A new gall midge (Dipt., Cecidomyidae) predaceous on the Flour Mite, Tyroglyphus farinae (Deg.)

Owing to the courtesy of Miss H. Dombrowski (E. V. Dombrovskaya) of the Zoological Institute of the Academy of Science, Leningrad, U.S.S.R., it is now possible to describe a sixth species of gall midge belonging to the genus Trisopsis Kieffer. Males, females and larvae of this species were received from Russia in April, 1937. The larvae had been found during the previous winter preying on the Flour Mite, Tyroglyphus farinae (Deg.) during laboratory observations on the predaceous mite, Cheyletus eruditus (Schr.), which had been kept with the flour mites in paraffin wax cells at the Institute for Plant Protection, Leningrad (Sorokin, 1938).