The ultrastructure of the tegumental cytoskeleton of Fasciola hepatica has been examined following various extraction fixations. Microtubules were found throughout the tegument. They run parallel to the basal and apical tegumental borders, and have a pre-dominant basal-to-apical orientation in the central parts of the distal cytoplasm. Microtubules are also found in the cytoplasmic bridges which connect the distal and perikaryal tegumental parts.