“…Considering their involvement in regulating the life-cycle of the worm parasites various aspects of the biology and ecology of these freshwater gastropod snails were studied by Seshaiya (1927), Noland and Carriker (1946), Kendall (1953), McCraw (1970), Berrie (1965), Burla and Speich (1971). Van der Steen et al(1973), Hunter (1975) , Raut and Misra (1993), and Misra and Raut (1993) with a view to developing methods for control. Although additional information on ecology of lymnaeids is available (Jong-Brink 1990, Moens 1991 an effective control device for these snail intermediate hosts has not been found.…”