Palytoxin (1) is an extremely poisonous substance associated with marine coelenterates (zoanthids) of the genus Palythoa(7). Its intravenous lethality (LD50), which ranges from 0.025 µg/kg in the rabbit to 0.45 µg/kg in the mouse (2), is exceeded only by certain proteins and polypeptides (3). The toxicity of Palythoa, was probably noticed for the first time by the Hawaiians who used exudates of a rare, but very toxic species, P. toxica(4), to poison spear tips for warfare. Investigators at the University of Hawaii were led to P. toxicawhen they followed up the lead provided by the entry limu-make-o-Hana(the deadly seaweed of Hana) in the Hawaiian-English Dictionary (5). Japanese researchers, on the other hand, were led to P. tuberculosawhen they traced the dietary origin of a water-soluble toxin that had been found in the digestive tract of some toxic filefish, Alutera scripta(6,7).