18/2.J DR. J. E. GRAY ON SEA-BEARS. 661 



alveolar edge. The skull has the fifth grinder behind the back edge 

 of the front part of the zygomatic arch. The only Seals that I know 

 that have the teeth in this position have six grinders in the upper 

 jaw ; and they, like this genus, all have triangular-shaped grinders 

 and abundant under-fur. 



Br. Peters in his second paper on Eared Seals, ' Mouatsbericht,' 

 1866, p. 671, enlarges his subgenus Aretophoca, and also refers to it 

 Otaria falklandica of Shaw and Burmeister, which he says is my 

 Otaria nigrescens, from the unpublished figure of the skull of it 

 which I gave him, and which is a species of my restricted genus 

 Ar otocephalus, which has only the sixth upper tooth behind the front 

 of the zygomatic arch. 



Dr. Philippi sent a description and figure of a skull that he had 

 received from the island of Masafuera, on the west coast of South 

 America, which is published by Dr. Peters in the ' Mouatsbericht ' 

 for 1871, p. 588, t. 1, 2, and which he calls Aretophoca aryentata. 

 This skull wants the hinder part of the brain-case, has six grinders in 

 its upper jaw, and is in every respect very like the skull of Gypso- 

 phoca tropicalis and the Aretophoca philippii from Juan Fernandez. 

 It chiefly differs from the figure of the latter skull, as Dr. Philippi 

 shows in his plate, in the hinder portion of it being narrower, and the 

 condyles much shorter or rather narrower. 



These three skulls appear to me to belong to one group ; but whether 

 they are three distinct species (two from the west coast of South 

 America, and one from North Australia) I will not attempt to deter- 

 mine, as I have only seen the skins and skull of the one from the 

 latter region ; but they are all Fur-Seals and may be distinct. 



Dr. Philippi proposes to enlarge the genus Aretophoca, and refers 

 to it four species, which he thus characterizes : — 



" 1. Aretophoca falklandica, Shaw, Gray, Burmeister. Grau, mit 

 bias rother Unterwolle. Atlantischer Ocean. 



"2. A. niyrescens, Gray. Schwiirzlich, mit dunkel rostrother Un- 

 terwolle. Atlantischer Ocean. 



"3. A. aryentata, Philippi. Grau, mit bias rother Unterwolle. 

 Stiller Ocean. 



"4. A. philippii, Peters. Schwarzlich, mit dunkel rostrother Un- 

 terwolle. Stiller Ocean." 



If A. falklandica is my Arctocephalus falklandica, I have never 

 seen its skull and do not know the position of its teeth. 



A. niyrescens has the sixth upper grinder behind the back edge of 

 the zygomatic arch, and belongs to my restricted genus Arctocephalus, 

 in common with A. antarctica of the Cape, which is F. Cuvier's type 

 of the genus, and A. cinereus of Quoy and Gaimard, of New Holland 

 and New Zealand. A. aryentata and A. philippii have the fifth and 

 sixth upper grinders behind the back edge of the zygomatic arch, 

 and, I believe, are both referable to the genus Gypsophoca. 



The figures of the skulls of Otaria philippii and of Otaria ar- 

 yentata have the front edge of the hinder aperture of the nostrils 

 with a triangular slit in the middle ; the young skull of Gypsophoca 

 tropicalis has it truncated and entire; but this part, as I have 



