During the last few months I have been engaged in examining the remains of the fossil Vertebrates from the Middle and Upper Eocene of the Fay ûm district of Egypt, with a view to the preparation of the detailed monograph which it is proposed to publish on this subject. As it will be some months before this can appear, it seems desirable to give a brief account of some of the more important results arrived at, and preliminary descriptions of such new forms as have come to light in the course of the work. The collections examined include all the material belonging to the British Museum, as well as many of the more important specimens from the Geological Museum of Cairo. There still remains in Cairo a large collection of bones, which I hope to have an opportunity of working out during the next few weeks.