OEDEE OF AMPHIBIA. 
Taken in tlie strictest sense of the word, the denomination of 
Amphibia (a/i^l, on all sides ; fiiog, life) ought to he applied only 
to those animals which can pass their existence in the air or in the 
water alternately : such as the Batracbians, 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 pisci/orm 
— 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 most aquatic quadrupeds ; on the contrary, 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 Pinnigrada, proposed by the late Professor 
De Plain ville, who places it as one of the principal divisions of the ordinary Carnivora. 
— Ed. 
f These remarks apply more to the true Phocidce or Seals, than to the Sea-bears 
or the Walrus, both of which latter bring the 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 quadrupedal, 
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 more 
H 
