88 CLASSIFICATION OF AMPHIBIANS. 



this faculty of abstinence is limited. Out of three 

 toads shut up in sealed boxes by a French experi- 

 mentalist, one was found dead at the end of eighteen 

 months^ and the two others were in a very languid con- 

 dition — a clear proof that they would soon have shared 

 the fate of their companion. Until^ therefore, some of 

 these marvellous stories are authenticated by the testi- 

 mony of naturalists who have actually seen living toads 

 cut out of solid trees and stone walls^ we must with- 

 hold our belief from the fact, viewing all these narra- 

 tives as exaggerated representations of the possible case 

 we have just instanced. 



(94.) The sub-divisions of this order are not many, 

 originating in the comparatively few deviations from 

 the typical forms observed in the existing species. The 

 natural arrangement of all groups so situated is pecu- 

 harly difficult ; and, as their circular affinities have not 

 yet been investigated, we shall merely notice them in 

 the order in which they stand in the Regne Animal 

 of ]\I. Cuvier. The two principal divisions are the 

 frogs (^Ranidcs) and the toads {Bufoidce), both com- 

 prehending several smaller groups ; while, of those which 

 remain, the cell-backed toad (^Pipidce) is the most re- 

 markable. 



(95.) The Frogs (Ranidce) are chiefly distinguished 

 from the toads by the unusual length of the hind feet, 

 which are strong and well palmated : hence their great 

 power both of jumping and of swimming ; their skin 

 also is smooth, and there is not only a row of small fine 

 teeth round the upper jaw, but the palate also is fur- 

 nished with another range, placed transversely. It is 

 one of the many singularities attending these animals, 

 that while in the young or tadpole state they are herbi- 

 vorous, living only, according to Cuvier, upon aquatic 

 plants, yet no sooner do they effect their metamorphosis 

 than they become carnivorous, pursuing insects, slugs, 

 and similar animals, and feeding upon them whether alive 

 or dead. The eggs or spawn, as they are usually called, 



