Abstract
A biochemical polymorphism of coelomic hemerythrin has been found in the sipunculid Golfingia gouldii; the electrophoretically "fast" and "slow" coelomic hemerythrins differ in their oxygen equilibria and by a single peptide in tryptic and chymotryptic "fingerprints." All individuals of this sipunculid have the same vascular hemerythrin, which is electrophoretically different from any of the coelomic hemerythrins. Vascular and coelomic hemerythrins of another sipunculid, Dendrostomum cymodoceae, have quite different "fingerprints." Thus, on the basis of two separate types of evidence the tissue-specific hemerythrins appear to have a distinct genetic basis. The embryological and phylogenetic implications are discussed.