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Show 486 DR. ST. G. MIVART ON THE PINNIPEDIA. [May 19, distinct suborder, the iEluroid, Cynoid, and Arctoid Carnivora being united to form the other suborder. I think moreover that there is not the slightest question that their cranial characters indicate most strongly their approximation to the Arctoid type, as has often been noticed before on other grounds (De Blainville says, ' Les Ours, dont les rapports avec les Phoques ont ete sentis de tout temps et m e m e par Aristote,' Osteographie, tome ii. p. 49). Indeed their skulls seem to be simply a further modification of this type, showing resemblances to the true Bears on the one hand, and the Otters on the other." Before stating m y own general conclusions, I will proceed to give my notes upon the various genera of Pinnipeds. Phoca1.-This genus consists of half-a-dozen or a few more species, confined to the northern arctic and temperate regions of the Old aud New "Worlds, including the Aral and Caspian Seas and the coasts of Japan. P. vitulina is found in both hemispheres. They have the paims and soles hairy, five well-developed claws to each foot, those of the manus being the broader and more curved. The hind limbs are constantly extended backwards, and cannot be turned forwards. There is no external ear and no scrotum. The toes of the pes do not differ quietly in length, the first and fifth not greatly exceeding the others. There are 14 or 15 dorsal, 5 lumbar, 4 sacral, and from 11 to 15 caudal vertebrae. The skull presents the following general characters :- The premaxilla is much separated from the frontal by a more or less wide junction of the nasal with the maxilla. The nasals are not generally, if at all, anchylosed together, and they join the premaxillae. There is no lachrymal foramen. The infraorbital foramen is of moderate size, or rather large. There is no distinct foramen rotundum, one opening representing both it and the spheno-orbital fissure. Sometimes there are defects of ossification between the basisphenoid, alisphenoid, aud pterygoid. There are one or two large openings in the palatine, representing the spheno-palatine foramen, with defects of ossification above it between the frontal, maxilla, and palatine. There are also, generally, defects of ossification in the basisphenoid and basioccipital. The alisphenoid is joined by a long descending process of the parietal. There is no postorbital process from the frontal, and the zygomatic postorbital process is formed partly by the malar and partly by the squamosal. There is a large crista galli. The cerebellar fossa of the petrosal is very deep. The bulla is dense and undivided, traversed by a carotid canal the posterior aperture of which is on the hinder surface of the bulla. There is, in most cases, hardly any paroccipital process. The mastoid is prominent and forms an outwardly directed 1 Linn. Fn. Suec. ii. p. 2, 4; Syst. Nat. 12, i. p. 56; Schreb. Saug. vol. vii. p. 17; Buffon, Hist. Nat. xiii. p. 333, pi. 45, and Suppl. vi. pi. 46; Gray (Calloccphalus, Pagomys, Pagophilus, Halicyon, and Phoca), Catalogue of Seals and Whales in Brit. Mus. pp. 20-32 ; J. J. Allen, North Amer. Pinnipeds, pp. 412, 557, &c.; De Blainville, Osteog., Phoca; Cuvier, Ossem. Foss., Atlas, vol. ii. pi. 219. |