On February 13, 1955, a collection of galls was taken from a row of willow shrubs, Salix sp., growing in a ditch on the west side of Adelaide Street between the sixth and seventh Concession lines of London Township, Middlesex County, Ontario. The galls ranged in size from about one inch to one and a half inches long and were fusiform in shape with a slightly curved beak at the tip (Fig. 1, 2, 3). They were identified, with keys and descriptions of galls of willow in Felt (1912, 1940), as beaked willow gills caused by the fly Phytophaga rigidae (O.S.). Several galls were split open, disclosing in each a narrow central chamher which was closed at its lower end and which opened at its upper end through the beak. In the chamber was an orange larvae, about 7 mm. long, with its anterior end toward the opening of the chamber. It was recognizable as an itonidid larva because of the presence on it of the “breast-plate” typical of larvae of the family Itonididae.