microscopic observation?

Are we not

driven by the scientists themselves into a belief in some vital principle which is not mere chemical action?

These creatures perform all the essential functions of life without a single organ. The mass of animal jelly takes in food without a mouth, digests it without a stomach, and rejects such portions as it cannot assimilate without an alimentary canal. It inhales the sea water, extracts from it the lifesustaining oxygen, and exhales it loaded with carbonic acid, the product of animal combustion, without lungs, blood-vessels, or pectoral muscles. It possesses the power of motion, sensation, and reproduction without muscles, nerves, or generative organs. Where, then, does the vital principle reside?

Throughout the animal kingdom there is an infinite variety of forms; but, whether the organism be high or low, sarcode is invariably present. As we descend the scale of being, the organs and systems apparently essential to life become simpler and fewer. The organs of perception and sense are obliterated; the systems-nervous, muscular, sanguineous, osseous-one after another disappear, till, in the lowest forms of existence, the monera, the amoeba, and the sponge animal, they are all wanting. But, from the highest to the lowest, sarcode is invariably associated with animal vitality. It lines the mouth, stomach, and alimentary canal of the highest forms of life; it composes the entire entity of the lowest. Under high microscopic powers, the mucous lining of the human digestive system presents an appearance similar to the sarcode of the protozoa. The only function essential to life is the power to convert nutriment into animal tissue; it is more than possible that this transmuting power resides in the mucous substance existing in every organic creature, and that in this substance the wondrous alchemy of life is wrought. However this may be (and it is only an hypothesis as yet), these animals possess this transmuting power, and they are simply masses of mucous matter without a single permanent organ.

A spoonful of the sarcode may be dipped from the living animal and deposited in a spot favorable to its growth. It is apparently unconscious of its involuntary secession, and certainly indifferent to it; soon it begins secreting a skeleton of its own, improvising a mouth wherever the food happens to be presented; in fact, showing that it is quite equal to supporting an establish

ment of its own. One very curious fact is, that while the whole sponge-mass shows a sensitiveness to disturbing causes, the living substance in which its life resides appears quite indifferent to any rending, or dissection, to which it may be subjected. Its life is social rather than individual. An instance is mentioned in which a parasite of the spongilla was observed passing rapidly over the surface of the sarcode, biting out pieces, here and there, without seeming in any way to incommode the sponge, or to interfere with the general action of its internal organs.

The possibility of life in the deep sea had not only been questioned by naturalists; it

square miles of sea bottom was forthwith consigned to desolation and death. When, however, it was found by direct investigation that life did exist there, the question became-how?

It is a noticeable fact, that, in the profounder depths of the ocean, live only those creatures which possess the power of taking in their food, by absorption through the exposed surfaces of their bodies. The carbonate of lime, silica, and keratose, out of which the sponges erect their skeletons, are known to exist, in solution, in the waters of the sea; organic matter has also been discovered in every sample submitted to chemical analysis. The suggestion, made in 1869 by Dr. Wyville Thomson, has been fully confirmed by experiment, and the water exhaled by the sponges is found to be deprived of the organic matter with which it was charged before being inhaled.

One peculiarity of the glass sponges is the wonderful variety and exquisite beauty of the spicules, or needles of silica, which penetrate the sarcode and bind it together. The usual type is hexradiate, which may be roughly described as three glass spines crossing each other at right angles; thus, there are six rays springing from one central point, each ray at right angles to all those adjacent to it. Sometimes one of the six is rudimentary, and sometimes they do not mutually bisect; there is a variety, almost infinite, without departure from the characteristic type. One of these rays, which is the primal axis, may be short or long; at some point four secondary rays cross the central axis at right angles. Where a long filament is needed for strength in the weaving of the skeleton, or for anchoring the sponge in the mud, the primal axis is abnormally developed, and the cross arms are rudimentary; a slight bulge in the center of the filament, which contains four secondary branches of the central canal, maintains the permanence of the type.

Each spicule is most elaborately formed of concentric layers of glass and intervening films of sarcode with a central sarcodous axis. Every form which could help to bind together the soft gelatinous flesh is to be found: arrows with feathery stems; anchors fluked at both ends; long stalks surmounted at either end with a crown of drooping leaves; Neptune's trident; curved hooks; pins with heads, and swords with hilts; stars, and beautifully formed rosettes; and yet no confusion growing out of these multitudinous shapes. The usual hexradi

ate type prevails, and forms upon the surface of the sarcode a delicate, reticulated, starry net-work of glass. The type is wonderfully flexile in its power of adaptation; the long glass hair by which the sponges anchor; the delicate filaments out of which the fabric of one is woven; the exquisite filmy veil which hides, while it discloses, the beauty of another, are all modifications of this characteristic type.

As early as 1835, the distinguished naturalist Von Siebold brought from Japan some curious wisps of glass hair measuring about twelve inches in length. Similar specimens were subsequently sold as sea-weed by the Japanese curiosity-mongers to European tourists and seamen. Not a fortnight ago, I saw, in one of the largest museums in our country, a specimen so labeled. One end of these wisps was usually inclosed in a leathery sheathing, and stuck into a piece of coral. Japanese ingenuity lends itself so freely to the concoction of impossible monsters, that anything strange, in the way of a natural curiosity from that country, is regarded with distrust. Combinations so skillfully made as to defy detection, except at the hands of the comparative anatomist, have made naturalists wary.

The first Hyalonema Sieboldii was therefore placed by the great microscopist, Ehrenberg, among the specimens of Japanese art. The microscope, which discriminates so unerringly between the works of nature and those of art, did not hesitate to pronounce the glass coil, the investing polyp, and the coral base, all to be natural; but the combination was supposed (and truly supposed, as far as the coral base was concerned) to be artificial.

New specimens, less mutilated than this first one, were constantly added to the European museums, till finally Hyalonema was promoted from the cabinet of Japanese art to the Museum of Natural Curiosities. Still, the question as to its origin and nature remained doubtful; the artificial combinations in which it was generally found were very misleading. The investing leathery membrane was undoubtedly a polyp, the cupshaped body which inclosed the wisp was no less certainly a sponge; but the wisp itself remained an insoluble mystery.

The Hyalonema lusitanicum consists of a long wisp of coarse glass hair slightly twisted throughout its length. Encircling the upper portion of the coil is a cup-shaped sponge of a buff color; below this, for several inches, the coil is inclosed in an embossed leathery

being the oscular openings of the creature provided for the excurrent streams of water! All this time, while the angry war of words went on, Hyalonema stood on its head wait

PLATE VI. EUPLECTELLA SPECIOSA.

(By the courtesy of Dr. Christopher Johnston.) ing to be classified. Not one of all its angry champions knew enough to put it in its correct position. The conical mass had been, from the first, assumed as its base, out of which the spreading wisp of glass hair was

supposed to spring upward into the water. Finally, Professor Lovén, of Christiana, pointed out the fact, that the Hyalonema had been described in an inverted position. The first suggested that the glass coil was used for the purpose of anchoring the sponge in the mud, and, of course, formed its base. In 1868, Dr. Perceval Wright brought up a specimen of Hyalonema from a depth of 600 fathoms in Setubal Bay, off the coast of Portugal. This was, perhaps, the first exploit that could be dignified by the name of deep-sea sounding, which was successfully accomplished in the great ocean. At last the embargo was authoritatively declared to be removed from the great valleys and low-lying plains of the ocean's bed, and eager man hastened into the new country to take possession of it. Each new attempt at deep-sea exploration was crowned with fresh discoveries. New and beautiful glass sponges were added to the list, till our modest Hyalonema was quite cast into the shade.

The Holtenia, which was also dredged off the coast of Portugal, is in shape a symmetrical oval or sphere, with a cup-shaped depression in the top. The outer and inner walls of the sponge are formed of a starry silicious net-work. The spicules of which this net-work is made are five-rayed, the sixth ray being rudimentary. The primary axis penetrates the sarcode, while the cross arms spread themselves over the surface. producing a delicate stellate pattern. When living, the interstices of the lacy fabric are filled with a delicately fenestrated matter like white of egg, which is its flesh. This sarcode is forever moving, widening or narrowing the cavities and canals which penetrate it, and gliding over the spicules. A current of water, urged by the motion of the cilia, flows into the openings occurring over the surface, and passes, finally, out of the large osculum, or exhalent cavity, in the top. The upper third of the oval is covered with rigid hairs of the purest glass, which stand up like a frill about it, while the lower third sends down a perfect maze of delicate glassy filaments, softer and silkier, to the eye, than an infant's hair. These constitute the anchoring filaments which characterize the whole family of glass sponges, so far as they are now known.

The two, however, which bear off the palm for exquisite beauty are the Rossella velata and the Euplectella speciosa. [See Plates III. and VI.] The Rossella is not unlike the Holtenia. Its body is of a symmetrical oval form, composed of a beautiful net-work

The glass hair of which these sponges are woven is not transparent, as might be imagined; it is of a pure and lustrous white, giving, in certain lights, an opalescent play of color. The texture is like frost-work, phantom flowers, the finest and filmiest of the real Shetland lace, which is rarely seen in this country; it is so exquisitely delicate and lustrously white as to beggar description, and to make one turn disheartened away from

of glass spicules invested by the sarcode. The chief beauty of this sponge is due to an exquisitely delicate veil, which seems to envelop it in its filmy folds. This appearance is produced by a maze of spicules which stand out from the surface of the sponge at the distance of a centimeter. The primal axis of each spicule partially penetrates the sarcode, and the cross arms interlace to form the veil. From the lower portion of the body tufts of glistening glass hair curve gracefully downward, here and there terminating in a quadrate barb, the more securely to anchor the sponge in the shifting bottom mud. The Rossella looks much like a pine-apple, wanting its crowning tuft of leaves, and its core, woven of fine glass hair, and veiling its loveliness in misty films of delicate spun glass. The Euplectella is even more beautiful than any species yet mentioned. It is brought from the Philippine seas, and the first specimen was described and "figured" as early as 1841 by Richard Owen. This first specimen was called Euplectella aspergillum. [See Plates IV. and VII.] In 1858 the Euplectella cucumer was brought to England [See Plate V.], and later, the most exquisite of all, the Euplectella speciosa, made its entrée into scientific society, the acknowledged queen of the glass-sponges. [See Plate VI.] It is a graceful cornucopia, formed of a delicate lace of a square meshed texture. Every angle is softened and rounded in effect by the weaving and interweaving of other filaments. The meshes are so perfectly regular that graduated series run from top to bottom of the curved vase, making the number in every encircling row the same. There seems to be a regular web and woof to the texture; but, heightening and softening all this formal beauty, a curious little ruffle, standing at right angles to the surface of the vase, runs backward and forward, and round and round the cornucopia to its very lid. Through this delicate and wayward little frill the exquisite precision of the square meshes beneath is seen. The vase is covered with a fretted lid of closer texture than the body of the sponge, and around the smaller end is an embracing tuft of glass hair curving up on every side. VOL. XI.-4.

analogy. In all the world there is perhaps nothing so fairy-like as these wonderful fabrics built up by this formless, structureless life, in the darkness and stillness of the deep

sea waters.

66

The glass-sponges, it would be seen, are of a particularly hospitable disposition, for most of them possess some commensal or humble friend, who always lives with them, and eats at the same table. Commensals differ from parasites in this, that they eat with, and not upon, the creature with which they are associated. They seem, by some mutual understanding, to come to an agreement to "chum together." The investing, leathery membrane of Hyalonema is a colony of such commensals, and, within the vase of the Euplectella, live two little crabs, hopelessly held in their exquisite prison-house, for here they live and here they die without possibility of release. The constant currents of sea water, created by the ciliary movement of the sarcode, brings food to the "commensal" as well as to the sponge.

Of the 140,000,000 square miles which lie under the sea, that which has been fairly dredged may be measured by the square yard; and yet how rich has been the fruit of these few years of deep-sea exploration. Every haul of the dredge brings up strange forms of life; some of them are strange, be