14 Sotithern Cross. 



' Iklgica,' is certainly in keeping with the formidable cutting teeth 

 and massively developed cranial crests of this animal. The 

 Leopard-Seal may then be regarded as the true carnivore of the group, 

 subsisting on fish (and, when they can be obtained, birds), a prey 

 which needs both catching and holding. For such a role, requiring 

 both speed, strength and activity, besides its teeth, its elongated head 

 and body must be eminently suited. The three remaining genera 

 are more puzzling. In their case no difference of food or habits had, 

 until recently, been recorded. In spite of this I felt sure that the 

 differences of dentition must be correlated with differences of habit, 

 in however inconspicuous a degree. In Lobodon and Leptonycliotes 

 poorly developed cranial crests seem to indicate that no great violence 

 of jaw action is needed, a character in the second case supported by 

 the feeble dentition. In Lobodon the teeth, although actually not of 

 feeble size, are not of a shape which would lend itself to much use in 

 gnawing and grinding, and the small extent to which they are 

 actually worn down bears this out. It is then not easy to imagine 

 what can be the use of teeth so unique in zoology. Possibly their 

 formation may be explained by some words of Dr. Eacovitza. 

 His account of the feeding of Lobodon is as follows : — " Les 

 Eupliausia forment sa nourriture habituelle : il nage la bouche 

 ouverte dans les bancs de ces crustaces, a la fafon des Baleines, et en 

 consomme de grandes quantites." On reading these words I was at 

 once struck by the idea that the teeth of Lobodon might possibly 

 serve the animal as a sieve, whereby to rid its mouth of the water 

 taken in with the Euphausia, somewhat after the manner of baleen 

 in the Balacnidae. For this purpose the teeth seem to be exactly 

 suited. They do not fit closely, but alternate with those of the opposite 

 jaw so that the cusps form a perfect sieve. I believe, therefore^ 

 that the use of these extraordinary teeth is as I have suggested, and 

 I would direct the attention of zoologists who visit the Antarctic in 

 the future to what appears to be a point of great interest in the 

 life-history of this animal, and is, I believe, a hitherto unparalleled 

 function for the teeth of a mammal. Even if my supposition 

 prove incorrect, attention should ])e directed to the study of 

 Lobodon, with a view to throw light on the use of its teeth. At 

 all events, if extensively used for mastication, they would speedily 

 show the effects of wear and tear in a far more conspicuous manner 

 than they actually do. 



On the Antarctic pack-ice the food of LeptonycJiotes, like that of 

 Lobodon, is said to consist of Euphausia. Its teeth are utterly 

 different. I suggest that the form of the simple but not very 



