FROGS. 239 



large masses ; they are fertilized externally, in 

 the process of deposition, which always takes 

 place in the water. 



The head of these animals is very large, but 

 the cavity of the skull is very small ; and yet 

 the brain is scarcely sufficient to fill it. The 

 gape is enormous. 



The Anoura are distributed over the whole 

 habitable globe ; but they abound most in 

 America, while Africa presents us with very 

 few. These facts are sufficiently explained by 

 the abundance of water in the one continent, and 

 by the scarcity of it in the other. The Order 

 contains four Families, Ranadce, Hyladce, Bufo- 

 nidce, and PipadcE, 



Family I. Ranad^. 



{Frogs.) 



The Frogs proper are distinguished from the 

 Toads by having small teeth in the upper jaw ; 

 most of the species have also teeth in the palate, 

 or rather pointed processes forming a part of the 

 bones to which they are attached, as in the case 

 of certain fishes. From the Tree-frogs they are 

 distinguished by having the toes ending in blunt 

 points, scarcely or not at all dilated, and by 

 terrestrial and aquatic habits. They have always 

 four toes on each anterior foot, and five on the 

 posterior, which are commonly united by a broad 

 swimming membrane, like those of web-footed 

 birds. At the base of the first finger of the hand, 

 there is generally a prominence, more or less 

 obvious, which proves, on dissection, to be the 



