A PHOSPHORESCENT CORAL AND OTHER MARINE PHOS-ANIMALS.

Waikato Times, Volume XIX, Issue 1598, 30 September 1882, Page 2

A PHOSPHORESCENT CORAL AND OTHER MARINE PHOS-ANIMALS.

BX 0. F. HOLDER. This appearance of phosphorescent light among corals is of extremely rare occurrence, and during a long residence in the coral country, and of continued observation, the phenomenon was only observed once, and that in the genius Garyophilla. The specimen was first seen from the boat in about thirty feet of water, and brought up by diving, by the writer, and immediately placed in a jar of water, and finally transferred to an aquarium that had been built so that the tide rose and fell in it. Here the beautiful specimen was lodged, so that every movement of the animal could be observed. It had five branches, each one forming a cell showing beautiful radiating plates, striated externally, and collected into a solid conical polyparium fixed at the base. The appearance of the animal when extended, though extremely attractive, did not come uu to the one described by Professor Johnson, of JJondon. "When taken," he, says, referring to one dredged in deep water by Professor Travers, " the animal was scarcely visible,' being contracted ;- > whenl, 'expanded', the disk^vas, conspicuously- marked . v byl?two dentated circlea^birigli^apple.greWj.the one. marginal, and/outside' the^ntacula; the pther ; at, -Some '• distance < ixojA .;the \ transverse- and*

under the surface, > and a platform had been arranged bo that the observer could watch it from the water's edge, and while so doing the light was first seen. At first we- thought it might have been the phosphorescent flash of some minute acaleph, myriads of which were floating about, but to remove all doubt a glass funnel, slightly tinted, was gently lowered down over it, and a second later a slight flash, illuminated it, and then another, showing a faint light that made small objects visible in the immediate vicinity of the polyp; and _ at one time a petropod was suddenly thrown into a brilliant light when within a few inches of it. The flashes seemed to be intermittent, and to prevade the entire face of the cell in much the same fashion as does the light of the firefly tho surface of that insect. By lowering a black glass near it an idea was obtained of the size of the reflection which was on the glass, an oval illuminated spot seemingly about, the size of a silver quarter, and the color of the spark yellow, with perhaps a bluish tint. The cause of this most singular and curious phenomenon is probably the same here, in a general sense, as in other forms. ;Perhaps there aro special organs, as has been •suspected in some of the acelphs, or it may be due to some fatty degeneration of the parts. In the sea pens (Pcnnatulidoa) the same phenomenon has been noticed, and a recent Arctic exploration discovered one of these curious creatures growing about four feet in height in water nearly a mile deep. The one known to Science as JRcnilla reniformis is a rich purple species found off the coast of South Carolina. According to Agassiss it is remarkably phosphorescent, showing a golden green light of wonderful softness. Another — the Pcnnatula phosphorca — is found in European waters of a rich red-purple color. Dr. Grant, in speaking of them, says: — "A more singular and beautiful spactaclc could hardly be conceived than that of a deep purple (P. phosphorea), with all its delicate transparent polypi expanded and emitting their usual brilliant phosphorescent light, sailing through the still and dark abyss, by the regular and synchronous pulsations of the minute fringed arms of the whole polypi." Linicus says that "the plio&phorscenl sea pens which cover the bottom of the ocean cast so strong a light that it is easy to count the fishes and worms of various kinds that sport among them." One observer has been fortunate in discovering evidence of phosphorscent light in the boring mullosk pholas, having seen a faint flame or light playing about the entrance to its retreat; but the most wonderful of all the light-givers of tho ocean are certain forms of ascidians. A compound one, the Pijrosoma, has been found, in the shape of a barrel, nearly five feet in length — an aggregation of many thousands of individuals. Huxley says of this interesting form : " The ascidiarium of Pyrosoma has Iho form of a hollow cylinder, rounded and closed at one end, truncated and open at the other, formed of a firm and transparent texture, in which the zooids are arranged in whorls ; their oval apertures open on the exterior surface, and their atrial apertures into the interior of the cylinder. * The hremal aspect of each zooitl is turned toward the closed end of the cylinder. The "branchial sac has tho ordinary structure, and each zooid is provided with a testis and with an ovisac containing a single ovum." To move along each zooitl draws in water through its oval aperture and discharges it into the interior of the cylinder. The effect of so many currents being forced out of the open end propels the whole mass ahead, in the direction it happens to take. Each of these zooids sometimes shiuec with a brilliant flame, so that at a distance through the water they have the appearance of great fire balls moving to and fro. The naturalist Bennet thus speaks of them: "I threw the towing net over the stern of the ship, which soon cleaved through the brilliant mass, the disturbance causing strong flashes of light to be emitted. On taking the towing net in it was found to.be half filled with Phrywma atlanticum, which shone with a beautiful pale greenish light. After the mass had been passed through by the ship the light was still seen astern. The second occasion of my meeting these creatuses," he says, "was in high latitude and during the winter season. It was on the 19th of August, the weather dark and gloomy, with light breezes from north-north-east, in lat. 40 cleg. 30 rnin. S. andjl3B cleg. 3 mm. E. long., at the west entrance of Bass's Straits, and about eight o'clock, when the ship's wake was perceived to be luminous, while scintilations of the same light were abundant all around. To ascertain the cause I threw the towing net overboard, and in twenty minutes suceceded in capturing several pyrosoma, which gave out their usual pale green light ; and it was no doubt detached groups of these am'mals which were tho occasion of the lights in question." Humboldt also attests to the wonders of the colony of animals : " Only imagine," he says, " the superb spectacle we enjoyed when, in the evening from six to eleven o'clock, a continuous band of those living globes of fire was passing near our vessel. With tho light which they diffused we could distinguish at a depth of fifteen feet the individuals of thymnurf, pelamys, and sarclon, which have followed us these several weeks, notwithstanding tho celerity with which we sailed. Among these are other free swimming ascidians, as the salpa — animals that join in long bands, and from the masthead look like fiery serpents, winding their way through the sea. Myriads of jelly fishes add lo the Avonders of this submarine festival, and oval forms of red, blue, yellow, and green lints arc seen rising ami falling — veritable constellations of the sea ; while the waves, charged with disconnected masses, break and roll away, lighting up the darkness with a ghastly glare that is reflected by. the masts, sails, and rigging, that cast strange shadows over the deck and sea. The office of this strange light is rneio speculation, as somo fishes show the same, and many forms from great depths of the ocean. It has been surmised that its purpose is to provide light for those regions never to be explored and of utter darkness.