Fertilization, including chemotactic phenomena in the Fucaceae
Chemotaxis between gametes particularly of the Fucaceae is discussed and techniques for its detection described. Cell-free preparations of Fucus serratus and F. vesiculosus eggs have been obtained which exert a chemotactic attraction on the sperms of F. serratus , F. vesiculosus and F. spiralis , the same chemotactic mechanism among these closely related species being indicated. The chemotactic principle is easily expelled from aqueous solution by a stream of inert gas, and may be recovered in a cooled receiver; it seems therefore to be a simple compound. Various arylacetic acids have a marked effect on the Fucus sperms studied but this effect is distinct from true chemotaxis and is not related to the plant hormone or herbicide activities of the responsible acids.