Fig. 4. Comparison of dorsal rim retinulae with nearby retinulae of the yellow retina in the same section stained with anti-P357 and photographed with phase interference optics to enhance images of rhabdoms. (A) Dorsal rim retinulae with typical butterfly-shaped rhabdoms. Note the absence of surrounding tracheoles. The narrow ventral dv cell is stained in the retinula on the far right. (B) Retinulae surrounded by tracheoles (t) from an adjacent region of the yellow retina. Two dv cells are stained in the retinula on the far left; only one cell is stained in the other retinulae. Scale bar, 1 µm.