Antigenic relationships among fishes common to the Amazon River basin

Abstract o 1. Utilizing antisera to carp and trout hemoglobins, the hemoglobins of fish common to the Amazon River basin exhibited extensive cross reactions. 2. While no fish hemoglobin precipitated with antiserum to trout 4 (anodal omponent), many hemoglobins precipitated with either antisera to trout 1 (cathodal component) or carp hemoglobins. 3. Several patterns of reactivity could be described among the polydisperse hemoglobins of various species, which were analyzed by the electrophoretic separation of the components and an assessment of the ability of individual components to react with the two types of antisera. 4. Most striking was the different reactivity noted amongst the catfishes where the hemoglobinsof air-breathing catfishes reacted more strongly with anti-trout 1 serum than with anti-carp serum, while the hemoglobins of the water-breathing catfishes behaved in reciprocal fashion.