102 ME. F. E. BEDDAKD ON THE 



The vertex of the skull is situated just behind the nasal bones. 



The nasal hones are not unlike those of other Mystacoceti in their general form. It 

 will be observed from the drawing (PI. VIII. fig. 1) that they are distinctly asym- 

 metrical when seen from above ; the right bones are larger than the left. This 

 drawing, it should be explained, is a copy of the skull of the younger individual. 



The maxiUw{V\. VIII. fig. 1, PI. IX. fig. 1, Mx.) are, as usual in these whales, bones 

 of a bent form ; the posterior half meets the anterior half at an obtuse angle. The 

 former is much shorter than the latter, the proportions being as 1 : 2. The actual 

 lengths, as measured, are respectively 16 and 33 inches. The form of this bone as 

 regards tlie proportions of its two halves is like those of the Right Whales and 

 contrasts with those of the Rorquals. In the latter the descending bar of the maxilla, 

 though it reaches below the orbit in BalcBnoptera, as it does in Neohalcena, is distinctly 

 shorter, the anterior portion being thus relatively much longer in that genus of whales. 

 Another character of this bone shows in Neohalcena a close likeness to what obtains in 

 the geniis Bahena. There is posteriorly a ridge near to the posterior boundary which 

 curves round, but is of comparatively slight extent, both in Neohalcena and Balcena. 

 In Balceno])tera, on the contrary, we find that this ridge is very much more marked, 

 and that it extends further, curving backwards in the direction of the occipital region 

 of the skull, and, as it were, sheltering the frontal bone behind. The maxillae do not 

 reach the end of the jaw. 



The inner angle of each maxilla is prevented by the premaxillge from coming into 

 contact with the nasals ; it extends back, as already mentioned, for a little way beyond 

 the outer portion of the bone, that portion which extends backward being of about 

 the same diameter as the adjacent premaxillary. In Balcena there is the same failure 

 of the maxillae to articulate with the nasals ; but the forwardly running portion of the 

 bone is hardly difi'erentiated. The Rorquals, on the other hand, show an entirely 

 different arrangement of these parts. The internal angle of the maxilla is prolonged 

 into a long and narrow process, which extends for a long way backwards and articulates 

 directly with the nasals. There is completed in some of these whales a condition 

 which is only just commencing in the genus Neohalmna. 



The frontal (PI. VIII. fig. 1, PI. IX. fig. 1, Fr) bone of Neohalmna is, on the other 

 hand, decidedly more like that of Balcenoptera than of Balcena. If the skulls of the 

 two latter genera be compared with each other, it will be noted that they differ 

 markedly in the width of the frontal bones. In the Rorquals these bones are very 

 broad, and thus get an appearance of being much shorter than those of Balcena, which 

 are narrow, and, indeed, hardly exceed in width the descending part of the maxilla. 

 Furthermore, their backward inclination in the Right Whale is much more marked 

 than in the Rorqual. As will be seen from the drawings exhibited (Pis. VIIL & IX. 

 fig. 1), the conditions which are to be met Avith in this region of the skull of Neohalmna 

 are quite like those of the Rorqual. The descending part of the frontal, where it 



