What is any hard protective covering of an animal, as the scales and plates of reptiles, shell of a lobster, etc. We . . . strip the lobster of his scarlet mail. Gay called?

mail — (Zoöl.) Any hard protective covering of an animal, as the scales and plates of reptiles, shell of a lobster, etc. We . . . strip the lobster of his scarlet mail. Gay. (Webster's 1913.)

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