The sea-anemones first attract attention, showing as splashes of scarlet and salmon among the olive-green seaweed, or in hundreds covering the entire bottom of a pool with a delicately hued mist of waving tentacles. As the water leaves these exposed on the walls of the caves, they lose their plump appearance and, drawing in their wreath of tentacles, hang limp and shrivelled, resembling pieces of water-soaked meat as much as anything. Submerged in the icy water they are veritable animal-flowers. Their beauty is indeed well guarded, hidden by the overhanging seaweed in these caves twenty-five feet or more below high-water mark.
Here in these beautiful caverns we may make aquariums, and transplant as many animal-flowers as we wish. Wherever we place them their fleshy, snail-like foot spreads out, takes tight hold, and the creature lives content, patiently waiting for the Providence of the sea to send food to its many wide-spread fingers.
Carpeted with pink algæ and dainty sponges, draped with sea-lettuce like green tissue paper, decorated with strange corallines, these natural aquariums far surpass any of artificial make. Although the tide drives us from them sooner or later, we may return with the sure prospect of finding them refreshed and perhaps replenished with many new forms. For often some of the deep-water creatures are held prisoners in the lower tide-pools, as the water settles, somewhat as when the glaciers receded northward after the Ice Age there were left on isolated mountain peaks traces of the boreal fauna and flora.
If we are interested enough to watch our anemones we will find much entertainment. Let us return to our shrimp colonies and bring a handful to our pool. Drop one in the centre of an anemone and see how quickly it contracts. The tentacles bend over it exactly as the sticky hairs of the sun-dew plant close over a fly. The shrimp struggles for a moment and is then drawn downward out of sight. The birth of an anemone is well worth patient watching, and this may take place in several different ways. We may see a large individual with a number of tiny bunches on the sides of the body, and if we keep this one in a tumbler, before long these protuberances will be seen to develop a few tentacles and at last break off as perfect miniature anemones. Or again, an anemone may draw in its tentacles without apparent cause, and after a few minutes expand more widely than ever. Suddenly a movement of the mouth is seen, and it opens, and one, two, or even a half-dozen tiny anemones shoot forth. They turn and roll in the little spurt of water and gradually settle to the rock alongside of the mother. In a short time they turn right side up, expand their absurd little heads, and begin life for themselves. These animal “buds” may be of all sizes; some minute ones will be much less developed and look very unlike the parent. These are able to swim about for a while, and myriads of them may be born in an hour. Others, as we have seen, have tentacles and settle down at once.
Fishes, little and big, are abundant in the pools, darting here and there among the leathery fronds of “devils’ aprons,” cavernous-mouthed angler fish, roly-poly young lump-suckers, lithe butterfish, and many others.
Moving slowly through the pools are many beautiful creatures, some so evanescent that they are only discoverable by the faint shadows which they cast on the bottom, others suggest animated spheres of prismatic sunlight. These latter are tiny jelly-fish, circular hyaline masses of jelly with eight longitudinal bands, composed of many comb-like plates, along which iridescent waves of light continually play. The graceful appearance of these exquisite creatures is increased by two long, fringed tentacles streaming behind, drifting at full length or contracting into numerous coils. The fringe on these streamers is a series of living hairs—an aquatic cobweb, each active with life, and doing its share in ensnaring minute atoms of food for its owner. When dozens of these ctenophores (or comb-bearers) as they are called, glide slowly to and fro through a pool, the sight is not soon forgotten. To try to photograph them is like attempting to portray the substance of a sunbeam, but patience works wonders, and even a slightly magnified image of a living jelly is secured, which shows very distinctly all the details of its wonderfully simple structure; the pouch, suspended in the centre of the sphere, which does duty as a stomach; the sheaths into which the long tentacles may be so magically packed, and the tiny organ at the top of this living ball of spun glass, serving, with its minute weights and springs, as compass, rudder, and pilot to this little creature, which does not fear to pit its muscles of jelly against the rush and might of breaking waves.
Even the individual comb-plates or rows of oars are plainly seen, although, owing to their rapid motion, they appear to the naked eye as a single band of scintillating light. This and other magnified photographs were obtained by fastening the lens of a discarded bicycle lantern in a cone of paper blackened on the inside with shoe-blacking. With this crude apparatus placed in front of the lens of the camera, the evanescent beauties of these most delicate creatures were preserved.
Other equally beautiful forms of jelly-fish are balloon-shaped. These are Beröe, fitly named after the daughter of the old god Oceanus. They, like others of their family, pulsate through the water, sweeping gracefully along, borne on currents of their own making.
Passing to other inhabitants of the pools, we find starfish and sea-urchins everywhere abundant. Hunched-up groups of the former show where they are dining in their unique way on unfortunate sea-snails or anemones, protruding their whole stomach and thus engulfing their victim. The urchins strain and stretch with their innumerable sucker-feet, feeling for something to grasp, and in this laborious way pull themselves along. The mouth, with the five so-called teeth, is a conspicuous feature, visible at the centre of the urchin and surrounded by the greenish spines. Some of the starfish are covered with long spines, others are nearly smooth. The colours are wonderfully varied,—red, purple, orange, yellow, etc.
The stages through which these prickly skinned animals pass, before they reach the adult state, are wonderfully curious, and only when they are seen under the microscope can they be fully appreciated. A bolting-cloth net drawn through some of the pools will yield thousands in many stages, and we can take eggs of the common starfish and watch their growth in tumblers of water. At first the egg seems nothing but a tiny round globule of jelly, but soon a dent or depression appears on one side, which becomes deeper and deeper until it extends to the centre of the egg-mass. It is as if we should take a round ball of putty and gradually press our finger into it. This pressed-in sac is a kind of primitive stomach and the entrance is used as a mouth. After this follows a marvellous succession of changes, form giving place to form, differing more in appearance and structure from the five-armed starfish than a caterpillar differs from a butterfly.