Abstract
Since MacMunn (1885), the nature and distribution of naphthaquinone pigments in sea urchins have been widely surveyed, and the main findings have been summarized in reviews by Lederer (1952), Fox (1953) and Thomson (1957). Among spinochromes and echinochromes, the most unusual one is the Spinochrome E discovered by Lederer (1952), which is insoluble in ether.Recently, the author has examined the napthaquinone pigment in the echinoid, Psammechinus miliaris (Gmel.), and has found a similar pigment to Spinochrome E together with other common spinochromes.