Eccentricities of the Animal Creation.
Part 20
It was long thought that the Chameleon, like most of the lizard tribe, was produced from an egg. The little animal is, however, most clearly viviparous, and not oviparous, although the tales told of the lizard tribe in the story books are most perplexing. To name a few of them:--1. The crocodile, which is the largest of the lizard tribe, and has even attained the size of 18-1/2 ft. in length, is confidently stated as laying eggs, which she covers with sand and leaves, to be hatched by the sun; and these have been met with in the rivers Nile, Niger, and Ganges. 2. _Lacerta Gangetica_, unknown to Linnæus, but brought to this country from Bengal in 1747 by the late Dr. Mead, is said to be furnished with a false belly, like the opossum, where the young can be received for protection in time of danger. In this case the egg must have been hatched in the belly of the animal, like the viper. 3. The alligator, or American crocodile, lays a vast quantity of eggs in the sand, near the banks of lakes and rivers, and leaves them to be hatched by the sun; and the young are seldom seen. 4. The cayman, or Antilles crocodile, has furnished its eggs to many collections. 5. A salamander was opened by M. Maupertuis, and its belly was found full of eggs; but in "Les Mémoires de l'Académie Royale des Sciences" it is stated that, after a similar operation of the kind, "fifty young ones, resembling the parent animal, were found in its womb all alive, and actively running about the room."
The tongue is the chief organ for taking the insects on which the Chameleon lives. By a curious mechanism, of which the tongue-bone is a principal agent, the Chameleon can protrude this cylindrical tongue, which has its tip covered with a glutinous secretion from the sheath at the lower part of the mouth, to the length of six inches. When the Chameleon is about to seize an insect, it rolls round its extraordinary eyeballs so as to bring them to bear on the doomed object; as soon as it arrives within the range of the tongue, that organ is projected with unerring precision, and returns into the mouth with the prey adhering to the viscous tip. The wonderful activity with which this feat is performed, forms a strong contrast to the almost ridiculously slow motions of the animal. Their operation of taking meal-worms, of which they are fond, though comparatively rapid, is not remarkable for its quickness, but done with an act of deliberation, and so that the projection and retraction of the tongue can be very distinctly followed with the eye.
The eyes of the Chameleon are remarkable objects; large, projecting, and almost entirely covered with the shagreen-like skin, with the exception of a small aperture opposite the pupil; their motions are completely independent of each other. It adds to the strange and grotesque appearance of this creature to see it roll one of its eye-globes backwards, while the other is directed forwards, as if making two distinct surveys at one time. Its sight must be acute, from the unerring certainty with which it marks and strikes its prey.
The Chameleons spend their lives in trees, for clinging to the branches of which their organization is admirably adapted. There they lie in wait for the insects which may come within their reach; and it has been thought that, in such situations, their faculty of changing colour becomes highly important in aiding them to conceal themselves. The powers of abstinence possessed by this singular race are very great; and hence, most probably, arose the old fable of their _living on air_, which was for a long time considered to be "the Chameleon's dish." One has been known to fast upwards of six weeks without taking any sustenance, though meat-food and insects were procured for it. Notwithstanding this fast, it did not appear to fall away much. It would fix itself by the feet and tail to the bars of the fender, and there remain motionless, enjoying the warmth of the fire for hours together. Hasselquist describes one, that he kept for nearly a month, as climbing up and down the bars of its cage in a very lively manner.
The power of the Chameleon's changing colour long exercised the ingenuity of the old naturalists. Hasselquist thought that the changes of colour depended on a kind of disease, more especially a sort of jaundice, to which the animal was subject, particularly when it was put in a rage. M. D'Obsonville thought that he had discovered the secret in the blood, and that the change of colour depended upon a mixture of blue and yellow, whence the different shades of green were derived; and these colours he obtains from the blood and the blood-vessels. Thus he says that the blood is of a violet hue, and will retain its colour on linen or paper for some minutes if previously steeped in a solution of alum, and that the coats of the vessels are yellow; consequently, he argues, that the mixture of the two will produce green. He further traces the change of colour to the passions of the animal. Thus, when a healthy Chameleon is provoked, the circulation is accelerated, the vessels that are spread over the skin are distended, and a superficial blue-green colour is produced. When, on the contrary, the animal is imprisoned, impoverished, and deprived of free air, the circulation becomes languid, the vessels are not filled, the colour of their coats prevails, and the Chameleon changes to a yellow-green, which lasts during its confinement.
Barrow, in his "Travels in Africa," declares that previously to the Chameleon's assuming a change of colour, it makes a long inspiration, the body swelling out to twice its usual size; and as the inflation subsides, the change of colour gradually takes place, the only permanent marks being two small dark lines passing along the sides. Mr. Wood conceives from this account that the animal is principally indebted for these varied tints to the influence of oxygen. Mr. Spittal also regards these changes as connected with the state of the lungs; and Mr. Houston considers this phenomenon as dependent on the turgescency of the skin. Dr. Weissenborn thinks it not unlikely that the nervous currents may directly co-operate in effecting the changes of colour in the Chameleon.
Mr. H. N. Turner, writing from personal observation of the phenomenon in a live Chameleon in his possession, says:--"It has been generally imagined that the purpose of the singular faculty accorded to the Chameleon is to enable it to accommodate its appearance to that of surrounding objects." Mr. Turner's observations do not, however, favour the idea, but seem rather to negative it. The box in which Mr. Turner's Chameleon was kept was of deal, with glass at the top, and a piece of flannel laid at the bottom, a small branching stick being placed there by way of a perch. He introduced, at various times, pieces of coloured paper, covering the bottom of the box, of blue, yellow, and scarlet, but without the slightest effect upon the appearance of the animal. Considering that these primary colours were not such as it would be likely to be placed in contact with in a state of nature, he next tried a piece of green calico, but equally without result. The animal went through all its usual changes without their being in any way modified by the colour placed underneath it. The general tint approximated, as may be readily observed, to those of the branches of trees, just as those of most animals do to the places in which they dwell; but Mr. Turner did not observe the faculty of changing called into play with any apparent object. It is only when the light is removed that the animal assumes a colour which absorbs but little of it.
Not to go further into the numerous treatises which have been published on this intricate subject without arriving at a just conclusion, we refer to the able and interesting paper of Mr. Milne Edwards, for whose acuteness the solution of this puzzling phenomenon was reserved. The steps by which he first overthrew the received theories on the subject, and then arrived at the cause of the change of colour, is shown in the following results, derived from observing two Chameleons living, and researches after the animals had died, on the structure of their skin, and the parts immediately beneath it.
1. That the change in the colour of the Chameleon does not depend essentially either on the more or less considerable swelling of their bodies, or the changes which might hence result to the condition of their blood or circulation; nor does it depend on the greater or less distance which may exist between the several cutaneous tubercles; although it is not to be denied that these circumstances probably exercise some influence upon the phenomenon.
2. That there exist in the skin of these animals two layers of membranous pigment, placed the one above the other, but disposed in such a way as to appear simultaneously under the cuticle, and sometimes in such a manner that the one may hide the other.
3. That everything remarkable in the changes of colour in the Chameleon may be explained by the appearance of the pigment of the deeper layer to an extent more or less considerable, in the midst of the pigment of the superficial layer, or from its disappearance beneath this layer.
4. That these displacements of the deeper pigment do in reality occur; and it is a probable consequence that the Chameleon's colour changes during life, and may continue to change even after death.
5. That there exists a close analogy between the mechanism by the help of which the change of colour appears to take place in these reptiles, and that which determines the successive appearance and disappearance of coloured spots in the mantles of several of the cephalopods.
Chameleons are found in warm climates of the old world, South of Spain, Africa, East Indies. Isles of Sechelles, Bourbon, France, Moluccas. Madagascar (where it is said there are seven of the species which belong to Africa), Fernando Po, and New South Wales. In the year 1860, a new and curiously formed species of Chameleon was brought from the interior of the Old Calabar district of West Africa, by one of the natives. It is characterised by three horny processes on the head. Many Lizards have singular spiny projections on all parts of the body; but this very well marked species had not been hitherto recorded.
Mrs. Belzoni, the wife of the celebrated traveller in the East, made some careful observations upon the habits of Chameleons, which are worth quoting. The Arabs in Lower Egypt catch Chameleons by jumping upon them, flinging stones at them, or striking them with sticks, which hurts them very much. The Nubians lay them down gently on the ground, and when they come down from the date-trees, they catch hold of the tail of the animal, and fix a string to it; therefore the body does not get injured. Mrs. Belzoni had some Chameleons for several months in her house, and her observations are as follows:--
"In the first place they are very inveterate towards each other, and must not be shut up together, else they will bite each other's tails and legs off.
"There are three species of Chameleons, whose colours are peculiar to themselves: for instance, the commonest sort are those which are generally green, that is to say, the body all green, and, when content, beautifully marked on each side regularly on the green with black and yellow, not in a confused manner, but as if drawn. This kind is in great plenty; they never have any other colour except a light green when they sleep, and when ill, a very pale yellow. Out of near forty I had the first year when in Nubia, I had but one, and that a very small one of the second sort, which had red marks. One Chameleon lived with me eight months, and most of that time I had it fixed to the button of my coat: it used to rest on my shoulder or on my head. I have observed, when I have kept it shut up in a room for some time, that on bringing it out in the air it would begin drawing the air in, and on putting it on some marjorum it has had a wonderful effect on it immediately: its colour became most brilliant. I believe it will puzzle a good many to say what cause it proceeds from. If they did not change when shut up in a house, but only on taking them in a garden, it might be supposed the change of the colours was in consequence of the smell of the plants; but when in a house, if it is watched, it will change every ten minutes: some moments a plain green, at others all its beautiful colours will come out, and when in a passion it becomes of a deep black, and will swell itself up like a balloon, and, from being one of the most beautiful animals, it becomes one of the most ugly. It is true that Chameleons are extremely fond of the fresh air, and on taking them to a window when there is nothing to be seen, it is easy to observe the pleasure they certainly take in it: they begin to gulp down the air, and their colour becomes brighter. I think it proceeds, in a great degree, from the temper they are in: a little thing will put them in a bad humour: if in crossing a table, for instance, you stop them, and attempt to turn them another road, they will not stir, and are extremely obstinate: on opening the mouth at them, it will set them in a passion: they begin to arm themselves by swelling and turning black, and will sometimes hiss a little, but not much.
"The third I brought from Jerusalem was the most singular of all the Chameleons I ever had: its temper, if it can be so called, was extremely sagacious and cunning. This one was not of the order of the green kind, but a disagreeable drab, and it never once varied in its colour in two months. On my arrival in Cairo. I used to let it crawl about the room on the furniture. Sometimes it would get down, if it could, and hide itself away from me, but in a place where it could see me; and sometimes, on my leaving the room and on entering it, would draw itself so thin as to make itself nearly on a level with whatever it might be on, so that I might not see it. It had often deceived me so. One day having missed it for some time, I concluded it was hid about the room; after looking for it in vain, I thought it had got out of the room and made its escape: in the course of the evening, after the candle was lighted, I went to a basket that had got a handle across it: I saw my Chameleon, but its colour entirely changed, and different to any I ever had seen before: the whole body, head and tail, a brown with black spots, and beautiful deep orange-coloured spots round the black. I certainly was much gratified. On being disturbed, its colours vanished, unlike the others; but after this I used to observe it the first thing in the morning, when it would have the same colours. Some time after, it made its escape out of my room, and I suppose got into the garden close by. I was much vexed, and would have given twenty dollars to have recovered it again, though it only cost me threepence, knowing I could not get another like it; for, afterwards being in Rosetta, I had between fifty and sixty; but all those were green, yellow, and black; and the Arabs, in catching them, had bruised them so much, that after a month or six weeks they died. It is an animal extremely hard to die. I had prepared two cages with separate divisions, with the intention of bringing them to England; but though I desired the Arabs that used to get them for me to catch them by the tail, they used to hurt them much with their hands; and if once the body is squeezed, it will never live longer than two months. When they used to sleep at night, it was easy to see where they had been bruised; for being of a very light colour when sleeping, the part that had been bruised, either on the body or the head, which was bone, was extremely black, though when green it would not show itself so clear. Their chief food was flies: the fly does not die immediately on being swallowed, for upon taking the Chameleon up in my hands, it was easy to feel the fly buzzing, chiefly on account of the air they draw in their inside: they swell much, and particularly when they want to fling themselves off a great height, by filling themselves up like a balloon: on falling, they get no hurt, except on the mouth, which they bruise a little, as that comes first to the ground. Sometimes they will not drink for three or four days, and when they begin they are about half an hour drinking. I have held a glass in one hand while the Chameleon rested its two fore-paws on the edge of it, the two hind ones resting on my other hand. It stood upright while drinking, holding its head up like a fowl. By flinging its tongue out of its mouth the length of its body, and instantaneously catching the fly, it would go back like a spring. They will drink mutton broth: how I came to know this was, one day having a plate of broth and rice on the table where it was: it went to the plate and got half into it, and began drinking, and trying to take up some of the rice, by pushing it with its mouth towards the side of the plate, which kept it from moving, and in a very awkward way taking it into its mouth."
In the autumn of 1868, a pair of Chameleons, in the possession of the Hon. Lady Cust, of Leasowe Castle, Cheshire, produced nine active young ones, like little alligators, less than an inch long. Such a birth has been, it is believed, very rare in this country. It was remarked, in the above case, that the male and female appeared altogether indifferent about their progeny.
Whatever may be the cause, the fact seems to be certain, that the Chameleon has an antipathy to objects of a black colour. One, which Forbes kept, uniformly avoided a black board which was hung up in the chamber; and, what is most remarkable, when the Chameleon was held forcibly before the black board, it trembled violently and assumed a _black colour_.[25]
It may be something of the same kind which makes Bulls and Turkey-cocks dislike the colour of scarlet, a fact of which there can be no doubt.
FOOTNOTES:
[24] The Fables of John Gay. Illustrated. With Original Memoir, Introduction, and Annotations. By Octavius Freire Owen, M.A., F.S.A. 1854.
[25] This, it will be seen by referring to page 307, does not correspond with Calmet's statement.
RUNNING TOADS.
That the Toad, by common repute "ugly and venomous," should be made a parlour pet, is passing strange; yet such is the case, and we find in a letter from Dr. Husenbeth, of Cossey, the following curious instances. Thus he describes a species, there often met with, the eyes of which have the pupil surrounded with bright golden-yellow, whereas in the common toad the circle is red or orange. This remarkable peculiarity Dr. H. has not seen anywhere noticed. The head is like that of the common sort, but much more blunt, and rounded off at the nose and mouth, and the arches over the eyes are more prominent. The most remarkable difference is a line of yellow running all down the back. Also down each side this Toad has a row of red pimples, like small beads, which are tolerably regular, but appear more in some specimens than in others. The general colour is a yellowish-olive, but the animal is beautifully marked with black spots, very regularly disposed, and exactly corresponding on each side of the yellow line down the back. Like all other Toads, this one occasionally changes its colour, becoming more brown, or ash-colour, or reddish at times, probably in certain states of the weather. This species is much more active than the common Toad. It never leaps, and very seldom crawls, but makes a short run, stops a little, and then runs on again. If frightened or pursued, it will run along much quicker than one would suppose.
During the previous summer Dr. H. kept three Toads of this kind in succession. "The first (says Dr. H.) I procured in July; but after a few days, when I let him have a run on the carpet of my parlour, he got into a hole in a corner of the floor, of which I was not aware, and fell, as I suppose, underneath the floor, into the hollow space below. I concluded that he could never get up again, and gave him up to his fate. I then began to keep another Running Toad, which fed well at first, but after three weeks refused food, and evidently wasted; so I turned him out into the garden, and have not met with him since. After more than three weeks, the former Toad reappeared, but how he came up from beneath the floor I never could conceive, or how he had picked up a living in the meantime. He was, however, in good condition, and seemed to have lived well, probably on spiders and woodlice. He had been seen by a servant running about the carpet, but I knew nothing of his having come forth again, till in the evening, when he had got near the door, and it was suddenly opened so as to pass over the poor creature, and crush it terribly. I took it up apparently dead. It showed no sign of life; the eyes were closed, it did not breathe, and the backbone seemed quite broken, and the animal was crushed almost flat. I found a very curious milky secretion exuding from it, where it had been most injured and the skin was most broken. This was perfectly white, and had exactly the appearance of milk thrown over the toad. It did not bleed, though much lacerated; but instead of blood appeared this milky fluid, which had an odour of a most singular kind, different from anything I ever smelt. It is impossible to describe it. It was not fetid, but of a sickly, disgusting, and overpowering character, so that I could not endure to inhale it for a moment. I had read and seen a good deal of the extraordinary powers of revivification in toads, but was not prepared for what I witnessed on this occasion. I laid this poor animal, crushed, flattened, motionless, and to all appearance dead, upon a cold iron plate of the fireplace. He fell over on one side, and showed no sign of life for a full hour. After that he had slightly moved one leg, and so remained for about another half-hour. Then he began to breathe feebly, and gathered up his legs, and his back began to rise up into its usual form. In about two hours from the time of the accident, he had so far recovered as to crawl about, though with difficulty. The milky liquor was reabsorbed, and gradually disappeared as the toad recovered. The next morning it was all gone, and no mark of injury could be seen, except a small hole in his back, which soon closed. He recovered so far as to move about pretty well, but his back appeared to have been broken, and one fore-leg crippled. I therefore thought it best to give him his liberty in the garden. But so wonderful and speedy a recovery I could never have believed without ocular testimony.