What is (a) The horny inferior surface of the lingua of certain insects. (b) One of the small, spiniform scales found on the front edge of the dorsal and caudal fins of many ganoid fishes called?

fulcrum — (Zoöl.) (a) The horny inferior surface of the lingua of certain insects. (b) One of the small, spiniform scales found on the front edge of the dorsal and caudal fins of many ganoid fishes. (Webster's 1913.)

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