During the summer of 1896 I received specimens of ants collected by Mr. R. J. Crew, of Toronto, in exchange for such Coleoptera as I could find for him in my locality. He writes me that he noticed no insects with the ants other than the Coleopteta and some aphids in a nest of ants, but did not capture any.I have found, however, upon looking them over, they contain several very interesting species of various orders: some truly myrmecophilous, some occasional, while others were brought into the nests by the ants, to be used by them for food; this will apply to a number of Hemiptera collected by Formica subsericea, Say.