Opening Session.- Homage to Ren? Lontie.- Hemerythrins.- Structure, function and oxidation levels of hemerythrin.- Structure and Function of Invertebrate Hemoglobins.- The dissociation of the extracellular hemoglobin of Lumbricus terrestris: A model of its subunit structure.- Subunit structure of earthworm erythrocruorin.- Characterization of trimeric hemoglobin component from the earthworm, Lumbricus terrestris.- The structure of the extracellular hemoglobin of annelids.- Ophelia bicornis erythrocruorin. Some peculiar features.- Structure of annelid hemoglobins small angle X-ray studies.- Structural analogies in annelid erythrocruorins.- Role of SH-groups and S-S bridges in the main subunit (1/12 molecule) of Spirographis spallanzanii chlorocruorin.- Subunit structure and amino acid sequence of the extracellular hemoglobin from the polychaete Tylorrhynchus heterochaetus.- A preliminary study of the hemoglobin of Arenicola marina.- Oxygen equilibria of whole molecules, isolated subunits and the subunit trimer of hemoglobin from Lumbricus terrestris.- The amino acid sequence of a structural unit isolated from the high molecular weight globin chains of Artemia sp..- Quaternary structure and modulation of function in earthworm erythrocruorin.- Calcium dependent allosteric modulation and assembly of the giant hemoglobin from the earthworm, Eisenia foetida.- Quaternary structure of erythrocruorin from the aquatic snail Helisoma trivolvis.- Immunochemical properties of molluscan hemoglobins.- Studies of the heme environment in molluscan hemoglobins by EPR.- The cooperative dimeric hemoglobin from the mollusc Scapharca inaequivalvis: structural and functional characterization.- The low resolution structures of the cooperative hemoglobins from the blood clam Scapharca inaequivalvis.- Structure and function of the dimeric and tetrameric hemoglobins from the bivalve mollusc, Anadara broughtonii.- Cosolvent effects on hemoproteins oxygen uptake and equilibria.- Hemoglobin flc-