GENERAL HISTORY. 253 



from San Francisco, Cal., labelled by the collector, Dr. Ayres, 

 as " 3 or 4 days old," shows distinctly the alveoli of the milk 

 dentition, with the permanent molars, five in number, just 

 cutting the gum. The last (fifth) upper molar is placed but 

 little further from the fourth than the fourth is from the third. 

 The broader space between the foiu-th and fifth molars is al- 

 ready indicated, but is, even relatively, much less than in the 

 adults. The last molar stands close to the end of the maxilla, 

 and hence has the same relative position at this early i^eriod 

 that it has in old age. As the size of the skull increases, how- 

 ever, the space between the fourth and fifth molars becomes en- 

 larged. Dr. Gray says that in a " foetal skull " of this species 

 " from California the hind upi^er grinder is at a considerable 

 distance from the others, as in the very old skull in the [British] 

 Museum and the two adult skulls figured by Mr. Allen ; but 

 there is to be observed on each side a concavity in the place of 

 the fifth grinder on the right side it is a shallow, small cavity 

 which has enclosed a rudimentary tooth ;* on the other side the 

 concavity is larger, but not so evidently the cavity for atooth.t" 



As is well known, the Otaria stelleri of Temminck's " Fauna 

 Japonica" is a Zalophus (at least in part).| 



Since the publication of my i)aper on the Eared Seals, in 1870, 

 our knowledge of this species has greatly increased, mainly 

 through the published observations of Captain Scamraou and 

 Mr. H. W. Elliott. Captain Scammon, however, seems to have 

 not distinguished the two species occurring in California, since 

 he gives no distinct account of the smaller Californian species, 

 although he appears to have given measurements of a female 

 of the latter, and evidently blends, in a general way, the history 

 of the two. Mr. Elliott has not only published a very full 

 account of its habits, as observed by him during several years^ 

 residence at Saint Paul's Island, but also a most admirable 

 series of sketches of the animals, drawn from life. In the fol- 



*As already stated, Dr. Gray appears to have believed that the last or 

 fifth grinder is homologically the sixth, because it hastwo roots, and that the 

 fifth is deciduous, a theory I believe unsupported. Was not the small cav- 

 ity he here refers to as having enclosed a tooth merely the alveolus of the 

 last milk molar, which I have found to occupy just this position ? Dr. Gray 

 himself, in previously referring to the same skull, alludes to " a small pit" 

 " at the back edge of the fourth grinder," "from which no doubt a small 

 rudimentary tooth has fallen out." Suppl. Cat. Seals and Whales, pp. 29, 30. 



t Hand-List of Seals, p. 41. 



tFor further remarks on " Otaria stelleri" Temminck see infra, under Za- 

 lophus californianus. 



