The family Scatophagidae, which is richly represented in the northern parts of America and the Old World, is particularly well represented in Canada and most of the species described from America occur in this country. At least some of our species referred to genera established for Palaearctic forms belong doubtfully to these genera and the determination of species is rendered very difficult because the majority of our species have been described in the genus Cordilura. An examination of Loew's types has enabled me to place his species and to determine that a great many of those in the Canadian National Collection are undescribed and descriptions of some of these are now given. Others will be described in a complete revision of the family now under preparation.