PLAGIOSTOMES. 



355 



ference. It is harmless to man, but an enemy to whales, biting and 

 tearing these superior monsters when alive, and eating them up 



Fig. 2S8.— GREENLAND SHARK. 



when they die, gorging itself with blubber, like an Esquimaux, scoop- 

 ing hemispherical pieces, each as large as a man's head, out of the 

 whale's body, and swallowing as much as ever it can, until it has 

 so filled itself, that it has no place wherein to stow away any more ; 

 heeding no annoyance, not even the stab of a knife at dinner-time, 

 and contenting itself with a fasting diet of small fishes and crabs 

 on those days when whale-beef is not to be procured. — Mr. Afsten. 

 Tlie Saw-fishes {Pristis) (Fig. 285) are especially distinguished by 

 their very long snout, in the form of a sword-blade, armed on each 

 edge with strong bony spines, which are pointed and cutting ; this 

 terrible weapon enables its possessor fearlessly to attack the largest 

 whales. The teeth covering the jaws resemble a pavement of small 

 pebbles. The common Saw-fish attains a length of twelve or fifteen 

 feet. 



Tlie Skates (Baia) form a lars^e tribe, of which 

 the common Thornback is a familiar example. 



Fig. 289.— thouneack. 



Fishes of this family are recognisable by their body 

 being horizontally flattened, a conformation princi- 

 pally dne to the disposition of their pectoral^ fins ; 

 these are extremely broad and fleshy, and joined 



