562 DR. J. E. GRAY ON THE BOTTLENOSED WHALES. [Nov. 12, 



specimens, all obtained at the same time from the same school of 

 these Dolphins from the Firth of Forth. 



In the skull of the old male the sheath of the opening is nearly 

 flat below and on the sides, the lateral ridges being almost on the edge. 



In the skull of the full-grown female the sheath of the hinder 

 nasal opening is nearly similar to that of the male, but the sides are 

 more convex and swollen. 



The third skull of a full-grown animal, the sex of which was not 

 marked, is very like the skull in the British Museum that Colonel 

 Montagu described as Delphinus truncatus, and it has, like the latter, 

 all the teeth much worn down and truncated. They both differ 

 from the skull of the adult male and of the full-grown female in the 

 sheath of the hinder nasal aperture being rather narrower, more 

 deeply impressed in the centre, and in the lateral keel being more 

 within the margin, making the side of the sheath more convex and 

 rounded. 



Being very desirous of obtaining information bearing on the geo- 

 graphical distribution of Cetacea, and hearing that Mr. Moore, of 

 the Liverpool Museum, had recently obtained the skull of a Bottle- 

 nosed M^hale (Tursio) from the west coast of Africa, I requested 

 him to send it to the British Museum for examination and com- 

 parison. It is intermediate, in some respects, between the skulls of 

 the Tursio truncatus, of the English coast, and T. metis, the locality 

 of which is unknown. It has the large teeth and long teeth-line of 

 the T. truncatus ; indeed the teeth-line is above half an inch longer 

 than in that species ; but the beak of the skull is rather slender : in 

 this latter character it is more like T. metis ; but that species has 

 a rather shorter teeth-line even than T. truncatus. 



If it were not that I have lately observed that Dolphins that differ 

 very little from each other in the form and proportion of their skulls 

 have very different external characters, I should be inclined to think 

 that T. truncatus, T. metis, and the specimen from West Africa 

 were all of one species, varying a little in the form of the skull ; but 

 we must leave this question for further examination, more especially 

 as different authors have described the living Tursio that came 

 under their examination as being very differently coloured externally, 

 and only record that a species of Tursio is found on the west coast 

 of Africa, as well as in the North Sea, the Bay of Biscay, the Medi- 

 terranean, and the Red Sea. 



The following are the measurements of the West-African skull : — 



inches. 



Length entire 22^ 



of beak 1 .3 



of teeth-line. . II 



Width of brain-case lOg 



of beak at notch b-^ 



of beak between tenth and eleventh tooth . . 3^2 



The skull was presented to the Liverpool Museum by Mr. J. Lewis 

 Ingram, of the Temple, who obtained it at the Gambia. 



