Seagrass

“ Now we come to the real use of sea plants. They are food for all the hosts of small animals of the sea. These eat it as it grows; or else, like the mussel and oyster, swallow the tiny scraps of it which float everywhere like so much dust.
The shell-fish, and other animals which feed on sea plants, are themselves eaten by other sea creatures, and these in their turn are eaten by crabs, lobsters and fish, which are eaten by us. It reminds you of a chain. The first link in the chain is the sea plant, the last links are the fish and ourselves. ”

“ The hard sand which the tide has left is pitted with tiny holes, the lairs of a million crabs and sea insects. The beaches are covered with a wondrous diversity of animal and vegetable growths thrown up and discarded by the tide. Seaweed of strange varieties, and of every fantastic shape and texture, the round balls of fibrous grass, like gigantic thistledowns, which scurry before the light breeze, as though endued with life, the white oval shells of the cuttle-fish, and the shapeless hideous masses of dead medusæ, all lie about in extricable confusion on the sandy shores of the East Coast. ”

“ And now the dawn is on our pillow—hide
Your eyes—I shiver—they are haggard, wide!
SEA-SCAPE.
Under basaltic porticoes of calm sea-caves,
Heavy with alga and the moss of fucus gold,
In the occult, slow shaking of sea-waves,
Among the alga in proud blooms unfold
[Pg 33] The cups of pride of silent, slender gladioles....
The mystery wherein dies the rhythm of the waves
In gleams of kisses long and calm unrolls,
And the red coral whereon writhes the alga cold
Stretches out arms that bleed with calm flowers, and beholds
Its gleams reflected in the rest of waves. ”

“ There will be shoals of fish, too, playing in and out, as strange and gaudy as the rest,—parrot-fish who browse on the live coral with their beak-like teeth, as cattle browse on grass; and at the bottom, it may be, larger and uglier fish, who eat the crabs and shell-fish, shells and all, grinding them up as a dog grinds a bone, and so turning shells and corals into fine soft mud, such as this stone is partly made of. ”

“ Are these sprays of pink coral? No, they are sea-rods and branches. If you pinch the thick stems, water will ooze out, for they are partly hollow, like the pond-lily stem.
I do not wonder you look with questioning surprise at that next plant. It is like a mass of purple bushes, a very sweet growth rather hard to describe. All through the delicate branches are what look like small dark berries, seen through a mist of pinkish, hairy spires.
Don't start. These merry fishes darting through the next clump of bushes have only come to smell of the carnation pinks the bushes bear. ”

“ And by and by we reach the sea, and there we find masses of tangled seaweed, the plants of the salt water, while all along the shores myriads of living creatures are left by the receding tide. In the rocky pools we find active life busily at work. Thousands of tiny acorn shells, scarcely larger than the head of a good-sized pin, cover the rocks and fling out their thread-like arms in search of food. ”

“ Then there are coral islands in the Pacific Ocean, whole platforms of solid coral which shut in portions of quiet water in some places.
The little corals themselves do not work in deep water, nor above the surface of the sea. But the bony substance spreads and spreads, up, down, and across the sea. And as many shell-fish eat into coral, great quantities of fine coral-sand sink to the bottom, making a nice white carpet for the fishes to glide over. Folks do not take coral from the sea at any time but during the months you call April, May, and June. ”

“ Half an hour after the Canadian’s latest exploits, we were back on the inner beach. There the local flora was represented by a wide carpet of samphire, a small umbelliferous plant that keeps quite nicely, which also boasts the names glasswort, saxifrage, and sea fennel. Conseil picked a couple bunches. As for the local fauna, it included thousands of crustaceans of every type: lobsters, hermit crabs, prawns, mysid shrimps, daddy longlegs, rock crabs, and a prodigious number of seashells, such as cowries, murex snails, and limpets. ”

“ Sharks in all their fearsome varieties prowled greasily about, scenting for dead things whereon to gorge, shell-fish from the infinitesimal globigerina up to the gigantic clam whose shells were a yard each in diameter; crabs, lobsters, and other freakish varieties of crustacea of a size and ugliness unknown to day lurked in every crevice, while about and among all these scavengers flitted the happy, lovely fish in myriads of glorious hues matching the tender shades of the coral groves that sprang from the summits of those sombre lava columns beneath. ”

“ In warm seas the most conspicuous of rock-making organisms are the corals known as the reef builders. Floating in a boat over a coral reef, as, for example, off the south coast of Florida or among the Bahamas, one looks down through clear water on thickets of branching coral shrubs perhaps as much as eight feet high, and hemispherical masses three or four feet thick, all abloom with countless minute flowerlike coral polyps, gorgeous in their colors of yellow, orange, green, and red. ”

“ Divide them carefully, clear out the oysters with a knife, and put the shells into your aquarium, and you will find that an oyster at home is a very different thing from an oyster on a stall.
You ought, besides, to dredge many handsome species of shells, which you would never pick up along the beach; and if you are conchologizing in earnest, you must not forget to bring home a tin box of shell sand, to be washed and picked over in a dish at your leisure, or forget either to wash through a fine sieve, over the boat’s side, any sludge and ooze which the dredge brings up. ”

“ In the pool itself a beautiful lavender-colored jelly-fish was floating about, and just beyond lay a star-fish clinging to a bunch of seaweed. She found other treasures scattered about by the largess of the tide—tiny spiral shells, stones of all colors, and a horseshoe crab, besides seaweed with pretty little pods which popped delightfully when she squeezed them with her fingers. ”

“ For there is an interesting give and take between the shore-haunt and the open sea. From the shore come nutritive contributions and minute organisms which multiply quickly in the open waters. But not less important is the fact that the open waters afford a safe cradle or nursery for many a delicate larva, e.g. of crab and starfish, acorn-shell and sea-urchin, which could not survive for a day in the rough-and-tumble conditions of the shore and the shallow water. After undergoing radical changes and gaining strength, the young creatures return to the shore in various ways. ”

“ The bed of the ocean, from the tiny lakelets left by the retiring tide to the greatest depths ever reached by trawl and dredge, is found to be teeming with exquisite forms of life. Delicate plant-like forms are found clinging to rocks and shells, or spreading themselves over the broad fronds of the algae. Every peculiarity of vegetation is mimicked; graceful stems rising from tangled roots send out branches which bear raceme-like clusters of buds, and delicate bells whose beauty no words can describe.
Fig. 5.—Roving Medusa of Tubularia indivisa. ”

“ Here will be found hydroids, sea-anemones, starfishes, sea-urchins, barnacles, mussels. In the shallow water, crabs and shrimps are crawling along the sandy bottom or are lying concealed in the mud, while schools of little fishes scoot across the pool. If a fine silk net is drawn through the water and then emptied into a glass dish a whole new world of creatures will be revealed—jellyfishes, ctenophores, hydroids, eggs of fish, tiny copepods, the larvae or young of sea-urchins, starfishes, or oysters. ”

“ Seaweeds belong to a humble family in the world of plants, having no real roots, no flowers, and no real seeds. They can attach themselves to the stones or rocks. Along comes a great wave, and perhaps they are torn up; but this does not harm them, for they still live as they wash to and fro in the water, until they cling to another rock. Or they are thrown on the shore to die, or else to be washed back to sea by the next tide.
SEA-WEED FROND.
The Sea Lettuce or Green Laver is a common seaweed near the shore. ”

“ With the exception of the algae and a few representatives of other classes of plants, which live in the shallow-water belt round the coast, or in inland lakes and seas, plants are confined to land-surfaces; and unless their remains are swept along by streams and embedded in sediments which are accumulating on the sea floor, the chance of their preservation is but small. The strata richest in fossil plants are often those which have been laid down on the floor of an inland lake or spread out as river-borne sediment under the waters of an estuary. ”

“ They grow on the rocks, in pretty coloured tufts.
If you dive still farther, into the dark depths of the sea, you find beds of ooze and slime, and rocks and weird fishes, but no plants. Why is this? Like the land-plants, these sea-plants must have light. They cannot grow in the blackness of very deep water. Can you guess why some sea-weeds are green and others red? Those growing in the shallow water of the shore are green, like land-plants, because the sunlight reaches them. Only part of the light can pass through deep water; and so, in these shady places, the sea-weed is reddish in colour. ”

“ These grow in greatest luxuriance outside the harbour where the water is of astonishing clarity. It is owing to the vigour of their growth that the edge of the reef is nearly a vertical wall, so that looking down strange beautiful shapes are seen one below another, weird fish entering and leaving their lairs under the coral tangle, till in the pure blue depths the forms of coral and fish become indistinct and pass into the haze of water 60 feet or more deep. ”

“ You are right, Fritz; coral consists of the calcareous cells of minute animals, so built up as to form a tree-like structure.
“The coral fishery gives employment to many men in the Persian Gulf, the Mediterranean Sea, and other places. The instrument commonly used, consists of two heavy beams of wood, secured together at right angles, and loaded with stones. Hemp and netting are attached to the under side of the beams, to the middle of which is fastened one end of a strong rope, by which the apparatus is let down from a boat, and guided to the spots where the coral is most abundant. ”

“ The bed of the seas is alive with polypes, crabs, star-fishes, and with sand-numerous shell-animalcules. The rugged face of rocks is scarred by the silent boring of soft creatures; and blackened with countless mussels, barnacles, and limpets. ”

“ And the submarine rocks or shores of these new formations of land became covered with aquatic vegetables, on which various species of shell-fish and common fishes found their nourishment. The fluids of the globe in cooling deposited a large quantity of the materials they held in solution, and these deposits agglutinating together the sand, the immense masses of coral rocks, and some of the remains of the shells and fishes found round the shores of the primitive lands, produced the first order of secondary rocks. ”

“ Coral growth will be most luxuriant in the shallow water, and the first stage of our reef will be a mound of coral of the shape shewn in section by the dotted area. Between E and D this comes to the surface, and the corals, projecting above the water at lowest spring tides, are killed at the top, so that E to D becomes an almost flat surface of dead corals, some of which may, however, be still living where their bases are immersed in clear sea-water. ”

“ For wherever the sun strikes the plants are more frequent, and superior, and more delicate, as in gardens, and the black shore-weed grows near the land, and the other kinds rather resemble uncultivated plants. The neighbourhood of the coast is also more temperate, both in heat and cold, than the rest of the sea; for which reason the flesh of fish which live near the shore is more compact, while that of fish from deep sea is watery and soft. The sinodon, cantharus, orphos, chrysophrys, cestreus, trigla, cichla, dracon, callionymus, cobius, and all the rock fish live near the shore. ”

“ From the simplicity of diatoms the vegetation of the sea can be traced upward through larger and more complicated kinds of plants until we reach the enormous algæ that break the gloom of black headlands by their brilliant tints, and furnish a lurking-place under their wide-spreading and dense foliage for hosts of marine animals—some hiding for safety, others to watch for prey.
Seaweeds grow in all latitudes, even close to the pole, but mainly along the shore, for below the depth of about one hundred fathoms none but microscopic forms are known. ”

“ When near the coast they conceal themselves between corals, stones, or fucus, holding on to the ground by means of their arm-like pectoral fins. Their coloration is so similar to their surroundings that it is hardly possible to distinguish the fish from a stone or coral overgrown with vegetation. Their way of attracting and seizing their prey is evidently the same as in the other fishes of this family. The extraordinary range of some of the species which inhabit the Atlantic as well as the Indo-Pacific Oceans, is the consequence of their habit of attaching themselves to floating objects. ”

“ Prawns, Shrimps, Medusae, and fishes of many species, in the little pools which the tide leaves behind, and which it will require a sharp eye and a quick hand to explore with success. But the rarer forms of Actinias, Star-fishes, Sepioles, Madrepores, Annelidae, and Zoophytes, of a thousand shapes, live on the bottom, in deep water, and must be captured there.
For this purpose we must dredge from a boat, under sail. The naturalist's dredge is an improved oyster-dredge, with each of the two long sides of the mouth made into a scraping lip of iron. ”