Quercus palustris. The swamp-oak.

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1857.  His [Rev. Dumps’s] head is as obtuse and spongy as the butt end of a pin-oak rail, and yet you must submit to three hours of sermons sung once a week.—Yale Lit. Mag., xxii. 284.

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1874.  Pin-oaks, whose tiny acorns are greedily sought for by mallards and sprigtails, are unknown.—J. W. Long, ‘American Wild-Fowl Shooting,’ p. 197. (N.E.D.)

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