Urodeles. 



THE SURINAM TOAD 



One of the very oddest productions in the frog line 

 is the Pipa americana. It is so flat that it seems almost 

 to consist of matter arranged in two dimensions only. The 

 head is small and the front edge of it garnished with 

 many little papillae. The toes end in star-shaped pro- 

 cesses, and the hind feet are webbed with unusual con- 

 spicuousness. The toad has got no teeth at all ; but 

 it makes up for this incapacity for offence by a consider- 

 able capacity for defence. Its body is covered with many 

 little poison glands, with which are sometimes associated 

 little spikes. Most persons have seen a young dog 

 rashly take into its mouth a common toad, and then 

 rapidly drop it ; this sudden change of intent is due 

 to the secretion by the toad of a poisonous liquid. The 

 Surinam toad possesses the same properties in a higher 

 degree. The flatness of this amphibian shows that it 

 is intended for a purely aquatic life ; and as a matter 

 of fact it does not leave the water. It is harboured in 

 pools in Guiana and perhaps in other parts of South 

 America. It has a method of attending to its young 

 that in all its details is unequalled in the frog tribe. 

 The common frog of this country, when it goes a- wooing, 

 leaves its offspring in the form of those masses of eggs 

 embedded in jelly which are familiar to everybody. 



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