Photoreceptor processes were not uniform in size across the retina. They were thick, up to 8 lm, and short in the posterior region in the posterior eye, but thin, down to
6 lm, in the anterior region (Figs. 7 and 8). Similarly, in the anterior eye they were thicker in the anterior region and thin in the posterior region of the retina. As far as the entire visual field of the larva in ambushing posture was concerned, the field above the head (where the visual fields of anterior and posterior eyes overlapped) wasviewed by thick photoreceptor processes. By contrast, the anterior and posterior directions of the visual field were viewed by thin photoreceptor processes in just the anterior and posterior eyes, respectively.