EN
By means of Fülleborn's direct smears and partly by decantation methods 673 children aged 7-15 years have been examined (partly 2-3 limes). The children were taken from 3 schools in Gdańsk, two of them being Municipality Schools and one located in a suburbain district without canalisation (Brętowo, near Gdańsk). In the latter school 62.62 per cent of infes tations has been stated (table No. 1). The highest percentagce was found in children aged 7-i 2 years. The difference in sex was unsignificant. The author is of the opinion that the season doesn't play any role. On the other hand, some differences depend on the social situation of the parents. The author did also comparate his work with previom in vestigations made by Kozar (1948), performed in the same city.