Nectocalyx

||Nec`to*ca"lyx (?), n.; pl. Nectocalyces (#). [NL., fr. Gr. ? swimming + ? a calyx.] (Zoöl.) (a) The swimming bell or umbrella of a jellyfish of medusa. (b) One of the zooids of certain Siphonophora, having somewhat the form, and the essential structure, of the bell of a jellyfish, and acting as a swimming organ.