EXAMPLES OF CONNECTION BETWEEN 



5) 



or altogether wanting, of which the common Blind-worm or 

 Slow-worm of this country is a 

 characteristic example ; for so 

 completely does it blend the ex- 

 ternal characters of the Lizard 

 and Serpent tribes, that it has 

 been placed by some Zoologists 

 in one, and by some in the other. 

 With the Frog tribe the class 

 of Serpents is connected by n 

 very interesting animal the 

 Cfecilia, or Blind Snake ; which 

 has the general form of the 

 snake tribe, but which, in fact 

 really belongs to the class 

 Batrachia, having a skin des- 

 titute of scales, and being 

 found to undergo a metamorphosis, having at one period (like 

 the Frog, &c.) the same form of the circulating and respiratory 

 organs as the Fish. 



FIG. 15. XAIA I.'AJK. 



Fiu. 1C. CHAI 



40. But the class Batrachia is not connected with the other 

 tribes of Reptiles by one link of transition only ; for it contains 

 animals which may be regarded as representing the Turtles and 

 Lizards in its own group, just as the Bats represent Birds, and 

 the Whales represent Fishes, among the Mammalia. Thus, 

 there is a species of Frog in South America, whose back is covered 



