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Show 494 DR. ST. G. MIVART ON THE PINNIPEDIA. [May 19, only a faint indication of the groove which so deeply divides it the tympanic in Phoca. I could detect no glenoid foramen. The basis cranii is but little curved antero-posteriorly, convex downwards. There is a large crista galli, but a small cerebellar process to the petrosal. The condyloid foramen is larger and nearer the condyle than in any of the genera hitherto noticed, and indeed than in any other Pinniped. The zygomata are small, projecting much outwards at the glenoid surface, and thence sloping inwards and forwards. The mandible shows a faint trace of a subangular process. The angle itself is placed very high up and is rather inflected. Young dentition:-I. % C. \ P. 4, M . I. ° 3 l' 4' 0 Usual adult dentition : - 1 . J, C. \, P. |, M . 5=18. The enormous tusks and perfect simplicity and similarity of the other teeth, each with a flat grinding surface, have been again and again described. Otaria **.-According to Allen there are nine species of Otaries, which he arranges in six genera. Of these species the first and seventh come from the Galapagos and both coasts of South America ; the second from the Auckland Islands; the third and sixth from both shores of the North Pacific ; the fourth from California; the fifth from the Australian Seas ; the eighth from the Cape of Good Hope ; and the ninth from Australia, New Zealand, and the Antarctic Seas. The Otaries turn the hind limbs forwards, and have a small external ear and also a scrotum, as is well known. The palmar and plantar surfaces are naked. The eyes are large. The nails are small or rudimentary, except those of the three middle digits of the pes. There are 15 dorsal, 5 lumbar, 3 or 4 sacral, and 8-14 caudal vertebrae. The skull has the anterior nares more vertical and nearer the anterior end of the skull than in the Seals. Otherwise the skull resembles that of Phoca, except in the following points:-There is a well-developed frontal postorbital process, and the postorbital process of the zygoma is formed by the malar only. There are no defects of ossification in the basioccipital and hardly any in the ex-occipital ; but there may be in the basisphenoid and in the place of the jugular and condyloid foramina. The petrotympanic is not bullate, but rugged and irregular, and the course of the carotid artery is plainly indicated along its inner border and is covered in beneath by a rather slight and imperfect ossification. The surface 1 See Schreber, Fortg. Wagner, vii. p. 51; Peron, Voy. Terres Aust. ii. p. 4; Steller, Nov. Coram. Petrop. ii.; Nilsson, Vet.-Akad. Handl. (1837); Buffon, xiii. p. 53; Supp. vi. pp. 47, 48, 49 ; Cook's Second Voy. ii. p. 203 ; Quoy et Gaimard, Voy. Astrolabe, Mamm., and Zool. Uranie; Forster, Voy. round the World, ii. ; Gray, Erebus and Terror, Cat. Seals Brit, Mus. (1866) p. 44; Clark, P. Z. S. 1873, p. 750, 1875, p. 650, 1878, p. 371, 1884, p. 189; Temminck, Fauna Japonica; Murie, Trans. Zool. Soc. vol. viii. p. 501; Gervais, Hist. Nat. Mamm. ii. p. 305 ; and especially Allen, N. Amer. Pinnipeds, p. 187. |