ARCTIC ZOOLOGY. 133 



They differ from the porpoise, in the snout of the former 

 being not so blunt ; whilst that of the grampus is short, 

 blunt, and a little turned up. The remarkable difterence of 

 size too is very striking, the grampus being from twenty to 

 twenty-four feet long, and proportionally bulky. The latter 

 also is furnished only with forty teeth ; whilst the former 

 has forty-six in each jaw. 



The second variety of D. orca, sword grampus, of Avhich 

 an accurate figure is given in Plate X., Fig. 1, has the dorsal 

 fin long and bony, broad at the base, and curved like a 

 scymeter. As they advance in age, this instrimient .grows 

 longer ; so that the leader, or old one, can be distinguished 

 from his followers by the superior height of the fin. This 

 is one of the fiercest enemies of the whale, being provided 

 with such an efficient weapon of annoyance as the strong 

 dorsal fm. The sword grampus pursues also seals; and 

 the latter, in their clumsy efforts to escape upon the ice or 

 rocks, are frequently overtaken by their active adversary, 

 ,when the seals are swept from their place of retreat back 

 into the water, where they are easily vanquished. 



The sword grampus varies much in size according to 



age ; but when full grown, as the one exhibited in the 



- sketch appears to have been, it is above twenty feet long. 



The great size of the fin, from which the animal derives 



its trivial name, distinguishes it among the dolphins as 



