90 Dr. Burmeister on Arctocephalus Hookeri. 



and under this title I have introduced it in the list of Mammals 

 of the country published in the ' Anales/ tom. i. p. 464. no, 168 ; 

 but since then, the skull having been more perfectly cleaned, 

 and the body of the animal set up in its proper shape, I have 

 observed that it is not very different from the other specimens of 

 Otanafuhata s. leonina preserved in our museum. On studying 

 the animal with greater attention, I saw that it was nothing else 

 than a young male of this species, and that the Arctocephalus 

 Hookeri of Gray represents a distinct species, and is in no 

 manner the young state of Otaria juhata, although by its ex- 

 ternal appearance the young Otaria juhata resembles a good 

 deal Arctocephalus Hookeri. 



Externally, the length of the ears is a marked character, 

 being much larger (0'030 m^tre in place of 0"015) in A. Hookeri. 

 Then the two species may be distinguished by the fore flippers, 

 which have no nails in any of the specimens of Otaria juhata 

 that we have in our collection, although Gray figures them 

 distinctly in his Arctocephalus Hookeri (pi. xiv.). 



The posterior flippers, also, are different. Gray figures five 

 claws on them, describing the second and third nails as the 

 larger, the fourth and fifth as less, and the first as the smallest. 

 Our specimens of Otaria juhata have three nails very large 

 (lj-l| inch), the middle one of them the largest, and the 

 others (the first and fifth) generally wanting; or if they are 

 present, they are very small, scarcely visible, one line broad ; 

 the fifth is almost always wanting. 



Lastly, the young males, which in shape and colour very 

 much resemble Arctocephalus Hookeri ^ have a large dusky- 

 yellow blotch about the eyes, which is wanting in Arctoce- 

 phalus^ and which appears very characteristic of the young 

 Otaria juhata. 



The skull shows other diflerences : it is more depressed in 

 Arct. Hookeri in comparison with its length ; and the anterior 

 part, which corresponds with the mandibles, is relatively 

 larger. The Arctocephalus has much smaller teeth than indi- 

 viduals of the same size of Otaria juhata ; but the lateral 

 tubercles of the crown of the molars are much larger. 



Lastly, the shape of the " palate " is very different : its 

 hinder portion is much narrower and shorter in Arctocephalus 

 Hookeri J the posterior margin of the '•' palate " of Otaria juhata 

 being shown almost to the anterior margin of the glenoid 

 cavity for the inferior mandible ; whilst in Ar-ctocephalus 

 Hookeri this margin does not pass beyond the posterior 

 angle springing from above the zygomatic arch. This 

 character is constant in every age of the animals, being pre- 

 sent even in the skull of a recently born Otai-ia juhata in 



