Abstract
Knowledge of the breeding habits of the Anopheline mosquitos has advanced greatly since the days when it was considered that the larvae of any species were distributed indiscriminately in all and sundry collections of stagnant water. In the Federated Malay States entomological research, which has now extended over many years, tends to show that preferences by the various species for different kinds of breeding-places exist; and attempts have been made to define in relation to particular species, or groups of species, or groups of species, the types of breeding-place favoured.