Laboratory colonies of Anopheles gambiae, An. arabiensis, An. merus, An. quadriannulatus and Aedes aegypti formosus were artificially fed on blood containing microfilariae of Wuchereria bancrofti. The anopheline colonies all supported parasite development to the infective stage, with An. quadriannulatus being the most heavily infected. The parasite did not develop at all in the Ae. aegypti formosus colony.