“黄色水晶体”魚アオメエソの眼について

Abstract

It has been shown that the deep-sea fish Chlorophthalmus albatrossis, which lives at a depth of 200m to 400m, has some interesting characteristics on its eyes. 1. Chlorophthalmus has yellow lens. The absorption spectrum of the yellow lens measured revealed an absorption maximum at about 400nm. This peak is not detected in the colorless lens of Argentina semifasciata. 2. Both cones and rods are present in the retina. All the cones examined had been twin cones and are concentrated in the ventral part of the retina. 3. From the distribution of the visual cells, the retina is divided into three areas; the first is the twin cone area, the second is the horizontal line area, and the third is the rod area. 4. Our observations on the form of the head, the position of the eyes, and the structure of the retina, indicate that the visual axis of the eye is directed upward. 5. The functional significance of the twin cone is discussed.