HANDS AND FINS 



in the series in possessing hands and feet, with fingers 

 and toes not exceeding five in number. In no fish, that 

 is or that was, is there the faintest trace of this penta- 

 dactyle limb . the fins are of a totally different nature, 

 and there is nothing that is in the least degree inter- 

 mediate between what has been termed the " icthyop- 

 terygium " or fish's fin and the " cheiropterygium " or 

 hand of the higher types. In this particular a verte- 

 brate animal is either a fish or it is not a fish. Further- 

 more, though some amphibians, the common English 

 newt for example, may appear to be like a fish in pos- 

 sessing fins along the back and so forth, there is this 

 important difference between the amphibian and the 

 fish fin, that the latter are supported by horny gristly 

 or bony rays which do not exist in the amphibian 

 fin. 



The existing amphibia may be readily divided into 

 three groups. Of these practically only two concern us 

 here, so that the third group may be summarily dealt 

 with. That group is the Apoda, and it consists of worm- 

 like amphibians which bear not a little resemblance 

 to the amphisbaenians among the lizards, and to the 

 typhlopidae among snakes, in that they burrow under- 

 ground and live upon worms and such like small game. 

 They are not suited for a life in menagerie, and have 

 never been on view at the Zoo. The two remaining 

 groups are known technically as the Urodela and the 

 Anura, and more popularly as frogs and newts the 

 tailless frogs being on that very account termed Anura. 



The Urodela are always well represented at the Zoo, 

 and we later draw attention to a number of different 

 types. We are here concerned merely with certain 

 generalities about the group. The most remarkable 

 fact about them perhaps is the tendency which 

 so many of them have to retain throughout life certain 

 of the characters of the larva. But as this matter is 



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