“…Third, the prey of heliozoa, unlike that of rhizopod amoebae, adheres to the surface of the predator. Small bodies, extrusomes, which lie immediately under the plasma membrane of heliozoa have been implicated in the process of prey adhesion [Bardele, 1976;Davidson, 1976; Suzaki, Shigenaka, Watanabe, and Toyohara, 19801. This paper describes the ultrastructural aspects of prey adhesion and enclosure by Actinophrys sol. It attempts to shed some light on the subcellular events underlying the peculiar aspects of phagocytosis in this organism.…”