New components observed in association with the lacunar system of Oligacanthorhynchus tortuosa (Acanthocephala) indicate that major variations in their position and patterns may occur among the Acanthocephala. The rete network is described between the circular and longitudinal muscles as previously described for Macracanthorhynchus hirudinaceus. As yet, no connection has been observed between the rete network of anastomosing tubes and the lacunar channels. Procion dyes and India ink injected into inverted living worms outlined the flow pattern from the dorsal and ventral lacunar channels. Elements composing this system have been identified and illustrated. In a recent study Miller and Dunagan (1976) reviewed the literature concerning the lacunar system (Gefiisssystem) in Acanthocephala. They observed that Macracanthorhynchus hirudinaceus contained an elaborate organiza- tion of anastomosing channels interconnecting outer hypodermal components with the medial longitudinal channels found adjacent to the pseudocoel. In addition, these authors de- scribed a rete system which consisted of a series of connecting tubes covering the medial surface of the longitudinal muscles but separate from the lacunar system. The purpose of this study was to examine