||Sphæ*rid"i*um (?), n.; pl. Sphæridia (#). [NL., fr. Gr. &?;&?;&?; a sphere.] (Zoöl.) A peculiar sense organ found upon the exterior of most kinds of sea urchins, and consisting of an oval or sherical head surmounting a short pedicel. It is generally supposed to be an olfactory organ.

||Sphæ*rid"i*um (?), n.; pl. Sphæridia (#). [NL., fr. Gr. &?;&?;&?; a sphere.] (Zoöl.) A peculiar sense organ found upon the exterior of most kinds of sea urchins, and consisting of an oval or sherical head surmounting a short pedicel. It is generally supposed to be an olfactory organ.