ABSTRACT
A quantitative biological test was routinely used to determine the GSS activity of the radial nerve cord throughout the year, as well as to investigate the possible occurrence of GSS in selected “hemal” organs (i.e. axial organ and gastric hemal tufts). The test used was that of Bouland and Jangoux (1983). It facilitates the establishment of a “spawning index” for pieces of mature ovaries in the presence of crude extracts of tissues or organs that are supposed to have GSS activity. The results indicate that the radial nerve cord has GSS activity, whatever the period of the year. However, this activity varies, being lower during the summer months. It regularly increases during ovarian growth, reaching a maximum at the spawning period. Preliminary assays with hemal organs and coelomic fluid indicate that the GSS is conveyed either through the hemal system itself or through hemal-associated tissues. They show, moreover, that the GSS seems to be continuously translocated throughout the year, whatever its concentration in the nerve cord.
