The first species to be dealt with was received from M. Prosper Bovien, of the Statens Plantepatologiske, Forsøg, Lyngby, in October 1927. It was reared from larvae and pupae found abundantly among seed of radish (Raphanus sativum) that had been in storage for months, and it was thought that the larvae were preying on the mites (Aleurobius, etc.) which attack the seed. In a later letter it was stated that some years previously the midges were observed emerging in January from seed in which there were no Aleurobius but numerous Cheyletus. The midge occurs at irregular intervals in seed from Denmark, as well as in seed from Germany.