Samples of 25 African populations of Aedes aegypti (L.) were examined for variations in scale-colour pattern of palps, halteres, abdominal tergites and metatarsi and in larval body colour. A colour index based on these characters showed domestic populations to be paler than populations found in forests. Classification of phenotypic and genotypic variations in the amount of pale scaling on palps, halteres and, especially, tergites revealed statistically significant differences between some of the populations. Although it was impossible to identify individual mosquitoes, population samples could be identified according to subspecific designations as A. a. formosus (Wlk.) and A. a. aegypti.