Abstract
Although the biological control of medically important snails has been suggested from time to time during the past quarter of a century (Nagano, 1927; Bequaert, 1928; Mozely, 1939, 1951; McMullen, 1952), the subject has, as yet, received but little serious consideration. Upon the initiation of our studies (Chernin, Michelson & Augustine, 1956a,b) the literature was searched for references to predators, parasites and diseases of molluscs which might furnish leads for experimental investigation.