332 REPORT OF NATIONAL MUSEUM, 1S84. 



is slightly mottled ou the belly." In oar specimen the hairs of the back 

 and hind flippers appear light at the tip, as if faded by age; but are 

 dark sei)ia color or nearly black, excei)t at the extremity. On the 

 under parts and on the sides of the body, neck, and head the dark hairs 

 are interspersed by others which are white except at the tip. The lips 

 are bordered with white. On the upper lips the hair above the white 

 fringe is darker than that of the surrounding surfaces. The palms are 

 not bare, as stated by Gosse, but are equally as well clothed as the upper 

 surfaces of the flippers. It is probable that the specimen described by 

 Hill had worn the hair from the iinder surfaces of the flippers by con- 

 tact with the dry surfaces of the inclosure in which it was confined. 



The skull. — The skull before us presents no characters which would 

 warrant a separation of the species generically from M. albiventer, the 

 type of the genus Monachus. The specimen agrees perfectly with the 

 diagnosis of the genus given by Gray in the Hand-list of Seals, &c. 

 (1874, p. 11). 



In general form the skull is depressed and elongated, the breadth 

 being exactly three-fifths the length. Compared with Plioca vituUjia, 

 the muzzle is much less tapering; viewed from above, its sides are ap- 

 proximately parallel. The intermaxillaries meet the nasals and extend 

 along their sides for about half an inch. Nasals narrow, somewhat less 

 than one-fourth the length of the skull, and emarginate anteriorly. 



The interorbital region is broad, with parallel sides, much as in Erig- 

 nathns. The frontals are in contact with the temporals posteriorly, and 

 to a greater extent on the left than on the right side. The contour of 

 the parietals is rudely square, the posterior margin being emarginate. 

 In the specimen under consideration the sagittal and occipitoparietal 

 sutures are still open. The sagittal and lambdoidal crests are rudiment- 

 ary. 



The malar rests upon the maxillary anteriorly. A line drawn from 

 the outer edge of the canine parallel to the median line cuts the an- 

 terior end of the malar. The maxillary supports the malar internally 

 for more than half the length of the latter. The articulation of the 

 malar with the squamosal presents no peculiarities. 



The " palate" is strongly contracted at the juncture of the anterior 

 and middle thirds, and acutely emarginate behind. The posterior pala- 

 tine foramina lie wholly in the maxillary. 



The posterior nares is small ; its margin forms an equilateral triangle. 

 The narial septum is very incomplete. 



The auditory bullae are pyriform in outline and depressed, the upper 

 surface traversed by a distinct groove. The lateral extension of the 

 bulla forming the wall of the meatus anditorius is incomplete in front. 

 The anterior margin of the bulla is deeply concave. The bulloe diverge 

 strongly posteriorly. 



The foramen magnum is broader than high. The paroccipitals are 

 well developed, short, and thick. 



