ELECTROPHORETIC STUDY OF SOME GEOGRAPHIC ISOLATES OF ALCYONIDIUM-POLYOUM (HASSALL, 1841) (BRYOZOA, CTENOSTOMATIDA) IN THE CHANNEL AND NORTH-SEA

The comparison of proteinograms and zymograms of A Alcyonidium polyoum populations from the Channel Islands, the coasts of Channel and Wadde nsee, with some of other European populations previously studied, show s that in island localities these populations have evolved independent ly one from other and in relation to the distance from the coast. The phenograms of the Dutch population are intermediate between the <<nort hern>> and a southern pools previously discriminated in the species: t his shows, in fact, the continuity between the septentrional and merid ional populations from European continent. These populations are situa ted on the same dine, the differences being only greater on each side of the most important geographical barriers.