l6 EXPÉDITION ANTARCTIQUE BELGE 



(b) The skeleton lias been described in détail by Owen in the Catalogue of the Osteo- 

 logical Muséum of the Royal Collège of Surgeons of London, p. 642 and in the Annals and 

 Magazine of Natural History for 1843 at page 33 1. 



(c) Externally, in the dimensions and proportions of its limbs and tail as well as in the 

 size and number of its claws, this seal bears a close resemblance to Leptonychotes. Its head, 

 however although not so blunt as that of Ommatophoca is thicker than that of Leptonychotes. 

 But the colour is the most distinctive feature of the animal, since it is at ail âges far lighter 

 than that of any of the other species found in Antarctic seas. As to the exact hues and patterns 

 we are, however, still in some doubt, which can only be dispelled by a detailed description of 

 the living animal written by a compétent field-naturalist. The original describers designate the 

 pelage as « brun olive, parsemé çà et là, en dessus, aussi bien qu'en dessous, de grandes plaques 

 de couleur jaunâtre, » a description with is borne out by the plate (no. 10). The skins collected 

 by the Belgica are, however, nearly white with only indistinct traces of mottling. In life 

 they were, according to Monsieur Racovitza, « d'un blanc pelucheux à reflet verdàtre. « On the 

 other hand Mr. W. S. Bruce (') ( 2 ), who took a voyage to the Antarctic on the steamship 

 Balaena, alludes to this species as a « creamy white seal with a darker dorsal stripe » Lastly 

 the skins in the British Muséum show that a good deal of mottling may be présent in immature 

 spécimens. On the whole I suspect that the crab-eating seal gets whiter as it grows older. 



Ross's seal might possibly be confused with this species, but lias the head blunter and the 

 colour darker. 



Habits and Habitat : — The Belgian Expédition found Lobodon the most fréquent 

 species on the pack-ice. It was also présent with Leptonychotes in the Strait of Gerlache in the 

 Palmer Archipelago. On being approached it showed a great anxiety to make its visitors 

 acquainted with its dental armature, displaying its teeth and « en soufflant violemment par les 

 narines ». A species of Euphausia forms its habituai nourishment. « Il nage la bouche ouverte 

 dans les bancs de ces crustacés, à la façon des baleines, et en consomme de grandes quantités. » 

 The young are brought forth on the pack-ice in September and, already of a considérable size, 

 are clothed with a thicker coat than that of their parents. « La mère allaite quelques jours seule- 

 ment son enfant; elle le laisse ensuite se débrouiller tout seul. » 



Monsieur Racovitza's description of the method of feeding of this seal is interesting and 

 I think it very probable that some light is thus thrown upon the wearing and use of the extraor- 

 dinarily complicated cheek-teeth, the cusps of which may form a sieve through which is strained 

 the water taken into the moût h with the Euphausia. At ail events their shape is not that of 

 instruments used much for mastication, a process which would rapidly show itself by their 

 detrition in a far more marked manner than is actually the case. If my supposition be correct 

 we hâve hère a remarkable parallel to the baleen of the whale-bone whales. 



(1) Report of the sixty-third meeting of the British Association for the Advancement of Science held at 



: [8g3, p. 807, 1894. 



(2) Proceedings of the Royal Physical Society of Edinburgh, vol. xu, p. 35o, 1894. 



