. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 376 BERNARD J. BOWDEX The luminescence. Whenever the animal is disturbed, as by shaking in a vessel or tapping the shell, luminous mucus appears in all parts of the groove be- tween the foot and the mantle. This is visible even in diffused daylight as a greenish glow, and in the dark the effect is much more striking. The animals have never been seen to luminesce spontaneously at night either in the laboratory or in their natural habitat, but when they are stimulated they produce the glow equally well during the day or night.
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 376 BERNARD J. BOWDEX The luminescence. Whenever the animal is disturbed, as by shaking in a vessel or tapping the shell, luminous mucus appears in all parts of the groove be- tween the foot and the mantle. This is visible even in diffused daylight as a greenish glow, and in the dark the effect is much more striking. The animals have never been seen to luminesce spontaneously at night either in the laboratory or in their natural habitat, but when they are stimulated they produce the glow equally well during the day or night. Where the mantle groove is touched with a seeker, that region in particular glows most strongly. Shaking the animal in a test tube or rubbing it, foot down, across a glass slide produces trails of glowing mucus from which the light slowly fades. Vise FIGURE 3. Outline of a transverse section (camera lucicla). The crosses show the approxi- mate number and distribution of granular cells. ( These represent the average distribution in six non-consecutive sections from the same specimen.) Muse., muscular mass of the foot. Vise., viscral hump. (Other letters as for Figs. 1 and 2.) Clearly then the phenomenon is an extracellular one, and experiments to deter- mine the nature of the luminescence show that it depends on the action of luciferase upon the substrate luciferin, which appear to be produced together from specific areas, particularly along the walls of the mantle groove. Histology. Examination of the sectioned animal shows that certain parts of its surface present a very striking and characteristic appearance. These regions are the surface of the head, the anterior tentacles, the lateral surfaces of the foot, the inferior pallial lobe, and the free surface of the mantle (but not of the pulmonary cavity). Tn all these situations, just beneath the simple cuboidal surface epithelium and lying in the loose subepithelial connective tissue, are large numbers of inter- mingl
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
