158 A NATUliALIST ON THE " CHALLENGER." 



the animal manages to feed itself under these conditions is a 

 mystery. 



It is remarkable that the main mass of each tusk is made up 

 of what appears as an abnormal growth of the fang.* The 

 actual conical tooth, that is the original small cap of dentine of 

 the tooth of the young animal, which corresponds to the part of 

 the tooth showing above the gum in other whales, does not 

 increase at all in size, but is carried up by the growth of the 

 fangs, and remains at the tips of the tusks as a sort of wart-like 

 rudimentary excrescence. 



Specimens of Mesoplodon layardii are excessively rare, and 

 I sought diligently for such during the whole of my stay at the 

 Cape, and was rewarded by procuring parts of two skulls. One of 

 these, a skull without the lower jaw, I found near Mr. McKellar's, 

 at Cape Point. The skull was exposed on the beach, being stuck 

 up with its beak thrust into the sand to be used as a rifle 



target. 



The animal, as Mr. McKellar told me, had come on shore 

 about eight years before. It yielded oil of a very superior 

 quality, which sold for more than twice the price of ordinary 

 whale oil. It was about 10 feet in length, and was, as far 

 as he remembered, coloured black on the back and white on the 

 belly, with a conspicuous line of demarcation of the colours on 

 the side. The beast had the usual tusks. 



The other specimen consisted of the snout and lower jaw, 

 with the tusks of another example of the species. It was given 

 me by Mr. A. M. Black, of Simons Town. The animal came on 

 shore at Walwick Bay in 1869. It yielded 80 gallons of oil, 

 and was from 16 to 18 feet in length. It is remarkable that 

 these whales seem never to be met with or caught at sea. They 

 always are procured by their running on shore. The Ziphioids 

 are especially interesting, because many species were abundant 



* Prof. Owen, with the single original specimen only before him, 

 considered that the tusks had acquired " an abnormal direction and state 

 of growth "in that particular specimen. " Palseontographical Soc.,"Vol. 

 XXIII 1869 p 26. Prof. Flower, though knowing of a second specimen, 

 still seems do'ubtful. "Trans. Zool. Soc," Vol. VIII, 1874, p. 211. Now 

 that more specimens are known, there can be no longer doubt as to the 

 normal occurrence of the condition described. 



