CAPE OF GOOD HOPE. 



157 



The villages between Simons Bay and Wynberg have fences 

 made of various bones of whales. A whale fishery was formerly 

 carried on here, but no longer pays. An extremely interesting 

 and very rare whale is occasionally procured at the Cape. It is 

 a Ziphioid, Mesoplodon layardii. The Ziphioids are a group of 

 the toothed whales and allied to the sperm whale. They have 

 the bones of the face and upper jaw drawn out and compressed 

 into a long beak -like snout which is composed of solid bone, 

 hard and compact like ivory. The upper jaw is devoid of teeth, 

 having lost them in the process of evolution, and the lower jaw, 

 which is lengthened and pointed to correspond with the upper, 

 retains but a single pair of teeth. 



In the species in question, Mesoplodon layardii, these two 

 teeth in the adult animal become lengthened by continuous 

 growth of the fangs into long curved tusks. These arch over the 

 upper jaw or beak, and crossing one another above it at their 

 tips, form a ring round it and lock the lower jaw, so that the 

 animal can only open its mouth for a very small distance 



1 Skull of Mesoplodon layardii. 2 Lower jaw ; a small cap of dentine on the tooth. 3 Top of lower 

 jaw seen from the front, showing the ring formed by the teeth. Copied from the British 

 Museum Catalogue of Seals and Whales. 



indeed. The tusks are seen always to be worn away in front 

 by the grating of the confined upper jaw against them. How 



