part of part of in taxon Acoelomorpha Bilateria Eumetazoa multi-tissue structure coelom Wikipedia:Coelom coelomic cavity haemocoelom EHDAA2:0004731 enterocoelom EHDAA2 distingsuishes between the lumen, the lining, and the 'coelomic cavity', which despire it's name, is not a space - it is the aggregate of space plus lining. UBERON:0011997 coelomic schizocoelom The aggregate of the coelemic cavity lumen plus the membranes that line the lumen. coelem ZFA:0001438