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Show 1885.] DR. ST. G. MIVART ON THE PINNIPEDIA. 491 the pterygoid, palatine, presphenoid, and basisphenoid. There is large paroccipital process and a considerable mastoid process. The meatus auditorius externus is prolonged well outwards, its lip is completed in front. The considerable palatine foramina are placed at about the antero-posterior middle of the palate. There is no angular process of the mandible near the condyle, but only a single process, which seems to correspond with the subangular process of those Seals which have both these processes. The coronoid process rises well above the mandibular condyle. Dentition:-I. J, C. \, P. * M . [=32. The molars are two-rooted except the first, which, with the last, is smaller than the others. The incisors are notched transversely on the inner side of the crown. The canines are large. The molars have strong conical crowns with only slightly developed accessory cusps from a strong cingulum, the inner part of which is well developed. All foregoing genera Monachus, Ommatophoca, Leptonyx, and Stenorhynchus agree together and differ from the genera Phoca and Halichoerus in having only four upper incisors ; nails of pes rudimentary or absent, and the first and fifth digits of that extremity greatly exceeding the others in length. The six genera then may be arranged in two groups thus respectively characterized and named Phocina and Stenorhynchina, as has been done by Professor Flower 1. Cystophora-'.-This genus of one species, of the North Atlantic and Arctic seas, is characterized by having the dorsal facial skin of the male capable of distension by the inflation of a sac which underlies it and is connected with the nostrils. The distended skin thus forms a sort of hood covering the dorsal part of the head. As in the Stenorhynchina, the first and fifth toes exceed the others. They also have prolonged cutaneous lobes. The nails are tolerably developed in all the extremities. There are 15 dorsal, 5 lumbar, 3 sacral, and 14 caudal vertebrae. In the skull the premaxillae do not rise to the nasals. The latter are small and not anchylosed together. The orbits are very large. The anterior nares are very wide, especially towards their upper part. The maxilla develops a small preorbital process. There is a large crista galli, but a small cerebellar fossa to the petrosal. There is a moderate-sized suborbital foramen, and there may he a deep fossa beneath or external to it, as is sometimes the case in P. grcenlandica. I have observed no defects of ossification between the pterygoid, palatine, and adjacent bones. If there are any defects of 1 See his paper on the Mammalia in the Encyc. Brit. vol. xv. p. 443. 2 Phoca cristata, Erxleben, Syst. Nat. p. 590; Fabric. Skrivt. af Naturh. Selsk. i. 2, p. 120, tab. 12. fig. 2; Desm. Mam. p. 241; Harlan, Fauna N. Y. p. 106. . Phoca mitrata, Cuvier, Oss. FOBS., Atlas, n. pi. 219. fig. 3. Cystophora cristata, Nilsson, Vet. Akad. Handl. 1837 ; Gray, Voy. Erebus and Terror,. M am ni. p. 4, Cat. Seals Brit. Mus. (1866) p. 40; Schreber, Fortgesetzt Wagner, vii. p. 48 ; Allen, N. Amer. Pinnipeds, pp. 462, 465, 724. Phoque a Capuchon, Buffon, Hist. Nat. Supp. vi. p. 324. |