The poisonous puffer fish, which inflates itself into a small balloon when caught, lives in most of the world's oceans. But only in Japan, where it is called fugu, has it become a national tradition. There, though its poison kills 200 victims per year, its flesh sends gourmets into philosophical ecstasies. They get a particular kick from knowing they are playing a kind of gustatory Russian roulette.
The fugu has drawn additional attention by its long-defiant challenge to the chemists' skill. Its poison, tetrodotoxin, has proved almost impossible to isolate or identify....