nSomatocyst(Zoöl) A cavity in the primary nectocalyx of certain Siphonophora. See Illust. under Nectocalyx.
Century Dictionary and Cyclopedia
nsomatocystThe inflated stem or body of some siphonophorans, or oceanic hydrozoans, serving as a pneumatocyst or air-sac to float or buoy these organisms, as in the case of the Portuguese man-of-war. See Calycophora, Siphonophora, and cuts under Diphyidæ and Physalia.