The case history of four patients is presented. The first patient exhibited normal immunologic reactions to large artificial intradermal challenge with jellyfish venom and, later, multiple small natural stings. The second patient, presumably envenomated by a jellyfish, had four recurrent cutaneous eruptions in a linear configuration at the same anatomic site. Because her primary coelenterate contact occurred at a time when she was receiving systemic corticosteroids, it is assumed that the eruption due to the initial sting was delayed. The third and fourth patients exhibited recurrent eruptions after solitary envenomations by different coelenterates. These case histories demonstrate that multiple recurrent eruptions may follow solitary envenomations by different subphyla of coelenterates, that the initial emption induced by the sting may be delayed by the administration of high doses of systemic corticosteroids, and that an immunologic reaction in both the B and T cell systems can follow jellyfish envenomation.