AMPHIBIOUS QUADRUPEDS. 243 



both sides, and are friends to neither, so between 

 terrestrial and aquatic animals there are tribes 

 that can scarcely be referred to any rank, but 

 lead an amphibious life between them. Some- 

 times in water, sometimes on land, they seem fit- 

 ted for each element, and yet completely adapted 

 to neither. Wanting the agility of quadrupeds 

 upon land, and the perseverance of fishes in the 

 deep, the variety of their powers only seems to 

 diminish their force ; and, though possessed of 

 two different methods of living, they are more in- 

 conveniently provided than such as have but one. 

 All quadrupeds of this kind, though covered 

 with hair in the usual manner, are furnished with 

 membranes between the toes, which assist their 

 motion in the water. Their paws are broad, and 

 their legs short, by which they are more complete- 

 ly fitted for swimming, for, taking short strokes 

 at a time, they make them oftener and with greater 

 rapidity. Some, however, of these animals are 

 more adapted to live in the water than others ; 

 but, as their power increases to live in the deep, 

 their unfitness for living upon land increases in 

 the same proportion. Some, like the otter, re- 

 semble quadrupeds in every thing except in being 

 in some measure web-footed ; others depart still 

 further, in being, like the beaver, not only web- 

 footed, but having the tail covered with scales, 

 like those of a fish. Others depart yet farther, 

 as the seal and the morse, by having the hind-feet 

 stuck to the body like fins; and others, as the 

 lamentin, almost entirely resemble fishes, by hav- 

 ing no hind-feet whatsoever. Such are the gra- 



