Abstract
Out of a total of 800 soil samples from public places all over Britain ova of Toxocara species were found in 24.4%. Ova from 20 samples were incubated and active embryos developed in all; these were fed to eight mice and active larvae were later recovered from the livers of six. Some children living near these parks had become infected with toxocara. Clearly more control of pollution of public places by dogs and cats is needed.