36 EDWARD A. WILSON. 
One would have no doubt, judging merely from its outward appearance, that it 
had some need for a far greater agility than Weddell’s Seal, and this is shown when 
the animal is disturbed, first in attack and then in flight. In attacking man or dogs, 
it rushes forward first with open mouth and a husky roar, and. then as quickly makes 
off for the nearest hole to reach the water. In character, as in appearance, Lobodon is 
the most active of all the Antarctic seals on land or ice, but probably is inferior 
to the others in point of speed while under water. It is usually aggressive when 
disturbed, and, in comparison with Leptonychotes, might certainly be called “ neurotic.” 
Its progression on ice is far more rapid than that of Weddell’s seal, and its 
movements when alarmed become as nearly as possible quadrupedal ; for while the lithe 
and active body takes on the motion of a fish, the fore limbs, instead of lying idle along 
the sides, as in Weddell’s Seal, assume an alternating action, exactly as they would in a 
four-legged beast. The hind limbs, of course, are functionless as legs, and cannot be 
brought forward as those of the Hared Seals can; but the rapid movement of Lobedon 
when thoroughly alarmed, rushing along as it doves with head erect in a sinuous, 
snake-like course, is strongly suggestive of some fairly recent four-legged antecedent. 
It has, of course, also the characteristic ‘“ looper-like ” method of progression, in which 
the body is alternately hitched up and shot forward from the chest and pubes, and 
this method it has in common with Weddell’s Seal. The other mode of pro- 
gression seems peculiar to itself. In the water it is naturally more active still, and 
this activity is probably needful to it, more for escaping from its arch-enemy, the 
Killer Whale, than for procuring food. 
As Captain Barrett Hamilton has pointed out, the long, pig-like snout and the 
peculiar character of its teeth, which close upon one another to form a sieve, have both 
to do with its method of capturing the crustaceans (mainly Luphausi#) upon which 
it feeds. Hither at the bottom of shallow seas, or along the “foot” or submerged 
ledges of bergs and floes, it stirs up both mud and grit and gravel, taking these in 
freely with the crustaceans that are stirred up with them. The arrangement of the 
cusps in the teeth of both jaws, then coming into play, allows the water to drain out 
before the remaining contents of the mouth are swallowed. This development of 
cusps in the teeth of the Lobodon is probably a more perfect adaptation to this purpose 
than in any other mammal, and has been produced at the cost of all usefulness in the 
teeth as grinders. The grit, however, which forms a fairly constant part of the contents 
of the stomach and intestines, serves, no doubt, to grind up the shells of the crusta- 
ceans, and in this way the necessity for grinders is completely obviated. 
In a few rare cases there is seen to be some wear, however, in the teeth, and 
this always in the skulls of the oldest seals. Such wear is not easily accounted for, 
but may follow, I think, from some change of habit or of diet in old age, perhaps, as 
in Weddell’s Seal, from opening ice-holes in a secluded bay, or from changing to a 
seaweed diet, as above suggested. The delicate nature of the cusps, one might 
think, would lead to frequent damage, but this is not the case; and though it is 
