OEDEE OF AMPHIBIA. 



Taken in the strictest sense of tlie word, the denomination of 

 Amphibia («/j^i, on all sides ; j3ioe, life) ought to be applied only 

 to those animals which can pass their existence in the air or in the 

 water alternately : such as the Batrachians, which breathe, now in 

 the water, by means of gills, and then in the air, by lungs. But 

 this expression has been altered from its true meaning ; and 

 what are now more especially called Amphibia are those Mam- 

 malia which are essentially organized for aquatic life and which 

 can, with difficulty, move about on the land : such are the Morse 

 or Walrus, and the Seal.* 



The Morse or Walrus, and the various Seals, of which the order 

 of Amphibia is composed, present a series of characteristics which 

 correspond exactly with the mode of life which has devolved upon 

 them. They have the body elongated, cylindrical, and pmiform 

 — that is to say, representing that of a fish. Their limbs are very 

 short, the extremities alone being visible : these are converted 

 into fins by being provided with broad connecting webs. Their 

 anterior extremities hang along the body, and act backwards and 

 forwards, as in m.ost aquatic quadrupeds ; on the contrai'y, the 

 posterior extremities, stretched out in a horizontal and parallel 

 direction, are arranged in such a manner as to strike the water 

 obliquely.f Their furs are composed of a woolly, compact coat, 



* An appellation for this group is I'inmrjrada, proposed by the late Professor 

 Be Blainville, who places it as one of the principal divisions of the ordinary Ciiruia ra. 

 —Ed. 



t These remarks apply more to the true ThocidcB or Seals, than to the Sen-hears 

 or the Walrus, both of which latter bring tho hind-legs more forward when on 

 land than the Seals. When on land, the Seals wriggle themselves along by means 

 of the subcutaneous muscles of the body, making little use of their limbs while 

 on a flat or sloping surface. But the movements of the Sea-bears are quiidrupcdal, 

 and they not only make their way well upon land, but are excellent climbers of 

 rocks. They are also much swifter under the water than are the true Seals, as may 

 be commonly observed in the London Zoological Garden. The Walrus is far n^oro 



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