The object of giving this list in its present imperfect form is to call the attention of our Entomologists to this greatly neglected order of insects, and as most of the families are still in an unworked condition, to call especial attention to them; of course, the named species represent only about one fourth of all the species taken by me during my three years collecting, and were mostly taken in Fairmount Park, and a few at Delanco, N. J.

If a few of our many Entomologists would turn their attention to the Diptera, they would be sure to find an interesting and very wide field, in fact there would be room enough for nearly a dozen systematic workers in this order.