TIGERS OF THE DEEP 



snapped its jaws within a few inches of the corpse of a 

 negro, suspended from a yard-arm twenty feet above the 

 sea's surface. 



Many authorities say that because a shark's mouth is 

 placed in the lower part of its head, it becomes necessary 

 for it to turn over on its back before it can seize any 

 swimmer on the surface ; and that natives, knowing this 

 habit of the shark, take advantage of it and plunge their 

 knives into the killers as they turn. But other authorities 

 claim that the shark is too shrewd to make itself vulner- 

 able by any such action, and point out that it continually 

 devours creatures of the sea-beds while remaining in a 

 normal position, with its mouth pressed downward. The 

 truth may be a compromise between the two view- 

 points. Sharks certainly do turn over as they attack — but 

 not always. 



The white shark — known the world over as the man- 

 eater — is white below and brown on its upper parts. It is 

 almost a stranger to Britain's shores, but stray specimens 

 sometimes appear, particularly in hot summers. This is 

 one of the largest sharks that range the oceans, and in 

 some seas they are so numerous that they are the terror 

 of natives and sailors. One specimen, whose jaws are still 

 preserved, measured no less than thirty-seven feet in 

 length. Specimens twenty feet long are fairly common. 



This tiger of the deep is rivalled, in its destructive 

 habits, by the blue shark — another monster that has 

 earned the name of man-eater. It is slaty-blue on its 

 upper, and white on its under parts. Exceedingly destruc- 

 tive to shoals of food-fishes, it will pursue them even into 

 fishermen's nets. 



The thresher shark, another variety, ranges from 

 twelve to fifteen feet in length, and is known by its 

 elongated upper tail lobe. This it uses to stun and kill 

 hosts of smaller fish — numbers of threshers suddenly 

 rushing into a school of them and herding their victims 

 into a mulling panic-stricken circle as they furiously flail 



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