Abstract: | The univalency concept of the mechanism responsible for the failure of incomplete antibodies to produce direct agglutination of appropriate untreated red cells has been investigated. Artificially produced univalent (hybrid) 7S antibodies were found to differ in serologic behaviour from incomplete anti-Rh antibodies of the same molecular size. The data suggest that the so-called `univalent' anti-Rh antibody molecule is bivalent. |