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Show Orbits not very large « 496 DR. ST. G. MIVART ON T H E PINNIPEDIA. [May 19, With neither external ears nor alisphenoid canal PHOCIDA. Phocida with incisors \ CYSTOPHORINJE. A cranial pouch Cystophora. A proboscis Macrorhinus. Phocida with incisiors § STENORHYNCHINA. Nasals not prolonged backwards .... Leptonyx. Nasals prolonged backwards. Orbits very large. Teeth very small Ommatophoca. r Teeth much lobed.. .. Stenorhynchus. Not much lobed. . . . Monachus. Phocida with incisors ^ PHOCINA. Anterior nares very high. Molars little lobed Halichcerus. Anterior nares not very higb. Molars considerably lobed Phoca. CHARACTERS OF THE PINNIPEDIA GENERALLY. It may possibly be useful to enumerate the following characters which I have examined in different genera of Pinnipeds. Some of these are different in different groups, as has in part been already indicated. (1) I have found no complete septum in the auditory bulla of any genus. (2) The lip of the meatus auditorius externus projects greatly outwards in the Phocida; but it is not the median inferior part of the lip as in the Bears, but posteriorly as in the Otters. It is not prolonged outwards in the Otariida and Trichechida. (3) The paroccipital process is more or less triangular, and directed outwards, downwards, and backwards, except in Trichechus, where it forms but a small buttress against, and uniting with, the hinder side of the great mastoid. (4) The mastoid process may be considerably prominent (as in Otaria) or extremely so (as in Trichechus), or may form part of a wide-spread rounded prominence (as in the Phocida). It may form a continuous bone wall with the paroccipital process (as in Otaria), or be separated from it (as in the Phocida), or blend with it (as in Trichechus). (5) The carotid foramen is always large and conspicuous, and is placed towards, or almost at the hinder end of, the bulla, which the carotid canal traverses, towards or along its inner margin-its course being indicated externally in Otaria and Trichechus, but not at all in the Phocida. It is never concealed (as it is in the Bears) by a projecting lip of the basi-occipital. (6) The condyloid foramen is always distinct and exposed, and |