| OCR Text |
Show 492 DR. ST. G. MIVART ON THE PINNIPEDIA. [May 19, ossification in the basi- and exoccipitals they are very small. The palate is much prolonged behind the last molars, and its hinder margin is concave. The palatine foramina are situated in its hinder half. There are both a subangular and an angular process to the ascending ramus of the mandible, but both these processes are very small. The skull agrees generally with that of Phoca, in points not here mentioned. Dentition : - I . \, C. \, P. \, M . *=30. Only the last upper molar has generally two roots. The roots of the molars are long and swollen; their crowns are small and rather plaited than lobed. Macrorhinus1.-This genus contains two species; one ranging the South Pacific, Indian, and Antarctic Oceans, and the other inhabiting the coasts of Mexico and Southern California. Here the claws of the manus are small, and those of the pes are quite rudimentary or altogether absent. The nose of the male has a short, dilatable proboscis. The first and fifth toes exceed the others and have prolonged cutaneous lobes. There are 15 dorsal, 5 lumbar, 3 or 4 sacral, and 9-11 caudal vertebrae. The skull has rather small nasals, which are separate and are not attained by the premaxillae. The anterior nares are wide, especially dorsally, as in the last-described genus. The skull of this genus differs from all those of the genera yet noticed in that the posterior half of the petrosal and the condyloid foramina may look directly backwards. There is hardly any paroccipital process, and the mastoid process is only developed in old males. The palate may have a deeply concave hinder margin, or, being generally concave, may have a prominent process in its middle. The crista galli is large, but the cerebellar fossa of the petrosal is small. There are small venous channels in the supraoccipital which open on the dorsal margin of the foramen magnum. There is a deep groove behind the postglenoid process, in which is a small glenoid foramen. There is a moderate suborbital foramen, writh no deep fossa beneath it. I have observed no defects of ossification in the occipital or between the palatine and pterygoid and the sphenoid. The foramen ovale is thrown outside the vertical wall formed by the pterygoid, which passes backwards to join the petrosal. There is a minute subangular process, pushed up very closely to the angular process, which itself is but little below the condyle. Dentition:-I. \, C. \, P. i M . J = 30. 1 1 4 1 1 Phoca leonina, Linn. Syst. Nat. i. (1765) p. 38. Phoca elcphantina, Molina, Sagg. sul 8tor. nat, del Chili (1782), p. 280. Phoca proboscidea, Peron, Voy. aux Terr. Austr. ii. (1817) p. 34, pi. xxxii. Cystophora proboscidea, Nilsson, Vet. Akad. Handl. (1837); Schreber's Fortgesetzt Wagner, vii. p. 42. Morunya elejjhantina, Gray, Cat. Seals Brit. Mus. (1866) p. 38. Macrorhimis leoninus, Allen, N. Amer. Pinnipeds, pp. 463, 466, 743. See also Flower, P. Z. S. 1881, p. 145, an important memoir. Grand Phoque a museau ride, Buffon, Supp. vi. p. 316. |
