FOSSIL OTARIES 217 



Seals, three are southern and one only is northern, but the 

 three southern are closely related (perhaps doubtfully distinct, 

 at least two of them), and are evidently recent and but slightly 

 differentiated forms of a common ancestral stock. Of the two 

 Eared Seals of largest size (Eumetopias stelleri and Otaria ju- 

 bata), one is northern and the other southern, and, though dif- 

 fering generically in the structure of the skull, are very similar 

 in external characters, and geographically are strictly represent- 

 ative. Zalophus is the only genus occurring on both sides of 

 the equator, but the species are different in the two hemispheres.* 

 The Fur Seals of the north are the strict geographical repre- 

 sentatives of those of the south. Phocarctos hookeri is Austral- 

 asian, and has no corresponding form in the Northern Hemi- 

 sphere. No species of Eared Seal is known from the North 

 Atlantic. Several of the southern species range northward 

 into the equatorial regions, reaching the Galapagos Islands and 

 the northern shores of Australia. 



FOSSIL OTARIES. 



The only fossil remains unquestionably referable to the Ota- 

 ries are those found by Dr. Haastt in the Moa Caves of New 

 .Zealand. These have been referred by Dr. Haast to the species 

 of Eared Seals still inhabiting the New Zealand coast. J Hence 

 no fossil remains have thus far been discovered outside of the 

 present habitat of the group, their supposed occurrence in the 

 Tertiary formations of Europe requiring confirmation. The 

 absence of the Otariidcc from the North Atlantic renders any 



* This statement is made with some reservation, owing to the fact that 

 it is not quite clear what the species are that are found in the Japan Seas. 

 Both Eumetopias stelleri and Callorhinus ursinus extend southward, appa- 

 rently in small numbers, along the east coast of Asia to Japan. Zalophus 

 lobatus has been accredited to Japan, but apparently on the basis of Tem- 

 minck's Oiaria stelleri, which is evidently a composite species, which has been 

 referred, at different times, in part to Z. lobatus and Z. californianus ((j'tl- 

 lespii, auct. ). The latter has as yet been certainly found nowhere except 011 

 the Pacific coast of the United States, and Z. lobatus has not been positively 

 identified from any point north of Australia. Temminck's figures 1-4, pi. xxii ? 

 of the Fauna Japonica, seem unquestionably to represent skulls of Zalophus, 

 but whether the Australian or the Californian species, or a third, as yet un- 

 named, is apparently by no means settled. If it proves to be the Z. lobatus, 

 it forms an exceptional case of the same species occurring on both sides of 

 the equator. 



t Nature, vol. xiv, pp. 517, 518, Oct. 26, 1876. 



IDr. Haast identifies them as "Arctocephalus lobatus (?) and A. cincreus" 

 and "Gypsophoca tropicalis." 



