r.-I). 17 W,\TKR-Ni:-,VT. 



GO KXAMru.s OF >NM:CTION BI:TWI;I.N CLACKS. 



with a hard, horny .-kin, that reminds us of the .-hell of the 

 Turtle; and we ha vein . . . / 



the ponds and ditches 

 of our own country 

 more than one species 

 of the Water-newt, 

 (Fig. 17), which has 

 the furmof the .Lizard, 



whilst, in its metamorphosis and internal structure, it corresponds 

 with the Frog. Amonir the Lizards, again, there is a tribe that 



is characterised by its 

 flattened body and 

 Frog-like form. One 

 species of these is seen 

 in Fig. ](} ; but there 

 are others, in which 

 the tail is shorter, and 



the bodv broader, so as still more to resemble that of a Fro^. 

 Thus, we have not only the connecting link of the Lizard-like 

 Frocr. but of the Frog-like Lizard ; the essential characters of one 

 of the groups hcin^ preserved in each case, but displayed under 

 the form of the other. 



4 1 . Of a complete series 

 of transitional forms be- 

 tween i\\o classes, moreover, 

 we have a beautiful instance 

 in the case of Reptiles and 

 Fishes. One of these tran- 

 sitions is established by the 

 metamorphosis of the Frog 

 tribe already adverted to (> ; If>) ; but the connection is shown 

 ;n-o in certain species, which, even in their adult state, possess 

 both luii'js and 'jills, and which have the whole of their conforma- 

 tion intermediate between that of the true Fi-hes and that of 

 "Reptiles. Of this kind are the A.r<J<>ll ( Fig. 19), which is undoubt- 

 edly a Reptile, since the characters of the Reptile predo- 



!';;. 1'.). -Ax. 



