nurceolusIn botany, any pitcher- or urn-shaped body.
nurceolusIn zoology, the external tubular casing or sheathing of a wheel-animalcule; the zoöthecium of a rotifer, corresponding to the lorica of an infusorian. It may be gelatinous and hyaline, or mixed with hard foreign particles; in rare cases, as that of Melicerta, the urceolus is not organic, but fabricated from extrinsic matter. Encyc. Brit., XXI. 5.
Chambers's Twentieth Century Dictionary
nUrceolusur-sē′ō-lus a monopetalous corolla with a contracted orifice: the external case or sheath of a rotifer