3. “On the Hessian Fly,” by W. M. Maskell, F.R.M.S. Abstract. The identification of the wheat fly sent down from the Rangitikei District with the true Hessian fly (Cecidomyia destructor) is a matter of some importance. The larva, or maggot, answers entirely to that of C. destructor, possessing the peculiar appendage beneath the head, called the breast-bone, characteristic of the Hessian fly. The author had, at first, some doubt as to the veining of the wings, but has since been able to satisfy himself that the real Hessian fly has reached these islands. The Hessian fly is, however, subject to much damage from the attacks of other insects- parasites as they are called. The author reported that in New Zealand it had no sooner arrived than it was attacked by parasites in the form of hymenopterous insects, probably of the family Proctotrupida, and indigenous to New Zealand.