THE TRUE FISHES. 161 



are found on both sides of the Atlantic, and from Brazil 

 to Cape Cod. They are very ferocious. Allied is the 

 thresher shark 

 (Fig. 198). The 

 tail is fully a 

 third of the en- 

 tire length, and 

 forms a terrible 

 weapon when ^ 



SWUng about by FlG ' 'vS.-Thresher shark. 



the powerful 



fish. They attain a length of twenty feet. 



Man-Eater Shark (Lamnidce). The great Carcha- 

 rodon has been known to attack boats. Their enormous 

 mouths contain six or eight rows of serrated teeth. They 

 have a wide geographical range, are mainly pelagic, living 

 in the open sea. One species (C. gangeticus) lives in an in- 

 closed lake in the Feejee Islands, breeding above the falls. 

 It has also been found at Bagdad, three hundred and fifty 

 miles from salt water. A shark is also found in Lake 

 Nicaragua. The largest shark of this family ever caught 

 was thirty-six and a half feet long, from Australian waters. 



NOTE. In repeated observations of these and allied sharks attack- 

 ing objects on the surface and on the bottom, on the outer Florida reef, 

 in no case did they turn on their backs. In attacking a cow they ran 

 their snouts out of the water, and bit as do ordinary fishes, tearing and 

 shaking the body like a dog. One, caught after a straggle of two hours, 

 during which it towed the boat a long distance, contained among other 

 curiosities the hoofs of an ox, a mass of old rope, a tin can, and other 

 material obtained near a slaughter-house. They never attacked human 

 beings in this locality, though bathing and swimming from key to key 

 was often indulged in, where twelve and fourteen foot sharks were 

 observed only a few moments before. 



Basking Shark (Cetorhinida>}. Bone-shark, sail-fish, 

 and many other titles are applied to these sharks, that are 

 the largest of all fishes. One, captured by the schooner 



