100 COMMON FROG. 



observed to practise. Its interior organs differ, if 

 closely inspected, from those of the future frog, 

 in many respects ; the intestines in particular are 

 always coiled into a flat spiral, in the manner of a 

 cable in miniature. 



Indeed the anatomy of these animals exhibits 

 so many singularities, that a volume might be 

 rilled with their history ; but the nature of a work 

 like the present forbids a detail of more than what 

 is necessary for a clear general idea of the animal 

 in its several states. When the tadpoles have ar- 

 rived at the age of about five or six weeks, the 

 hind legs make their appearance; gradually in- 

 creasing in length and size ; and, in about a fort- 

 night afterwards, or sometimes later, are succeeded 

 by the fore legs, which are indeed formed beneath 

 the skin much sooner, and are occasionally pro- 

 truded and again retracted by the animal through 

 a small foramen on each side of the breast, and 

 are not completely stretched forth till the time 

 just mentioned. The animal now bears a kind of 

 ambiguous appearance, partaking of the form of a 

 frog and a lizard. The tail at this period begins 

 to decrease ; at first very gradually, and at length 

 so rapidly as to become quite obliterated in the 

 space of a day or two afterwards. The animal 

 now ventures upon land, and is seen wandering 

 about the brinks of its parent waters, and some- 

 times in such multitudes as to cover a space of 

 iriany yards in extent. This is the phenomenon 

 which has so frequently embarrassed the minds 

 not only of the vulgar, but even of some superior 



