Published online by Cambridge University Press: 31 May 2012
This paper is a report on the discovery of distinct morphological differences between DDT-resistant and non-DDT-resistant strains of the house fly, Musca domestica L. Since DDT-resistant house flies were first reported in Italy in 1945-46, such differences have been sought by a number of workers (e.g. Wiesmann, 1947; D'Alessandro et al., 1949; March and Lewallen, 1950; Anon., 1950). Various slight differences have been detected but none of a magnitude comparable to those described in this paper has so far been reported.