Though the ophthalmic surgeon, since the days when George Bartisch of Dresden wrote his celebrated "Augendienst," has almost wholly restricted his operative procedures to lesions within the orbital boundaries, he nevertheless has been obliged to look beyond the orbit into the territory of the neurologist for an explanation of many of the causes of disturbed vision. Helmholtz' discovery of the ophthalmoscope first made this possible, as von Graefe and Donders were quick to appreciate; and ere long the neurologists under the insistence of Hughlings Jackson and Gowers found that the routine examination of the fundus oculi was no less important to them than to the ophthalmologist. Thus the general employment of the ophthalmoscope for diagnostic purposes and the subsequent gradual development of perimetry by von Graefe, Förster, Bjerrum, Rönne and others served to emphasize the overlap between ophthalmology and neurology which had its first notable expression in