A rattle snake.

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1827.  The snakes of the prairies are harmless, unless it be now and then an angered rattler, and he always gives you notice with his tail, afore he works his mischief with his fangs.—J. F. Cooper, ‘The Prairie,’ i. 249. (N.E.D.)

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1878.  Another told of stirring up an immense rattler while he was hoeing corn.—J. H. Beadle, ‘Western Wilds,’ p. 133.

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1910.  In the North Carolina mountains, where rattlers are as plentiful as long-legged natives, the man considers a flask of “mountain dew” a necessary companion at all times, even if he is not a habitual drinker.—N.Y. Evening Post, Aug. 1.

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