Читать книгу Life at the Zoo: Notes and Traditions of the Regent's Park Gardens онлайн

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The phosphorescent power is by no means confined to the fishes proper of the deep sea. Starfish and most of the various forms of zoophytes possess it, though in less perfect organs. One poured out “clouds of a pale-blue, highly luminous substance, which not only illuminated the observer’s hands and surrounding objects in the vessel in which it was confined, but finally communicated a luminosity to the water itself;” another threw out light of a brilliant green, coruscating from the centre, now along one arm, now along another. In view of the phosphorescence even of the surface of the sea when full of luminous creatures, it is not rash to conclude that the eternal night of the abyss is in places lighted with sufficient brilliance by its phosphorescent zoophytes and fishes. Where these are few or absent, there must be darkness either partial or complete. Hence we are presented with the perfectly reconcilable contradiction of deep-sea creatures with eyes of high development, and others with no eyes at all; one species possessing eyes with four thousand facets, while crabs and prawns are found totally blind, like the fish of subterranean caverns. Those which carry lamps themselves, or live among luminous creatures, not only retain their eyes, but are supplied with organs of abnormal power in order to use to the utmost the phosphorous beams. The presence of bright colouring in the deep-sea forms is also explained in the same way, so far as colour is related to the presence of light. There is little difference in the hues of deep-sea and shallow-water species, except that shades of red are more frequent in the former, possibly because red is the complementary colour of the phosphorescent beams.