AltlMALS 375 



I 



CHAP. V. 



OF AMPHIBIOUS QUADRUPEDS. 



The gradations of nature, from one class of beings to anotlier, 

 are made by imperceptible deviations. As we saw in the fore- 

 going chapters, quadriipeds^lmost degraded into the insect tribe, 

 or mounted among the inhabitants of the air, we are at present 

 to observe their approach to fishes, to trace the degrees by which 

 they become more unlike terrestrial animals, till the similitude 

 of the tish prevails over that of the quadruped. 



As in opposite armies the two bodies are distinct and separated 

 from each other, while yet between them are various troops that 

 plunder on 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. Sometimes in water, sometimes on land, they seem fitted 

 for each element, and yet completely adapted to neither. Want- 

 ing the agility of quadrupeds upon land, and the perseverance of 

 fishes in the deep, the variety of their powers only seems to di- 

 minish their force ; and, though possessed of two different me- 

 thods of living, they are more inconveniently 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 completely 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, resemble 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 re- 

 semble fishes, by having no hind feet whatsoever. Such are the 



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