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seems to hesitate on the point, add. mark of species. Thus, to select ing, “ but it is asserted by numerous a striking example, Mr. Gosse makes authorities that the young are not two distinct species of the orangeunfrequently born alive. I not only disked and orange-tentacled anemoassert this, but ask whether any nes, naining them Venusta and one has ever seen the contrary. It Aurora; but as if to prove the indifstartled me, however, when, on open- ference of all such characteristics, I ing an anemone, I for the first time brought with me from Tenby an baw a young one drop out, and im- orange-disked—and only one—which, mediately expand its tentacles; and before it had been honne a fortnight, some days afterwards, as I was carry- I discovered, with great surprise, was ing home a lovely “gem,” I saw first changed into an orange-tentacledone, then two, three, four, seven young disc and tentacles being of a rich ones issue from its mouth, fix them- orange hue, the only traces of white selves at the bottom of the vase, and remaining just at the tips. If there make themselves at home; they were had been any other specimen in the of various sizes, and in various stages vaso I might have doubted ; but of development. Since then, I bave having only one in company with repeatedly witnessed this mode of a white daisy, and a smooth anebirth : and one day, seeing something mone, there was no avoiding the in the inside of the tentacle of a Daisy, conclusion. I snipped the tentacle off, and found The reader was promised “New a young daisy there. Some writers Facts,” and those already furnished imagine that the young issue through will show him how great an accesthe orifices at the tips of the tentaclession to our knowledge may be antici-2 supposition not very credible. pated from the present direction of The truth is, that at the bottoin of so many minds towards these anithe stomach there is a large opening mals; what is written in the best —not several minute openings as books must be accepted as only
see figured in books-through suggestions of a few observers, to be which the young pass from the controlled by the investigations of general cavity into the water; and succeeding observers. Many probthis appears to me the only exit lems await solution; many stereofor the young
Without absolutely typed assertions must be disproved. denying that the ova are extruded, Let us here consider one or two and their early development carried accepted “facts” which will turn out on out of the parent's body, I have to be “ fancies" when rigorously never been able to detect ova, except examined. within the parent. The most curious Perhaps nothing has excited more of all my observations on this point surprise on the part of the public, was the finding in the visceral cavity and nothing has been more unaniof a smooth anemono a young one as mously believed by anatomists, than large as a cherry; and to complete the hypothesis that certain minute the marvel, it was faintly striped with organs found in Polypes, and varigreen, like the well-known
green- ously styled thread capsules, filiferstriped variety," although its parent ous capsules, or urticating cells, are was of a dark-brown hue. Could organs of urtication, or stinging. the old one have swallowed an errant The uncritical laxity with which youth by mistake ? No. It had this hypothesis has been accepted been many weeks in captivity, where may point a lesson. I do not allude no such errant youths were within to the acceptanco of the fact that reach : besides, anemones do not certain capsules containing threads swallow each other ; cannibalism be- are found in Polypes, but to the aclongs to a higher grade of develop- ceptance of the alleged purpose or ment. Apropos of this peculiarity of function of these capsules. The colonr, I may remark on the great things are there, sure enough ; but variations observable in the colour of whether they serve the urticating anemones, and the impropriety of purpose is another matter. Ever making colour the distinguishing since they were first described by
Wagner,* Erd!,t Quatrefages, and with which some of them seem to be Siebold, f they have passed without furnished, will at once admit that challenge. They have been detected the hypothesis of the “nettling" or in the whole group of Polypes, in “urtication” being performed by Jelly-fishes, in the papillze of Eolids, these threads is an hypothesis so and, according to Vander Hoeven, in obvious, an explanation so natural, Planariæ; yet, as far as my reading that-it should be doubted. In all extends, not one single experiment complex matters, we should mistrust has been made to prove the function the obvious explanation; I do not so unanimously admitted, not a single say that we should disregard or reject test has been applied to strengthen it, but mistrust it. When we know, or controvert what was, indeed, very on the one hand, that the jelly-fish plausible, but only plausible, not stings, and when, on the other hand, proren. Accordingly, no sooner did we know that it is furnished with I submit the question to that rigor- numerous cells, in which are coiled ous verification which science impe- threads, to be seen darting out when riously requires, than it became clear pressed, the idea of connecting the to me that my illustrious predecessors stinging with these threads is inevi--Wagner, Erdl, Siebold, Quatre- table: but this is not enough for fages, Ehrenberg, Agassiz, and Owen science; it is only a preparatory -men whom the most presumptuous guess, which proves nothing; it may would be slow to contradict, had ad- be right, it may be wrong. I believe mitted the point without proof, be- it is altogether wrong. We have cause it wore so plausible an air. already seen how erroneous was the Let me hope the reader will accuse supposition that Polypes paralysed me of no immodesty in thus contro- their victims with a touch; that verting men so eminent; he will see poison was secreted by their tentacles; that whereas they have only hypo- yet for this supposition there was at thesis on their side, I have the ac- least the evidence of partial observacumulated and overwhelming weight tion, whereas, for the supposition we of esperimental evidence.
have now to consider, there is absoWhat are these 66 capsules," or lutely no evidence at all. "urticating cells?” The uninstructed On a survey of the place where reader may be told that the Polypes these “urticating cells" are present, are supposed to urticate, or sting, we stumble upon an unlucky fact, liko nettles; and the nettling or- and one in itself enough to excite gans, or urticating cells, are sup- suspicion. They are present in a few posed to be minnte suboval micro- jelly-fish—which urticate; in actinia scopic capsules, quite transparent, —which urticate; and in all polypes containing within them threads —which, if they do not urticate, are coiled up, which, on pressure, dart popularly supposed to do so, and at ont to many times the length of any rate possess some peculiar power the capsule, into which they never of adhesion. In all these cases return. This thread Agassiz likens organ and function may be said to a lasso thrown by the polype to to go together. But the cells aro secure its prey. I will not enter here also present in the majority of into minute details of structure, jelly-fish, which do not urticate; which would only confuse the reader, in Eolids—which do not urticate; who, if curious, will find all that is and in Plana ia—which do not known, in the works of Mr Gosse, urticate. Here, then, we have the and the treatises of Owen, Siebold, organ without any corresponding and Rymer Jones. Any one who has function; urticating cells, but no uronce seen these threads under the tication. The cautious mind of Owen microscope darting out with light- had already warned us that there ning rapidity, especially if he uses a was something not quite satisfactory high power, and detects the hooks in our supposition; some super
WIEGMANN's Archiv., 1835, ii. p. 215. + Muller's Archiv., 1841, p. 423.
Comp. Anat., i. p. 39 (English Trans.)
addition to the thread-cell would taneously on the slightest pressure ; seem to be essential to the urticating in point of fact it frequently cannot faculty," he says, when speaking of be pressed out at all, even when the the jelly-fish, “ since these cells are whole force of the finger is exerted present in species and parts that do on the two pieces of glass between not sting.” It is to be regretted that which it lies. From the very caprihe was not moved by this doubt to a cious way in which the threads dart closer examination of the evidence on out while under the microscope, and which the urticating faculty rested; not under pressure, and from the frohe would assuredly have been led to quent impossibility of pressing them the belief that no superaddition to out, I suspect that pressure has really the thread-cell will account for the nothing normally to do with the ejecphenomenon.
tion of the thread. But I waive the argument derived Ilitherto we have merely considered from such a source, and, confining facts of observation; we shall now inyself to the anemones, ask tho see them confirmed by experiment. reader what he thinks of this awk- Mír. Gosse proposes to establish a new ward fact, namely, that these urticat- genus, named Sagartia, on this purely ing cells are most abundant in parts hypothetical function; including in which do not urticate ? Only the ten- it all those anemones which, like the tacles have this power, and although Daisy and Dianthus, possess an abunthey have numerous cells, the urtica- dance of peculiar white filaments, tion cannot well bo attributed to them, visible to the naked eye, which are since these cells are more abundant protruded from the pores of the body in the convoluted bands, in the lining and the mouth, when the animal is walls of the stomach, and in the blue roughly handled. These filaments spots which surround the oral disc in are seen, on examination, to be chiefly the smooth anemone—these spots, composed of the “urticating cells." indeed, being made up of such cells Mr. Gosse names the genus Sagartia, and small granules-yet in not one because Herodotus says of the Sagarof these parts can the slightest urti- tians, that “when they engage with cation be traced! How is this? If the enemy they throw out ropes these cells are the nettling organs, which have nooses at the end, and why do they not nettle in those parts whatever any one catches he drags where they are most abundant? No towards himself, and they that are one has thought of asking this ques- entangled in the coils are put to tion.
death." The name, you perceive, is It thus appears that animals hav- aptly chosen, that is, it would be, if ing the cells, have none of the power the hypothesis of the filaments were attributed to the cells; and that even not a tigment. The filaments have no in those animals which have the such lasso-like and murderous power. power, it is only present in the ten- This Mr. Gosse would deny; and I retacles, where the cells are much less member he somewhere records an obabundant than in parts not manifest- servation which would perhaps quite ing the power: the conclusion, there- satisfy him that his denial has good fore, presses on us that the power ground to stand on. He relates that does not depend upon these cells. he once saw a small fish in the conAnd this conclusion is strengthened vulsions of agony, with one of these every step we take. Thus the Anthea filaments in his mouth; it shortly is of all anemones the most pov.er- expired, and he unhesitatingly confully urticating; yet if we compare its cludes from this fact that the Sagarcells with those of other anemones, tia “ will attack even vertebrate we find them greatly inferior in animals." It is a matter of surprise quantity to those of the Daisy and and regret that Mr. Gosse, having once Dianthus, and much inferior in size made such an observation, did not feel to those of Crassicornis, as well as the imperative necessity of repeating less easily made to recoil their and varying the fact, so as to be sure threads. It has not been remarked, that the death was not a mere coincithat.whereas according to theory the dence. If the filament had the power thread should dart out almost instan- which this single observation fairly seemed to snggest, nothing could be contrary aspect, namely, the blunt easier than to establish the fact by ex- end of the cell being in contact with periment. But, I repeat, no one has the animal, the hook and thread seen the necessity for the verification being turned towards the polype. of an hypothesis so plausible; and I have reserved one fact as the coupMr. Gosse, like all his predecessors, de-grace. Having shown that the was content with recording his obser- parts most abundantly supplied with vation, as if it carried the point. Not these “urticating cells” do not urtibeing so content, I tested it thus: cate, I can now remove the last vestige After irritating & dianthus till it of doubt by the fact that the cell sent out a great many filaments, I itself from the tentacle of an anemone, dropped a very tiny annelid among when seen to eject the thread and them, and entangled it completely in touch an animalcule, does not kill or their meshes. Yet lo! these fila- disable that animalcule; a fact I ments, which are said to possess so witnessed when examining the cells powerful a faculty of urtication that under the microscope. This not only even vertebrate animals are killed by gives the coup-de-grace to the general then, had no other effect upon a soft hypothesis, but even sets aside that annelid than that' of detaining it in suggestion of Professor Owen's retheir meshes, from which it short- specting the probable superaddition ly freed itself and wriggled away to the urticating cell which is to disanhurt. Nor was I yet satisfied ; tinguish it from cells in those parts placing a tiny crustacean, of the destitute of the power. shrinp family, among the filaments The foregoing discussion has had of another dianthus, I saw it remain a purpose beyond that of rectifying there enveloped, but apparently quite an universal error—the purpose of comfortable, not in the least so desir- pointing a lesson in comparative anaous of escaping as one would expect tomy. The greatest living experiif it were being. “ nettled” all over; mental physiologist, Claude Bernard, and when I lurched the jar it swam has recently insisted with emphasis away. I have since repeated this on the importance of recognizing esperiment with entomostraca and “anatomical de:luction” to be a annelids without once detecting the fruitful source of error.* He warns slightest indication of their being us against attempting to deduce a more incommoded by the filaments function from mere inspection of the than they would have been by threads organ, without seeing that organ in of silk. Mr. Gosse, indeed, not only operation, and applying to it the test maintains that these filaments are of experiment. As a case of pure Weapons of offence, but he actually deduction, this hypothesis of the gots so far as to suggest that the urticating cells” seemed to comblue spherules which surround the mand, and did cominand, instantadisc of the Mesembryanthemum may neous assent; but on submitting it " represent the function of these mis- to verification, we find the hypothesis sile filaments” because they are com- to be an error. To the philosophical posed of the thread capsules. But I mind, therefore, there will have been repeat, the hypothesis which assigns an interest in the foregoing discussion to the thread capsules a function of greater than any interest issuing out artication or prehension, is an hypo- of the mere conclusion respecting the thesis without a single fact to war- thread-capsules. rant it, and is contradicted by the There are other new facts which various facts I have just adduced. were yielded to patient investigation, Ehrenberg has very unwarrantably but, having limits necessarily somegiven an ideal figure of a hydra in what circumscribed, this Magazine the act of seizing its prey, with the cannot contain all facts, even were hooks of the thread-cell extended; but, its readers of unappeasable appetite; as Siebold truly remarks, the animal so I will confine myself to the single is nerer seen thus; and I will add discovery of the reproductive system that it is always seen in precisely the in the anemones, that being of some
importance in itself, and helping to of a series of investigations. That illustrate the need there is for rigor- the reader may follow clearly the ous scepticism and extended obser- course of reasoning presently to be vation, on the part of zoological stu- traced, it is necessary to begin with dents.' So long as we unsuspectingly a few explanations which the better accept what is repeated in books, instructed will pardon. Let us first without being assured that the state- fix in our minds a definite idea of the ments are made on suflicient evidence, structure of the anemone, as far as and so long as we have eyes but ob- it will be involved in the subsequent serve not, zoological progress will remarks. Imagine a glove expanded necessarily be slow, in spite of the into a perfect cylinder by air, the vast number of excellent observers thumb being removed, and the fingers and workers who do accelerate our encircling, in two or three rows, the progress by genuine work. When I summit of the cylinder, while at the insist on the necessity for circum- base the glove is closed by a flat surspect doubt, and verified observation, face of leather. If now on that disc the reader must not understand me which lies within the circle of fingers as implying that this necessity is not we press the head of a pencil-case, vividly present to the mind of many and so force the elastic leather to zoologists, and of every real worker; fold inwards, and form a sort of sac for in truth, only by such methods suspended in the cylinder, we have can any solid result be reached, and by this means made a mouth and no one even superficially acquainted stomach; we then cut a small hole with the present state of zoology will at the bottom of the sac, and thus be disposed to underrate the import- make a free communication with the ance and extent of that band of dis- general cavity. We then divide thi.; tinguished investigators whose re- general cavity by numerous partisearches daily unfold fresh discov- tions of card attached to the wall of eries. Not, therefore, as throwing the cavity, and form a number of sepaany shadow of scorn on these men rate chambers called the interseptal and their methods ; nor as if I were spaces. Just as the cavity of the bringing a neglected principle into finger is continuous with the cavity prominence, am I tempted to insist of the glove, so are the cavities of the on the only method of successful pur- tentacles continuous with the intersuit in these studies; but simply to septal spaces. In these spaces will distinguish by it the students of zo- be found long coils of delicate memology who wish to increase the circle brane, which are sometimes seen of knowledge by some small addition lolling out of the mouth, and always of new fact, from students who wish bulge out when the aneinone is cut merely to ascertain what is known. open ; these are called the convoluted In zoology, as in all other depart- bands, and to them attention is parments of intellectual, activity, there ticularly directed. If the reader will are men contented with “informa- now look at the diagram in Mr. Tugtion," whose ambition never passes well's Manual (Plate II., fig. 4), in beyond erudition.
They want to Rymer Jones, or indeed in any know what is known. Others there modern work on zoophytes (wrong as are who, less solicitous, it may be, these diagrams are in several details) about what is known, are intensely he will have a tolerably accurate conmoved to know for themselves; and ception of the general structure of an these are the workers who extend Actinia. the circle of the known.
Certain general facts must now be What is known of the reproduc- borne in mind. First, let me call tive system of anemones? Not attention to the fact that in all ani. much, and that little confusedly. mals, the highest as the lowest, the The text-books are somewhat pre- envelope is of eminent importance, its cise; but the precision is for the most predominance bearing a procise ratio part that of error. I carried with to the simplicity of the organism. me to the coast this amount of de- The simplest organisms breathe, exfinite error, which gradually re- hale, secrete, absorb, and reproduce vealed itself as error in the course by their envelopes alone; and if the