The majority of female Toxorhynchites R. rutilus oviposited only in black containers, but about 21% of the females laid some eggs in a white container even in the presence of a black one and 26% used a white container only if a black one was not available. The choice of oviposition site was based on the color of the container and was unaltered either by the degree of contrast between the container and its surroundings or by preconditioning the young females to only one color of container. Despite an apparent genetic basis for selection of white oviposition site, the strength of inheritance appeared weak. Many generations of selective breeding would be necessary to greatly after oviposition site choice behavior in this species.