| helisoma duryi: its present range of distribution and implications with schistosomiasis snails in egypt. | the range of distribution of helisoma duryi, a potential competitor to schistosomiasis snail vectors in egypt, was determined in the south of nile delta. results show that h. duryi was found in the river nile, geziret el kerateyeen banks, damietta and rosetta branches, tawfiky and menoufy canals and their branches and bassoussiya, bahadiya and sheshaa canals and their branches. helisoma was found in all categories of canals and drains co-existing in various degrees with other snail species inclu ... | 1993 | 8482866 |