New aspects of pheromone-triggered spermatozoid release inLaminaria digitata (Phaeophyta)

Summary Explosive spermatozoid release inLaminaria digitata is triggered by a pheromone secreted by female gametes. Dependence of the pheromone action on extracellular cations was investigated in defined test media using a pure pheromone preparation. The experimental results indicate successive processes in the sensory system and are summarized in a hypothesis on the release mechanism. The polysaccharide composition of the antheridial cell wall and the mucilage surrounding the spermatozoid was identified by cytochemical methods.