The Sex Lives of Cannibals vocabulary

large lamniform sharks of the family Alopiidae found in all temperate and tropical oceans of the world; the family contains four species, all within the genus Alopias.

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Named for their exceptionally long, thresher-like heterocercal tail or caudal fins (which can be as long as the total body length), thresher sharks are active predators; the tail is used as a weapon to stun prey. The thresher shark has a short head and a cone-shaped nose. The mouth is generally small, and the teeth range in size from small to large.

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Pelagic schooling fish (such as bluefish, juvenile tuna, and mackerel), squid and cuttlefish are the primary food items of the thresher sharks. They are known to follow large schools of fish into shallow waters. Crustaceans and occasionally seabirds are also taken.

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Threshers have a low fecundity, like all large sharks, and are highly vulnerable to overfishing. Besides being hunted for their meat, threshers are also hunted for their liver oil, skin (for leather), and their fins, for use in shark-fin soup.

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This gentleman is famous for his tail which he uses for a ferule in thrashing his foes. He mounts the Folio whale's back, and as he swims, he works his passage by flogging him; as some schoolmasters get along in the world by a similar process.