ON THE GREENLAND RIGHT-WHALE. 



91 



being the cranium of a rorqual, so the direction of the orbital processes of the superior maxillaries 

 and the frontals, as well as the greatly advanced 

 situation of the squamous portion of the occipital, 

 are sufficient to show that the right -whale to 

 which this fragment belonged was more closely 

 related to the Greenland whale than to the Cape 

 whale ; but at the same time we may find suffi- 

 cient reason in the narrowness of the squamous 

 portion of the occipital, and in the greater 

 breadth and smaller length of its lateral parts, to 

 suppose that this fragment should be referred to 

 a particular species belonging to the North whale 

 group. 



On the basal surface of the cranium (Plate 

 IV, fig. 2) the superior maxillaries are seen still 

 partially retaining their superiority in the for- 

 mation of the bony palate. The limits between 

 their lateral portions {processus orbitales) and the middle portion behind appear in the form of a 

 very deep fissure in their palatine surface. This forms the entrance into a deep cavity in 

 the interior of the bones, and the fissure is prolonged anteriorly in the form of a series 

 of foramina for vessels and nerves. Numerous similar foramina are found close around the 

 fissure itself. The middle portion of the palatine surface of either of the superior maxillaries is 

 again divided behind into two narrow prolongations, of which the exterior is the longer. The 

 cleft between them is occupied by the anterior end of the palatine bones. In the full-grown 

 Greenland whale this end of the palatine bones is pointed, and these bones [p) are, generally 

 speaking, narrow. They separate from each other behind in an acute angle, in which a small 

 part only of the nasal septum formed by the vertical plate of the vomer is visible. To the 

 posterior edge of the palatines, which is turned very much in an outward du-ection, the palatine 

 plate of the pterygoid bones (a) is as usual attached, on the free edge {h) of which a hook, 

 properly so called {hamulus pterygoideiis), can scarcely be distinguished (as is the case with the 

 rorquals). Of the pterygoids we may, besides the above, see on the lower surface of the cranium, 

 not only the narrow prolongation before mentioned, serving as a support to the part of the 

 parietal which enters into the formation of the tube of the optic nerve, but also a small part of 

 their middle portion deeply wedged in between the rest of the bones. 



The palate, and with it the cavity of the mouth, is in the full-grown Greenland whale so much 

 prolonged backwards that its posterior edge, formed by the pterygoids, nearest to the middle line, 

 will be found to be at the same time the posterior edge of the lower surface of the cranium 

 Itself. The bones corresponding to the floor of the skull and the organs of hearing have 

 been removed so much upwards, or have become so extensively covered by the palatine bones, 

 or have, at any rate, become so small, comparatively speaking, that they are either quite 

 invisible, or subordinate to the bony portions belonging to the lateral prolongations of the 

 palate and the occiput. In no other part shall we find the cranium of the newborn animal so 

 different from that of the full-grown one as here ; and as a fm-ther illustration of this point, we 

 have given a woodcut of this region in our newborn Greenland whale, to be compared with the 



