Measurements of diatom adhesion and their relationship with movement

Abstract

Adhesive and tractive forces of diatoms have been measured by the bending of a glass fibre. The results show that motility depends on attachment to the substrate. Movement on girdle bands occurs when the raphe acts against lumps of trail substance. Resistance to shear stress in laminar flow through a capillary tube is found to be particularly high in large epipsammic spp., e.g. Amphora ovalis, and is related to strong adhesion. The mechanism of movement is discussed in relation to the physical properties of the raphe and trail.