The toxins of Lutjanus bohar Forskal, a red snapper, were investigated as an example of the Ciguatera-type fish poisoning found in the Central Pacific. Only the domestic cat and the mongoose (Herpestes javanicus) when fed toxic fish produced symptoms paralleling those of man; mongooses were used as test animals. Their symptoms included the loss of reflexes, a progressive loss of coordination, and death. The toxin was found undiminished after 6 months frozen storage and after dehydration at 102-108[degree]C for 24 hours. The toxin was insoluble in distilled water but soluble in 90% ethanol. Organic solvents, including diethyl ether, petrol ether and chloroform, would detoxify the poison. When the alcoholic extract was re-extracted with organic solvents under a N2 atmosphere (about 3% O2) only partial detoxification occurred, and the toxin was in the chloroform or diethyl ether fractions. The reliability of the previously used test, in which mice were given an intraperitoneal injection of the centrifuged aqueous extract of macerated fish flesh, was investigated; a L. bohar known to be lethal from feeding tests caused only mild reactions when tested by this technique. It was established that the reaction in mice was caused by the suspended matter in the extract and that the toxin was not carried by the water in solution.