Ordnung und Orientierung der Elemente im Sehsystem der Fliege

The neural elements in the visual ganglia of insects show an uncommonly high degree of order. The mapping of the array of sensory elements in the periphery (of sampling points in the visual space) onto four successive levels of the ganglionic chain can be quite precisely described, each neuron in the ganglia being related to a point, or a set of points, in the visual field. Also some of the fibers which connect neurons related to different visual-space-points are very precisely oriented. One of these sets of fibers oriented obliquely appear to match the interactions postulated on the basis of one of Götz‘s (1968) models of movement perception in flies. Some embryological questions are also raised by the high degree of order and by the curious mirror symmetry with respect to the mid-sagittal plane on one hand and to the equatorial plane on the other, which pervades the whole system