C.D. Warner, et al., comp. The Library of the World’s Best Literature.
An Anthology in Thirty Volumes. 1917.
Color and Form in the Ceylon Coral Banks
By Ernst Haeckel (1834–1919)
N
Ransonnet had already pointed out how singularly and universally green prevails in the coloring of Ceylon. Not only is the greater portion of this evergreen isle clothed with an unfading tapestry of rich verdure, but the animals of the most widely dissimilar classes which live in its woods are conspicuous for their green coloring. This is seen in all the commonest birds and lizards, butterflies, and beetles, which are of every shade of brilliant green. In the same way the innumerable inhabitants of the sea, of all classes, are colored green, such as many fishes and crustacea, worms, and sea-anemones: indeed, creatures which elsewhere seldom or never appear in green livery wear it here; for instance, several star-fish, sea-urchins, sea-cucumbers; also some enormous bivalves, and Brachiopoda, and others. An explanation of this phenomenon is to be found in Darwin’s principles, particularly in the law of adaptation by selection of similar coloring or sympathetic affinity of color, as I have elucidated it in my ‘History of Creation.’ The less the predominant coloring of any creature varies from that of its surroundings, the less will it be seen by its foes, the more easily can it steal upon its prey, and the more it is protected and fitted for the struggle for existence. Natural selection will at the same time constantly confirm the similarity between the prevailing color of the animal and of its surroundings, because it is beneficial to the animal. The green coral banks of Ceylon, with their preponderance of green inhabitants, are as instructive in their bearing on this theory as are the green land animals which people the evergreen forests and thickets of the island; but in purity and splendor of coloring the sea creatures are even more remarkable than the fauna of the forests.
It would, however, be a mistake to suppose that this prevailing green hue produces a monotonous uniformity of coloring. On the contrary, it is impossible to weary of admiring it; for on the one hand, the most wonderful gradations and modifications may be traced through it, and on the other, numbers of vividly and gaudily colored forms are scattered among them. And just as the gorgeous red, yellow, violet, or blue colors of many birds and insects look doubly splendid in the dark-green forest of Ceylon, so do the no less brilliant hues of some marine creatures on the coral banks. Many small fishes and crustaceans are particularly distinguished by such gaudy coloring, with very elegant and extremely singular markings, as they seek their food among the ramifications of the coral-trees. Some few large corals are also conspicuously and strikingly colored; thus, for instance, many Pocilloporæ are rose-colored, many of the Astræidæ are red and yellow, and many of the Heteroporæ and Madreporæ are violet and brown, etc. But unfortunately, these gorgeous colors are for the most part very evanescent, and disappear as soon as the coral is taken out of the water; often at a mere touch. The sensitive creatures which have displayed their open cups of tentacles in the greatest beauty then suddenly close, and become inconspicuous, dull, and colorless.
But if the eye is enchanted merely by the lovely hues of the coral reef and its crowded population, it is still more delighted by the beauty and variety of form displayed by these creatures. Just as the radiated structure of one individual coral polyp resembles a true flower, so the whole structure of the branched coral stock resembles the growth of plants, trees, and shrubs. It was for this reason that corals were universally supposed to be really plants, and it was long before their true nature as animals was generally believed in.
These coral gardens display indeed a lovely and truly fairy-like scene, as we row over them in a boat at low tide and on a calm sea. Close under the Fort of Galle the sea is so shallow that the keel of the boat grates on the points of the stony structure; and from the wall of the fort above, the separate coral growths can be distinguished through the crystal water. A great variety of most beautiful and singular species here grow close together, on so narrow a space that in a very few days I had made a splendid collection.
Mr. Scott’s garden, in which my kind host allowed me to place them to dry, looked strange indeed during these days. The splendid tropical plants seemed to vie with the strange marine creatures who had intruded on their domain for the prize for beauty and splendor; and the enchanted naturalist, whose gladdened eye wandered from one to the other, could not decide whether the fauna or the flora best deserved to take it. The coral animals imitated the forms of the loveliest flowers in astonishing variety, and the orchids on the other hand mimicked the forms of insects. The two great kingdoms of the organized world seemed here to have exchanged aspects.
Most of the corals which I collected in Galle and Belligam, I procured by the help of divers. These I found here to be quite as clever and capable of endurance as the Arabs of Tur nine years before. Armed with a strong crowbar, they uprooted the limestone structure of even very large coral stocks from their attachment to the rocky base, and raised them most skillfully up to the boat. These masses often weighed from fifty to eighty pounds, and it cost no small toil and care to lift them uninjured into the boat. Some kinds of coral are so fragile that in taking them out of the water they break by their own weight; and so, unfortunately, it is impossible to convey many of the most delicate kinds uninjured to land. This is the case, for instance, with certain frail Turbinariæ, whose foliaceous stock grows in the shape of an inverted spiral cone; and of the many-branched Heteropora, which resembles an enormous stag’s antler with hundreds of twigs.
It is not from above, however, that a coral reef displays its full beauty, even when we row close over it, and when the ebb-tide has left the water so shallow that its projections grind against the boat. On the contrary, it is essential to take a plunge into the sea. In the absence of a diving-bell I tried to dive to the bottom and keep my eyes open under water, and after a little practice I found this easy. Nothing could be more wonderful than the mysterious green sheen which pervades this submarine world. The enchanted eye is startled by the wonderful effects of light, which are so different from those of the upper world with its warm and rosy coloring; and they lend a double interest and strangeness to the forms and movements of the myriads of creatures that swarm among the corals. The diver is in all reality in a new world. There is in fact a whole multitude of singular fishes, crustacea, mollusca, radiata, worms, etc., whose food consists solely of the coral polyps among which they live; and these coral-eaters, which may be regarded as parasites in the true sense of the word, have acquired by adaptation to their peculiar mode of life the most extraordinary forms; more especially are they provided with weapons of offense and defense of the most remarkable character.
But just as it is well known that “no man may walk unpunished under the palms,” so the naturalist cannot swim with impunity among the coral banks. The Oceanides, under whose protection these coral fairy bowers of the sea flourish, threaten the intruding mortal with a thousand perils. The Millepora, as well as the Medusæ which float among them, burn him wherever they touch like the most venomous nettles; the sting of the fish known as Synanceia is as painful and dangerous as that of the scorpion; numbers of crabs nip his tender flesh with their powerful claws; black sea-urchins thrust their foot-long spines, covered with fine prickles set the wrong way, into the sole of his foot, where they break off and remain, causing very serious wounds. But worst of all is the injury to the skin in trying to secure the coral itself. The numberless points and angles with which their limestone skeleton is armed, inflict a thousand little wounds at every attempt to detach and remove a portion. Never in my life have I been so gashed and mangled as after a few days of diving and coral-fishing at Galle, and I suffered from the consequences for several weeks after. But what are these transient sufferings to a naturalist, when set in the scale against the fairy-like scenes of delight with which a plunge among these marvelous coral groves enriches his memory for life!