Fixation-sensitive areas in the eyes of the walking fly, Calliphora erythrocephala.

In Calliphora erythrocephala the visual fixation behaviour in one-eyed flies and partial blinded flies has been investigated. One-eyed flies show approximately the same stripe and edge fixation response as intact flies. Elimination of the frontal eye parts including the binocular field of vision does not effect the visual stripe fixation. On the other hand, if only the frontal areas of both eyes including the binocular field of vision are left open, no preferential direction can be observed (Fig. 1--3). The results imply the existence of a fixation-sensitive area of the eye located outside the binocular field of vision.