IN Nature of March 12, p. 749, Drs. L. R. Cox and W. J. Rees reviewed a paper by the Japanese authors Kawaguti and Baba on a bivalved gastropod they had described under the generic name Tamanovalva. I should like to put on record a further occurrence of this remarkable group of molluscs. A single left valve (now in the Stanford University Collection, California) of what is probably a new species, with the characteristic spiral nucleus and central adductor muscle scar, was collected on Espritu Santo Island, near La Paz, Gulf of California, in beach drift, on November 1, 1959.