DIFFERENCES IN THE EGG MORPHOLOGY AND CERTAIN BIOLOGICAL CHARACTERISTICS OF SOME AFRICAN AND MIDDLE EASTERN SCHISTOSOMES, GENUS SCHISTOSOMA, WITH TERMINAL-SPINED EGGS.

There is some confusion regarding the differentiation of African and Middle Eastern schistosomes with terminal-spined eggs. In an attempt to clarify the situation, the author has separated the members of the genus Schistosoma that have terminal-spined eggs into three broad groups and five species on the basis of egg morphology and certain biological characteristics.THE GROUPS ARE: the haematobium group, with one species (S. haematobium); the bovis group, with three species (S. bovis, S. mattheei and S. leiperi); and the intercalatum group, with one species (S. intercalatum). Further species separation is not thought to be justified yet, and reasons are given for considering S. capense and S. curassoni as synonymous with S. haematobium and S. mattheei respectively.