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this separation takes place, however, it gans--the intestine, the blood-vessels, has often begun to reproduce its own and the nervous cord; and each of the young, and so we sometimes see a six young must develop a heart, a brain, large colony of hydras all connected and a pair of eyes. An odd result of together, like minute branching water their method of growth (the first one weed.
being formed, you will remember, not After all, you may say, it is not so behind the parent but between her last very wonderful that a simple animal two rings) is that the eldest' offspring like the hydra, which has no intestines, appropriates the tail of his mother, and scarcely any special organs what, while his five brothers and sisters ever, should be able to reproduce its have to find tails of their own. We lost parts, or to multiply itself by the are here tempted to indulge in a curisimple processes of growth and sub- ous speculation: this first born prosequent division. Well, then, let us duces its young in the same way itself take a more complex creature, and we was produced, and passes on its inherhave a remarkable example at hand ited tail to the next generation. The in a certain marine worm called myr- eldest born of that generation beianida fasciata. It is an inch or two queaths it to the next, and so on. What in length, tapering off gradually from becomes of that ancestral tail in the the head. The body is marked with course of years ? Does it at last wear numerous rings or joints, attached to out and drop off? Does the worm which are oar-like appendages, serve that bears it die after a time without ing not only as instruments of propul- leaving any children? Or is it possision but also as gills, or breathing or- ble that the process of entail has been gans. An intestine extends from the going on without interruption ever head in a direct course to the posterior. since the year one of the world, and Blood-vessels are arranged about it that there may be a myrianida fasciata like a net-work, and connect with sim- now living with a tail as old as creailar vessels in the gills. It has an or- tion ? Not very probable, certainly ; gan which serves the purpose of a but if any solution has been offered of heart, a nervous cord swollen at every the great tail problem, we do not hapjoint into knots or ganglions, and, in pen to have heard of it. the head, one principal ganglion, Professor Clark also tried various which may be considered as the brain. experiments upon the common flat Its reproductive organs are situated worm, or planaria, which may be only in the posterior rings, and are found so readily in our ponds, creeplocated there in reference to the pecul- ing over stones and aquatic plants, iar mode of generation which we are and is so easily recognized by its opaabout to describe. The young worm que white color, and the liver-colored begins to grow immediately in front ramifications of its intestine. He cut of the parent's tail, that is to say, be the creature in two, and immediately tween the last joint or ring and the after the operation the halves crawled next before the last, and is formed by away as if nothing had happened ; the the successive growth of new rings. anterior part preceding an ideal tail, Before it is old enough to be cast off and the posterior one. following an another appears between its anterior equally imaginary head and brain. end and the next joint of the old stock; He watched the pieces from day to and so on until we have six worms at day, and found that each reproduced once, all strung together behind the its missing half by a slow process of parent, and hanging, so to speak, from budding and growth. This planaria one another's tails. They drop off may be cut into several pieces, and separately, in the order of their age. each will reproduce what is requisite Now in this case, you will observe, to complete the mangled organism. there must be a division of several or. If the tail of a lizard be broken off, a new one will grow; and crabs, lob- as to defy detection. Some of the insters, spiders, etc., are known to re- fusoria are no larger than the twentyplace their amputated limbs. The four-thousandth of an inch in diameinstances we now and then meet with ter, and it is estimated that a drop of of what are called monsters-two- water might contain five hundred milheaded dogs, calves with six legs, and, lions of them. It is obvious that the more rarely, even double-headed hu- germs of such little creatures must be man beings, are examples of the phe- invisible even with the best micronomenon of budding-which is very scope. The problem can only be common, by the way, among fishes; solved by placing a portion of the and there is an animalcule called the decomposing matter under such condiamaba which shows a more remarka- tions that any germs it may contain ble tenacity of life than any of the shall infallibly be killed and that none other creatures we have mentioned, can possibly reach it; then, if infusosince you may divide and subdivide it ria appear, we shall know that they until it is physically impossible to re- have been generated spontaneously, duce it to particles any smaller, The great difficulty is in securing and yet each piece will live.
these conditions. For the develop
ment of the living forms we require The discovery that animals may both water and air. How are we to originate in so many ways indepen- be certain that there are no living dent of maternal gestation naturally germs in the organic matter before we suggests the inquiry whether further begin the experiment? that there are researches may not develop still none in the water? that none are other methods of reproduction, in brought by the air ? The action of which the new-born creature shall heat has been relied upon for the dehave no connection whatever with any struction of germs in the organic matpreviously existing individual. Thus ter and the water, and it has been we are brought back to the question sought to purify the air from them by which was thought to have been set- passing it through sulphuric acid; tled long ago, whether generation ever but experience has shown that sultakes place spontaneously, as Aris- phuric acid does not kill the germs; totle and the old physicists supposed so of course experiments performed in it did. Later naturalists, following the that way prove nothing. Professor Italian, Redi, utterly rejected the sup- Clark quotes a series of very delicate position; but within the present centu- experiments tried by Professor Jeff ry it has found many reputable suppor- ries Wyman, of Harvard University, ters, and Professor Clark is one of them, which seem to us to come nearer to When organic matter decays, numbers proving spontaneous generation than of infusoria, or microscopic plants any others with which we are acand animals, arise in it. Where do quainted. He proceeded in three they come from? Do the disorgan- different methods, as follows: ized particles, set free by the process 1. The organic matter, consisting of decomposition, combine into new of a solution of beef or mutton juice forms, which are then endowed with (or, in a few instances, vegetable matlife by the direct action of Almighty ter), was placed in a flask fitted with power; or is the decaying substance a cork through which passed a glass merely the nest in which minute eggs tube. The cork was pushed deeply into or seeds, borne thither upon the air, the mouth of the flask, and the space or dropped by insects, find conditions above it was filled with an adhesive suitable for their development in the cement, composed of resin, wax, and ordinary natural way? The question varnish. The tube was drawn to a is not easily answered. Many of narrow neck a little way above the these germs are so excessively minute cork, and bent at right angles, and
the end of it inserted in an iron tube, a few days living infusoria were where it was secured by a cement of found in two instances out of four. plaster of Paris. The rest of the Now these experiments undoubtediron tube was filled with wires, leav- ly prove that generation sometimes ing only very narrow passages be- occurs spontaneously, provided it be tween them. The solution in the true, as Professor Clark assumes, flask was then boiled-in some cases that there was no imperfection in the as long as two hours—in order to closing of the flasks (which we see no kill any germs which might be en- reason to doubt), and that the infusoclosed, and to expel the air. The rial germs are destroyed by boiling. We iron tube and wires at the same time confess that it is hard to believe they were heated to redness. When the could have survived such a heat as boiling bad continued long enough was applied to them in these cases; the heat was withdrawn from beneath but is it certain that they could not? the flask, and the steam was allowed A writer in an English review a few slowly to condense. As it did so, air years ago, whom we believe to have flowed in between the red-hot wires, been Mr. G. H. Lewes, announced that which had been kept at a temperature he had boiled certain germs an hour and high enough, it was supposed, to de- three-quarters, and yet they remained stroy any germs in the air that pass- perfeotly unaltered. At most, thereed through them. The flask was fore, we can regard spontaneous then hermetically sealed by fusing generation as a probable phenomenon. the glass tube with the blow-pipe. Whether spontaneous generation, When opened, several days afterward, if it occurs at all, occurs by the forit was found to contain animal life. mation of an egg from which the ani
2. A similar solution was placed in malcule is hatched, or by the immea flask the neck of which, instead of diate formation of the adult, Profesbeing supplied with a cork and tube, sor Clark does not attempt to say ; was drawn out and bent at right an- but the French naturalist M. Pouchet, gles, and then fitted to the iron tube who is one of the foremost advocates containing wires. The experiment of the theory, holds that an egg is was performed as by method No. 1, produced first. If this is true we and with the same result.
shall have a striking correlative to 3. That there might be no suspi- the proposition with which we began cion of imperfectly sealed joints, a so- this paper : not only can living crealution was put into a flask with a nar- tures be developed where no egg has row neck, and the neck itself was been deposited, but eggs can be prothen closed by fusing the glass. The duced where there is no animal to lay whole flask was then immersed in them. Omne ovum e vivo will be no boiling water. At the expiration of more true than Omne vivum ex ovo.
From Chambers's Journal.
POOR AND RICH.
In a shattered old garret scarce roofed from the sky,
But the cracked plastered walls are emblazoned and bright
Though my children's soft voices no music now lend ;
So, though fetid the air of my poor room may be,
From The Lamp.
ALL-HALLOW EVE; OR, THE TEST OF FUTURITY.
BY ROBERT CURTIS.
mon as he is, he could not murder you.
Heaven would not permit so much WHILE the above exploits were be wickedness!” ing performed by Jamesy Doyle and Emon looked at her again. A faint the police, a sad scene indeed was be- but beautiful smile-beautiful now, for ing enacted at the bridge. Winny the color had returned to his cheeks Cavana, whose bonds had been loosed, -beamed upon his lips as he shook had rushed to where Emon lay with his head. his head in his father's lap, while the “Yes, yes, he has murdered him," two policemen, Cotter and Donovan, sobbed the distracted father; "and I moved up with their prisoner. They pity you, Winny Cavana, as I hope not only handcuffed him, but had tied you will pity his poor mother; to say his legs together, and threw him on the nothing of myself.” side of the road, “ to wait their conve- “ No, no, do not say so! He will nience," while they rendered any as- not die, he shall not die!” And she sistance they could to the wounded pressed her burning lips to his marble
forehead. It was smooth as alabaster, The father had succeeded in stanch cold as ice. ing the blood, which at first had poured “Winny Ca-va-na, good-by," freely from the wound. With the as- he faintly breathed in her ear. “My sistance of one of the police, while the days, my hours, my very moments are other was tying the prisoner, he had numbered. I feel death trembling in drawn his son up into a sitting posture every vein, in every nerve. I could and leaned him against the bank at could-have-lived for you— Winny; the side of the road, and got his arm but even-to-die for you-is-a blessround him to sustain him. He was ing, because-successful. One last not shot dead; but was evidently very request-Winny, my best beloved, is badly wounded. He was now, however, -all-I have-to ask; spare mea recovering strength and consciousness, spot in Rathcash-chapel-yard, in the as the blood ceased to flow.
space allotted to-the-Cavanas. I "Open your eyes, Emon dear, if feel some wonderful strength given me you are not dead, and look at your just now. It is a special mercy that I own Winny," she said; “ your mad may speak with you before I go. But, Winny Cavana, who brought you Winny, my own precious, dearest love, here to be murdered! Open your do not deceive yourself. If I reach eyes, Emon, if you are not dead! I home to receive my mother's blessing don't ask you to speak.”
before I die, it is the most" and he Emon not only opened his eyes, but leaned his head against his father's turned his face and looked upon her. breast. Oh, the ghastly smile he tried to hide! “No more delay !” cried Winny en
"Don't speak, Emon; but tell me ergetically, “Time is too precious to with your eyes that you are not dying. be lost; bring the cart here, and let us No, no, Emon-Emon-a-knock! de- take him home at once, and send for
VOL. III. 16