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NEW FACTS AND OLD FANCIES ABOUT SEA ANEMONES.
SINCE the British mind was all sioned this sudden enthusiasm for alive and trembling with that zoolo- anemones ; lovely, indeed, but by no gical fervour which the appearance of means the most lovely, and certainly the hippopotamus in Regent's Park not the most interesting wonders of excited for many months, no animal the deep. Mr Gosse by his pleasant has touched it to such fine issues books, and Mr Mitchell by his tanks and such exuberant enthusiasm as in the Regent's Park Zoological the lovely sea-anemone, now the or- Gardens, have mainly contributed to nament of countless drawing-rooms, the diffusion of the enthusiasm ; and studies, and back parlours, and the now that enterprise has made a delight of unnumbered amateurs. commercial branch of it, we may In glass-tanks, and elegant vases of consider the taste established, for at various device, in finger-glasses, and least some years. One good result of common tumblers, the lovely creature this diffusion will be an extension of may be seen expanding its coronal of our knowledge, not only of this, tentacles, on mimic rocks, amid mimic but of many other of the simpler forests of algæ, in mimic oceans of animals. For many years the writpump-water and certain mixtures of ings of zoologists have given a place chlorides and carbonates, regulated to observations on the anemones; by a “specific gravity test." Fairy but the observations have been infingers minister to its wants, remov- complete, and all hand-books and ing dirt and slime from its body, treatises which repeat these observafeeding it with bits of limpet or raw tions are, very naturally, crowded beef; fingers, not of fairies, pull it with errors. To give the reader an about with the remorseless curiosity of idea of the state of current opinion science, and experiment on it, accord- on this one topic, it is enough to ing to the suggestion of the moment. mention that on the second page At once pet, ornament, and “sub- devoted by Professor Rymer Jones * ject for dissection,” the sea aneinone to a description of the habits of the has a well-established popularity in anemone, there are six distinct erthe British family circle ; having the rors : yet this is no fault of his ; he advantage over the hippopotamus of states what all preceding writers being somewhat less expensive, and state, and his excellent summary of less troublesome, to keep. Were sea- what is known bears the date of Cows as plentiful as anemones, one 1855. If the habits have been so could not make pets of them with imperfectly observed, you may guess the same comfort. There would be what a chaos the anatomy and objections to Potty in the drawing- physiology of this animal present. room. There would be embarrass- Such being the state of the case, we ments in the commissariat. There may hope that the wide diffusion of a would be insurgents among the taste for vivaria will in a little while domestics ; for the best tempered furnish Science with ample material ; Betty might find it impossible to and meanwhile, as many of Maga's stand” the presence of such a pet, loving readers are possessors of and resolutely refuse to bring up his vivaria, actual or potential, and will water, and clean out his crib; where- certainly not content themselves with as, although the red - armed Betty blank wonderment, but will do their thinks you a little cracked when you utmost to rightly understand the introduce “them worm things ” into anemones, even if they make no your house, she keeps her opinions wider incursions on the domains of within the circle of the kitchen, and the zoologist, I may hope they will consents to receive her wages with be interested if I group together the out a murmur.
results of investigations, pursued at It is difficult to say what occa- Ilfracombe and Tenby during last
* General Outline of the Animal Kingdom, p. 66.
summer, and, with less energy, fines of the animal and vegetable because with less prodigality of kingdoms, when all the while specimens, during the autumn and Nature knows of no such demarcatwinter at home. In the present ing lines. The Animal does not state of knowledge, the independent exist ; nor does the Vegetable: both observations of every one who has are abstractions, general terms, such had any experience cannot but be as Virtue, Goodness, Colour, used to welcome.
designate certain groups of partiIt must be assumed at starting culars, but having only a mental that the reader knows what a Sea existence. Who has been fortunate Anemone is, in aspect at least. No enough to see the Animal ? We description will avail, in default of have seen cows, cats, jackasses, and direct observation ; even pictures so camelopards; but the “rare monster” admirable as those in Mr Tugwell's Animal is visible in no menagerie. charming little book,* only give an If you are tempted to call this metaapproximate idea; while to those physical trifling, I beg you to read who have seen neither picture nor the discussions published on the animal it will be of little use to de- vegetable or animal nature of Diatoclare that the “Actinia is a fleshy maceæ, Volvocinæ, &c., or to attend cylinder, attached by one extremity to what is said in any text-book on to a rock, while the free end is sure the distinctions between animals and mounted by numerous tentacula vegetables, and you will then see arranged in several rows, which, there is something more than metawhen expanded, give the animal the physics in my paradox. In the appearance of a flower.” Assuming simpler organisms there is no mark then that you know the general which can absolutely distinguish the aspect of the Actinia, you may follow animal from the vegetable; and if my description of the animal's bear- in the higher organisms a greater ing and habits. How do I know that amount of characteristic differences it is an animal, and not a flower, may be traced, so that we may, for which it so much resembles? Well, purposes of convenience, consider to be perfectly candid, I do not a certain group of indications as know it. Nobody does. No one entitling the object to be classed yet has been able to distinguish, in under the Animal division, we must the face of severe critical preci. never forget that such classifications sion, between the animal and plant- are purely arbitrary, and as the organisation, so as to be able authori- philosophers say-subjective. tatively to say, “This is exclusively Now what are the characteristic animal.” To distinguish a cow from marks of the Sea Anemone, which a cucumber requires, indeed, no pro- entitle it to be removed from the found inauguration into biological hands of the botanist, and placed in mysteries; we can“venture fearlessly those of the zoologist Rymer Jones to assert" (with that utterly uncalled assures us, that its animal nature “is for temerity exhibited by bad writers soon rendered evident,” and he thinks in cases when no peril whatever is this evidence is the manifestation of hanging over the assertion) that the sensibility. “A cloud veiling the cow and cucumber are not allied - sun will cause their tentacles to fold no common parentage links them to as though apprehensive of danger gether, even through remote relation- from the passing shadows.” Unship; but to say what is an animal, happily, the fact alleged is a pure presupposes a knowledge of what fiction ; and, were it true, would not is essentially and exclusively ani- distinguish the Actiniæ from those mal; and this knowledge unhappily plants which close their petals when has never yet been reached. Much the sun goes down. A fiction, howhot, and not wise, discussion has ever, it is, as any one may verify. occupied the hours of philosophers in If Actiniæ have been seen to fold up trying to map out the distinct con- their tentacles when a cloud has
• A Manual of the Sea Anemones commonly found on the English Coast. By the Rev. GEORGE TUGWELL. 1856.
passed before the sun, this has been much in the same way as plants a coincidence, not a causal relation; assimilate the organic material difso far from light being the necessary fused through the soil and atmoscondition of their expansion, they are phere. Filter the water carefully, in perfect expansion in the darkness; and remove from it all growing vegeand if the venturous naturalist will tation, and you will find the animal imitate Mr Tugwell, and, with the fasting, but speedily dying, however solemn chimes of midnight as accom- freely oxygen may be supplied. It paniment, take his lantern on the is on this account that when we rocks, he will find all the Anemones make artificial sea-water, it is nein full blossom. Then again, al- cessary to allow algæ to grow in it though the Anemone entraps its prey, for some two or three weeks before or anything else that may come in putting in the animals; by which contact with its tentacles, this is no time the water has become chargeil proof of animality, for the sensitive with organic material. plant, known as the Flytrap of Venus Mere sensibility and capture of
Dioncea muscipula), has a precisely food, therefore, are not the distinanalogous power; any insect, touch- guishing marks we seek, since the ing the sensitive hairs on the surface plant is found to possess them as of its leaf, instantly causes the leaf to perfectly as the animal. Is spontashut up and enclose the insect, as in neous locomotion a sufficient mark? a trap ; nor is this all : a mucilagin- No; and for these two reasons : ous secretion acts like a gastric juice Some animals have no such power; on the captive, digests it, and ren some plants, and all spores, have it. ders it assimilable by the plant. There are animals which no botanist which thus feeds on the victim, as has ever claimed—the Ascidians, for the Actinia feeds on the annelid or example, which can scarcely be said crustacean it may entrap. Where, to exhibit any motion at all (the then, is the difference ? Neither seeks rhythmic contraction and expansion of its food : place the food within a their orifices not deserving the name), line's breadth of the tentacles, or while their whole lives are spent rootsensitive hairs, and so long as actual ed to the rock or shell, as firmly contact is avoided, the grasping of as the plant is rooted in the earth. the food will not take place. But Nay, even with regard to the aneyou object, perhaps, that this mode mones, it is said by Dr Landsof feeding is normal with the Actinia, borough, Dr Carpenter, and others, exceptional with the Flytrap. The that they will not move towards the plant, you say, is nourished by the water, should the vessel be gradually earth and air, the animal depends on emptied, or the water evaporate, not what it can secure. I must contra- even if their tentacles can reach its surdict you; indeed I must, although face. This is incorrect; but I menwith the profoundest respect. For tion it as one of the difficulties which granting-what, in fact, I sturdily would meet the student in the way of dispute that the Flytrap is in no distinguishing the anemone from way dependent upon such insect food plants. It is one of the many inacas may fall into its clutch, we shall curate statements, groundedon imperstill observe the Actinia in similar fect observation, which are repeated independence. Keep the water free in hand-books. The original obfrom all visible food, and the Actiniæ server probably noticed an anemone continue to flourish and propagate some time out of the water, making no just as if they daily clutched an un- effort to return ; had the observation happy worm. The fact is well been continued, the doubt would have known, and is currently, but errone- been solved. Some anemones, especiously, adduced as illustration of the ally the common smooth species (Meanimal's power of fasting. But there sembryanthemum) are accustomed is no fasting in the matter. In this daily to be left out of water by the water free from visible aliment there receding tide, so that in captivity they is abundance of invisible aliment, — may be supposed rather to enjoy an infusoria, spores, organic particles, occasional air-bath. I have repeatedly &c. which the animal assimilates, spon mine crawl out of the water
and settle on the edge of the glass not to say gourmandise ; in the mator pan, high and dry; but they de- ter of shell-fish it would put even scended again after a few hours. Dando to the blush. Dr Johnston The locomotion of the anemones is, in his valuable History of British however, various in various species. Zoophytes relates this anecdote I do not think the “Trogs" ever (which you are not bound to believe) : move ; nor do the “ Gems” seem “I had once brought to me a specimigratory ; but the “Antheas” and men of Actinia crassicornis that the “ Smooths" are somewhat rest might originally have been two inches less. “The Actiniæ,” says Rymer in diameter, and that had somehow Jones,“ possess the power of chang- contrived to swallow a valve of ing their position ; they often elon- Pecten maximus of the size of an gate their bodies, and, remaining ordinary saucer. The shell fixed fixed by the base, stretch from side within the stomach was so placed to side, as if seeking food at a dis- as to divide it completely into two tance ; they can even change their halves, so that the body stretched place by gliding upon the disc that tensely over had become thin and supports them, or detaching them- flattened like a pancake. All comselves entirely, and swelling them- munication between the inferior porselves with water, they become nearly tion of the stomach and the mouth of the same specific gravity as the was of course prevented ; yet instead element they inhabit, and the least of emaciating and dying of an agitation is sufficient to drive them atrophy, the animal had availed itelsewhere. Reaumur even asserts, self of what had undoubtedly been that they can turn themselves so as a very untoward accident, to increase to use their tentacles as feet, crawl- its enjoyments and its chance of ing upon the bottom of the sea ; but double fare. A new mouth furnished this mode of progression has not been with two rows of numerous tentacles observed by subsequent naturalists." was opened upon what had been the Yes, Dr Johnston once saw it ; I also base, and led to the under stomachwitnessed an Anthea moving thus; the individual had become a sort of but I suspect it is only the Anthea Siamese Twin, but with greater intiwhich has the power, and this it macy and extent in its unions,” probably owes to its more solid ten- Such is the blind voracity of this tacles.
animal, that anything and everyAgain the question recurs, How thing is carried straightway into then do we know the anemone to be its stomach to be there tried, and rean animal ? in other words, what jected only on proved indigestibility. characteristic marks guide zoologists One day, while sorting and distriin classing it in that division ? I buting to their respective jars the really know of none but purely ana- animals captured during the morntomical marks.* These however, suf- ing's hunt, I was called into the balfice, and if you please we will con- cony by the agitated entreaties of tinue to speak of the anemone as an lovely Sixteen, exelaiming, “Oh, do animal, and, what is more, a very car- come, Mr Contributor! do come, and nivorous animal, eating most things rescue this green anemone from a that come within reach, from limpets great nasty beetle.” I went to the to worms, from fish to roast beef. rescue, and found a large beetle It has even a reputation for voracity, struggling in the clutches of a green
* It is unnecessary to particularise these anatomical marks, which will occur to the mind of every student, as belonging exclusively to tbat division of animated beings which manifest the group of phenomena baptised by the name of Animality. Wherever you find muscular tissue, or an alimentary canal, you are absolutely certain that nothing belonging to the vegetable kingdom is before you. In function there is often considerable resemblance between Plant and Animal; but in structure the differences early manifest themselves, growing greater as the scale ascends. Although, therefore, at the bottom of the scale no distinguished characteristic isolates animals from plants, as we ascend the scale we find many definite marks by which the two groups may be known.
Anthea not much larger than him- thing approaching to stinging ; but self. “The beetle is the victim," I I never touched a tentaculum withquietly told Sixteen, who, not having out perceiving the tip of it had some profound sympathies with beetles, prehensile property by which it took was pacified as she saw the struggling a slight hold of the skin of the finger, insect slowly passing into the stomach causing a kind of rasping feeling when of the Anthea, his struggles growing withdrawn. It may be, however, that fainter and fainter, and finally ceas- the fangs had not fair play with my ing altogether, till at last we saw fingers, if somehow or other they are him with head and thorax engulfed sting-proof.”* He then makes the in the ravenous maw, his abdomen following quotation from Mrs Pratt's sticking up in the air.
Chapters on the Common Things of A question of great interest and the Sea-side, which I reproduce as some intricacy here presents itself : positive and direct testimony: “It Was the beetle paralysed by some appears that different persons are peculiar poison secreted from the ten- variously affected even by touching tacles of the anemone fa question the same Actiniæ. The author had which opens into this wider one: placed in a vessel of sea-water a fine Have the polypes the mysterious specimen of the fig marygold seapower, almost universally attributed anemone, which she was accustomed to them, of paralysing with a touch to touch many times during the day. the victims they may grasp, so that, The tentacula closed immediately should the victim escape from the round the intruding finger, producgrasp, it is only to die presently from ing only a slight tingling. Her surthe fatal touch? The powers of fas- prise was great at finding that the cination possessed by some animals, same anemone, on being touched by of poisoning possessed by others, of another person, communicated a more electrical discharges possessed by powerful sensation, which her friend others, naturally lead men to in- assured her was felt up the whole of terpret certain observations made on the arm. More than twenty persons the polypes, as proofs that they, too, touched this anemone; and the writer possess some such power; and this was amused by observing how varisuggestion gains a more ready cre- ously they were affected, some being dence from the tendency in most only slightly tingled, while others minds to welcome every unexplained started back as if stung by a nettle.” phenomenon as indicating an occult I think, in the face of testimony so cause. This witch-like power of fas- precise as this, we may waive all cination, — this power of paralys- negative evidence, and accept the ing with a touch, appeals to our fact of stinging as proven. But now imagination, and gains easy access to comes the question : Is this stingbelief. But the spirit of scientific ing produced by poison vesicles and scepticism forces me to declare that, spicula, as the great majority of as far as my observations and ex- writers maintain; or is it no more periments extend, there is nothing poisonous than the pricking of a like evidence in favour of this power, thorn ? Those who maintain the much evidence against it. Some ane- former opinion, explain by it the mones certainly appear to sting—as alleged cases of paralysis exhibited some jelly-fish sting--although the by the animals which have escaped majority have no such effect upon our in the struggle ; and the incident hands, which every one knows who just related of the beetle killed, but has handled them. I never perceived not swallowed (he was too large for this stinging sensation myself; and that), seems entirely to favour such Dr Landsborough says: “From my a conclusion. Nevertheless, from own experience I can say nothing as subsequent investigations I am led to this stinging power ; for though I to oppose the opinion in toto. Sir have handled not only the commoner John Dalyell—one of the best auActinize, but also the larger and less thorities--thinks that the anemone common Anthea, I never felt any conquers its prey by mere strength,
* Popular History of British Zoophytes, p. 239.