What is an instrument to show the time of day by means of the shadow of a gnomon, or style, on a plate. Sundial shell (Zoöl.), any shell of the genus Solarium. See Solarium called?

sundial — An instrument to show the time of day by means of the shadow of a gnomon, or style, on a plate. Sundial shell (Zoöl.), any shell of the genus Solarium. See Solarium. (Webster's 1913.)

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