The varied denticles shown in these samples are from 7 species of sharks: (1) Tiger 

 shark ( Galeocerdo cuvieri ) ; ( 2 ) Basking shark ( Cetorhinus maximus ) ; ( 3 ) Cat shark 

 ( Scyliorhinus boa ) ; ( 4 ) Thresher shark ( Alopias vulpinus ) ; ( 5 ) Brown shark ( Car- 

 charhinus milberti); (6) Smooth dogfish {Mustelus canis); (7) Sand, or Sand Tiger, 

 shark (Carcharas taurus). Note: in these and other species, the denticle pattern may 

 vary throughout the shark's body, so that these denticles are not necessarily a positive 

 means of identification. U.S. Bureau of Fisheries 



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