hydrotheca 螅鞘; 螅鞘
Hy·dro·the·ca n.; pl. L. Hydrothecæ E. Hydrothecas Zool. One of the calicles which, in some Hydroidea (Thecaphora), protect the hydrants. See Illust. of Hydroidea, and Campanularian. ◄ ►