The occurrence of Schistosoma mattheei in the south-western Transvaal.

To determine whether Schistosoma mattheei is present in the south-western Transvaal, sixty habitats were searched for the intermediate host snail, Bulinus africanus. Ten populations of this snail were located, 2 of which were infected with S. mattheei. Eggs of one of these isolates, originating from a spring in the Mooi River, were examined with an optical microscope. Scanning electron micrographs of the teguments of adult male worms and the terebratorial membranes of miracidia are described. These parasites are morphologically similar to some previously described from another habitat in the same geographical area and both populations can be regarded as typical S. mattheei.