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ORDER X. PACHYDERMATA. 



284. The order Pacliydermata, which includes all the 

 ungulated or hoofed true Mammalia that do not ruminate, 

 derives its name from the thickness of the skin, which is usually 

 so remarkable a character of the animals it comprehends, as 

 for instance, in the Elephant, Hippopotamus, Rhinoceros, and 

 common Hog. A very cursory glance through the group of 

 animals thus brought together, serves to show that they are not 

 by any means so closely allied, as are those of the preceding 

 order. The Elephant, the Horse, and the Hog, for example, 

 differ so much from one another, that we might be almost led to 

 regard them as types of distinct orders; or at any rate we should 

 be forced to suppose that the continuity or completeness of the 

 series had been broken into. The interruption of the chain 

 becomes still more striking, when we pass from any of the 

 animals already named, to the Dugong and other Whale-like 

 species, which many distinguished Naturalists have arranged in 

 the same order. But the researches which have been made, for 

 some time past, into the structure of the animals that formerly 

 covered our globe, as made known by their fossil remains, have 

 been peculiarly successful in their results as regards this order ; 

 furnishing, in a large proportion of cases, the very forms which 

 are wanting as links in the chain, and which, when placed in 

 their proper position, give order and completeness to that, which 

 previously seemed a confused assemblage of dissimilar creatures : 

 whilst the animals to which these remains belonged, have their 

 strange forms accounted for, and their striking peculiarities ex- 

 plained, when they are viewed as the intermediate links between 

 groups, which, as known only by the animals at present existing, 

 seem far apart from each other. 



285. For the reasons just specified, it is impossible to assign 

 any other general character to the order, than those which have 

 been already given. The conformation of the teeth, and the 

 structure of the extremities, which elsewhere afford such import- 



