About 8 months ago I finished my monograph of the Megaloptera (Sialidae) for the „Catalogue des Collections Zoologiques du baron E. de Selys Longchamps.” Though the work is since ready for the press, it cannot yet be printed. As there are many new genera and species described in it and because other workers in this interesting family might describe them before my monograph has been published, I give here short descriptions of them in order to secure their priority. This order of insects, separated from the other Neuroptera and especially from the Planipennia under the name of Megaloptera, contains two families: the primitive Sialidae and the much higher specialised Raphidiidae.