26o 



DISCOVERY REPORTS 



in the dry skull ; the pointed posterior end of the broken frontal projected from the line 

 of the skull when fresh, and the edges of the bones show signs of regeneration ; there is 

 a place on the crown where a fragment of the left parietal has been pushed down 

 below the level of the rest of the bone and has fused in that position, but there were 

 no skin markings to indicate the exact nature of the agency which produced such 



injuries. 



Even if it were necessary it would be very difficult to avoid the belief that the ferocity 

 of Hydrurga is one of the reasons for its solitary mode of life, but it may also be a re- 

 flection of another of its characteristics, one unique among the Pinnipedia, that of bemg 

 a carnivore of large appetite and catholic taste. Besides being an eater of fish and 

 cephalopods it is well known as a principal enemy of the penguins. Levick (191 5) has 

 well described the seal's habit of lying in wait at penguin jumping-off places. R. N. R. 

 Brown (1906) records the snatching of a penguin from a piece of ice, and I have myself 

 seen it run down and catch a ringed penguin in open water, an impressive demon- 

 stration of the speed of the mammal. Penguins are roughly shaken from their skins, 

 but a great deal of skin and feathers is swallowed ; the faeces of animals which have 

 been feeding on penguins are almost entirely composed of feathers. Other birds, e.g. 

 Macronectes and Pelecanoides, are taken if opportunity offers. 



This species has frequently been seen feeding on the carcasses of whales and seals 

 killed in the south. If large fragments are attacked pieces are grasped with the teeth 

 and torn off by rotary movements. 



Hydrurga quite commonly feeds on other seals but not, so far as is known, on its 

 own kind; Mawson (191 5) records having seen a Weddell seal eaten, and the chase 

 of a crab-eater, which after several narrow escapes took refuge on an ice-foot. This 

 was not necessarily safe : I was once called on deck in the pack to see a leopard seal 

 which had jumped on to an ice-cake and attacked a crab-eater there. When I came 

 out the leopard seal had disappeared but the prey had been torn open and killed, the 

 ice as well as the carcass being smothered in fresh blood. A preference is shown for 

 the softer parts of other seals, blubber, guts, etc. 



The results of the examination of the stomach and gut contents of thirty-two animals 

 are recorded by the following: Gray, 1844, i; Ross, 1847, i ; E. A. Wilson, 1907, 2; 

 Bruce, 191 5, 7 ; G. C. L. Bertram, MS., 6 ; J. E. Hamilton, subter, 15. They are as follows: 



