EXPERIMENTAL TRANSMISSION OF THE NEMATODE ECHINOMERMELLA-MATSI TO THESEA-URCHIN STRONGYLOCENTROTUS-DROEBACHIENSIS IN THE LABORATORY

Three experiments were conducted to investigate the possibility of mai ntaining the Echinomermella matsi-Strongylocentrotus droebachiensis sy stem in the laboratory. The experiments were performed by injecting E. matsi larvae taken directly from gravid female nematodes into the mou ths of sea urchins. In all experiments, this treatment resulted in a h igher infection in treated animals than in unmanipulated controls. The successful establishment of larvae indicates that E. matsi has a mono xenous life cycle. The growth of larvae in experimentally infected hos ts was slow, indicating that the generation time of the parasite is of the same magnitude as the life expectancy of the host, 1-2 yr. This s low growth rate suggests that considerable resources will be needed to maintain the system in the laboratory.