SHARKS. 103 



Lamnidce (Case 35) . — All the fishes of this family attain to a very [Case 35.] 

 large size and are pelagic. The Porbeagle (Oxyrhina cornubica, 

 fig. 92) occurs in the North Atlantic, frequently straying to the 



Fig. 92. 



Porbeagle (Oxyrhina cornubica). 



British coasts. It attains to a length of ten feet, and feeds chiefly 

 on fishes ; its lanceolate teeth are not adapted for cutting, but 

 rather for seizing and holding its prey, which it appears to swallow 

 whole. Carcharodon rondeletii, of which enormous jaws are ex- 

 hibited, is the most formidable of all Sharks. It is strictly pelagic, 

 and appears to occur in all tropical and subtropical seas. It is 

 said to attain to a length of 40 feet. The Fox-Shark or Thresher 



Fijy. 93. 



Thresher Shark (Alopecias vulpes). 



The figures of the teeth are those of the upper and lower jaws, of the natural 

 size, and taken from a specimen 14 feet long. 



(Alopecias vulpes, fig. 93) (exhibited in Case 35, and also in the 

 corridor leading into this Gallery) is the most common of the larger 

 kinds of Sharks which occur on the British coasts; and seems to be 



