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Aristotle (book viii. c. 28) writes of Libyan serpents of always victorious. A negro herdsman belonging to Mr. enormous size, and relates, that certain voyagers to that Abson (who afterwards limped for many years about the coast were pursued by some of them so large that they fort) had been seized by one of these monsters by the thigh; bverset one of the triremes. The two monstrous snakes but from his situation in a wood, the serpent, in attempting (aivd mrówpa) sent by Juno to strangle the infant Her- to throw himself around him, got entangled with a tree; cules in his cradle, described by Theocritus in his 24th and the man, being thus preserved from a state of compresIdyll, exhibit some of the peculiarities of these reptiles. sion, which would instantly have rendered him quite power
The way in which Theocritus represents them to have less, had presence of mind enough to cut with a large knife,
'It may here be mentioned, that during a captivity of consists of two bones easily separable at the symphysis, or some months at Whidah, in the kingdom of Dahomey, on point of junction, while the bone similar to the os quadratum the coast of Africa, the author of this narrative had oppor- in birds, by the intervention of which it is fitted to the tunities of observing snakes more than double the size of cranium, further facilitates the act. The upper jaw morethis one just described ; but he cannot venture to say over is so constructed as to admit of considerable motion. whether or not they were of the same species, though he We next observe the spine, formed for the most extensive has no doubt of their being of the genus Boa. They killed mobility, and the multitude of ribs constructed as organs their prey, however, precisely in a similar manner; and, of rapid progression, when joined to the belly scales, or from their superior bulk, were capable of swallowing ani- scuta, with which the whole inferior surface of the body mals much larger than goats or sheep. Governor Abson, may be said to be shod. •When the snake, writes Sir who had for thirty-seven years resided at Fort William (one Everard Home, · begins to put itself in motion, the ribs of of the African Company's settlements there), described the opposite sides are drawn apart from each other, and the some desperate struggles which he had either seen, or had small cartilages at the end of them are bent upon the upper come to his knowledge, between the snakes and wild beasts, surfaces of the abdominal scuta, on which the ends of the as well as the smaller cattle, in which the former were ribs rest; and, as the ribs move in pairs, the scutum under
The exquisite beauty of the Idyll can only be equalled by the grandeur each pair is carried along with it. This scutum by its of design and execution displayed by Reynolds in his picture, + The passage cited by Valerius from Livy must have been in the lost de point from whence to set out anew.
posterior edge lays hold of the ground,
and becomes a fixed cade (the 2nd). The reader will find however the story recorded in the
This motion is beausupplement to Livy (xviii, 15).
tifully seen when a snake is climbing over an angle to get i Jonston, after quoting this passage, adds, that it is probable that the Boa grows to this size in Calabria, for that Cucciaus bishop of St. Angelo, writers its shape from a circular or oval form to something ap;
upon a flat surface. When the animal is moving, it alters in a field near the town and within his diocese, by a shepherd, and that the proaching to a triangle, of which the surface on the ground mandibles, two palms in length, were to be seen in the church of the Virgin. forms the base. The coluber and boa having large abdo (Deiparæ de Urseolo.) See Post, p.23,
minal scuta, which may be considered as hoofs or shoes, arg
(Skeleton of boa constrictor.] the best fitted for this kind of progressive motion.' (Lectures to the next muscle, and is inserted into the third rib behind on Comparative Anatomy, vol. i.)
it. The fourth set passes from one rib over the next, and Sir Everard, in the same lecture, speaking of the ribs as is inserted into the second rib. The fifth set goes from rib organs of locomotion, says-An observation of Sir Joseph to rib. On the inside of the chest there is a strong set of Banks during the exhibition of a coluber of unusual size muscles attached to the anterior surface of each vertebra, first led to this discovery. While it was moving briskly and passing obliquely forwards over four ribs to be inserted along the carpet, he said he thought he saw the ribs come into the fifth, nearly at the middle part between the two forward in succession, like the feet of a caterpillar. This extremities. From this part of each rib a strong flat muscle remark led me to examine the animal's motion with more comes forward on each side before the viscera, forming the accuracy, and on putting the hand under its belly, while the abdominal muscles, and uniting in a beautiful middle snake was in the act of passing over the palm, the ends of tendon, so that the lower half of each rib, which is beyond the ribs were distinctly felt pressing upon the surface in the origin of this muscle, and which is only laterally conregular succession, so as to leave no doubt of the ribs form- nected to it by loose cellular membrane, is external to the ing so many pairs of levers, by which the animal moves belly of the animal, and is used for the purpose of progresits body from place to place.'
sive motion; while that half of each rib next the spine, as It is not intended to detract in the least from the mas far as the lungs extend, is employed in respiration. At terly descriptions given in the lecture here quoted; but the termination of each rib is a small cartilage, in shape it is due to the sharp-sighted Tyson to observe, that the corresponding to the rib, only tapering to the point. Those locomotive power of the ribs was detected and published of the opposite ribs have no connexion, and when the ribs by him in his excellent observations on the anatomy of the are drawn outwards by the muscles, they are separated to rattle-snake. (See Phil. Trans.)
some distance, and rest through their whole length on the Sir Everard Home informs us by what additional mecha- inner surface of the abdominal scuta, to which they are connism this faculty is effected. The ribs, he observes, are not nected by a set of short muscles; they have also a conarticulated in snakes between the vertebræ, but each vertebra nexion with the cartilages of the neighbouring ribs by a set of has a rib attached to it by two slightly concave surfaces, short straight muscles. These observations apply to snakes that move upon a convex protuberance on the side of the in general; but the muscles have been examined in a boa vertebra, by which means the extent of motion is unusually constrictor, three feet nine inches long, preserved in the great, and the lower end of each vertebra having a globular Hunterian Museum. In all snakes, adds the author, the form fitted to a concavity in the upper end of the vertebra ribs are continued to the anus, but the lungs seldom occupy below it, they move readily on one another in all directions. more than one half of the extent of the cavity covered by The muscles which bring the ribs forward, according to Sir the ribs. Consequently these lower ribs can only be emEverard, consist of five sets, one from the transverse pro- ployed for the purpose of progressive motion, and therefore cess of each vertebra to the rib immediately behind it, correspond in that respect with the ribs in the Draco volans which rib is attached to the next vertebra. The next set superadded to form the wings. (See Dragon.] goes from the rib a little way from the spine, just beyond The subjoined cut, copied from that given as an illustrawhere the former terminates, it passes over two ribs, send- tion by Sir Everard Home, will explain the articulating ing a slip to each, and is inserted into the third ; there is surfaces of the vertebræ and ribs; and on the under surface a slip also connecting it with the next muscle in succession of the former will be seen the protuberance for the attachUnder this is the third set, which arises from the posterior ment of the muscles which are employed in crushing the side of each rib, passes over two ribs, sending a lateral slip | animals round which the snake entwines itself,
or spurs, he proceeds to his own observations made on Boxe
The figure above given represents the tail of a boa con
strictor : a, the vent; 6, the hook or spur of the left side ; The cut exhibits two vertebræ, and portions of two ribs of C, the subcutaneous muscle ; d, ribs and intercostal muscles; a so-called boa constrictor, drawn with his usual accurate e, transverse muscle of the abdomen; f, bone of the leg enfidelity and skill by W. Clift, Esq., from a skeleton sent veloped in its muscles; &, abductor muscle of the foot ; from the East Indies by the late Sir William Jones, and h, adductor muscle of the foot. The arrangement of the deposited in the Hunterian Museum. The letters a, a point teristic of the true boas, will be here observed. In the py
scuta, or shields, of one entire piece under the tail, characto the protuberance on the under surface for the attach; thons the shields beneath the tail are ranged in pairs. ment of the constricting muscles, according to Sir Everard Home, Though the term boa constrictor is used throughout by
2 Sir Everard Home in his lecture, there can be little doubt that the serpent sent from India by Sir William Jones was a python. The small specimen from which the description of the organs employed in progressive motion was taken may have been a boa. But whether boa or python, it would have had the books or spurs near the vent, and the bones and muscles belonging to these spurs, which are of no small consequence in the organization of a boa or a python, rudiments of limbs though they be; these appear to have escaped Sir Everard Home's observation, occupied as he
b.... was in following out the mechanism of progressive motion.
d No one can read of the habits of these reptiles in a state of nature without perceiving the advantage which they gain when, holding on by their tails on a tree, their heads and bodies in ambush, and half floating on some sedgy river, dimentary limb, taken from the same author. Figure 2.
We here have a representation of the osteology of this ruthey surprise the thirsty animal that seeks the stream. represents the left posterior limb of the Boa Scytale, seen These hooks help the serpent to maintain a fixed point ; they anteriorly: a, tibia or leg-bone; b, external bone of the become a fulcrum which gives a double power to his tarsus ; c, internal bone of the tarsus; d, bone of the meta. energies. Dr. Mayer detected these rudiments of limbs, tarsus with its a pophysis; e, nail or hook. and has well explained their anatomy*. He makes boa the first genus of his family of Phænopoda (Ophidians having
Figure 3 represents the same limb, seen posteriorly. the rudiments of a foot visible externally), adding the genera Transactions of the American Philosophical Society, held
Doctors Hopkinson and Pancoast have given in the Python, Eryx, Tortrix. After adverting to what Merrem, at Philadelphia, for promoting useful knowledge (vol. v; Schneider, Russel, Lacépède. Daudin, Oppel
, Cuvier, Oken, new series, part i.), an interesting account of the visceral and Blainville have said or figured relative to these hooks anatomy of the Python (Cuvier), described by Daudin as
the Boa reticulata. And here it may be as well to remark
• The larynx consists of a single cartilage, having a nar-
than those of snakes in general. The right lung is two • Dr. Mayer's paper appeared in the Trans. Soc. Nat. Cerios.; and was feet ten inches long, and
about four inches broad, and exafterwards translated in the Annales des Sciences for 1826. But Cuvier, whose second edition of the Règne Animal was published in 1829, does not notice it.
tends down as far as the gall-bladder; opposite the spleens,
which are on its left, it has a considerable contraction of its its unavailing show of attack, by butting at the serpent, diameter. The smaller vesicle lies on the left side, and is which now became sufficiently animated to prepare for the loose at its lower end; it is only one foot nine inches long, banquet. The first operation was that of darting out his and three inches broad; it terminates near the lower ex- forked tongue, and at the same time rearing a little his tremity of the liver. The lower four-fifths of each lung are head; then suddenly seizing the goat by the fore-leg with thin, semi-transparent, and supplied with fewer blood vessels his fangs, and throwing it down, it was encircled in an inthan the upper portion. The parietes are marked by circular stant in his horrid folds. So quick indeed and so instantalines or striæ, along which are strung small white bodies, neous was the act, that it was impossible for the eye to folapparently vesicular, from half a line to two lines distant low the rapid convolution of his elongated body. It was not from each other; they are much more numerous above, and a regular screw-like turn that was formed, but resembling appear to be merely attached to the inner surface. The rather a knot, one part of the body overlaying the other, as upper portion of each lung is composed of a more spongy if to add weight to the muscular pressure, the more effecstructure; the parietes are much thicker, and present on tually to crush the object. During this time he continued their inner surface a loose reticulated texture, somewhat to grasp with his fangs, though it appeared an unnecessary resembling a section of the corpus cavernosum penis, the precaution, that part of the animal which he had first seized. cells however being much larger. A free passage is left He then slowly and cautiously unfolded himself, till the through the centre, so that the air, in inspiration, is not goat fell dead from his monstrous embrace, when he began obliged necessarily to pass through the cells, which seem to to prepare himself for swallowing it. Placing his mouth in present merely a more extensive surface for the purposes of front of the dead animal, he commenced by lubricating with respiration. Both lungs contained many worms, found his saliva that part of the goat, and then taking its muzzle most abundant above among the cells, and even in the into his mouth, which had, and indeed always has, the aptrachea ; they were of various dimensions, being from one pearance of a raw lacerated wound, he sucked it in, as far as to three inches in length, whitish, cylindrical, tapering, and the horns would allow. These protuberances opposed some surrounded in their whole length by elevated rings or cords. little difficulty, not so much from their extent as from their
The authors of the foregoing description do not seem to points ; however, they also in a very short time disappeared, have observed a part of the mechanism of the organs of that is to say, externally; but their progress was still to be respiration detected by Joseph Henry Green, Esq., F.R.S., traced very distinctly on the outside, threatening every mo&c. That gentleman, in his lectures at the Royal College ment to protrude through the skin. The victim had now of Surgeons, after alluding to Mr. Broderip's paper on the descended as far as the shoulders; and it was an astonishing · mode in which the boa constrictor takes its prey, and of the sight to observe the extraordinary action of the snake's
adaptation of its organization to its habits, hereinafter given, muscles when stretched to such an unnatural extent- an and especially that part where the author states that the extent which must have utterly destroyed all muscular larynx is, during the operation of swallowing, protruded power in any animal that was not, like himself
, endowed beyond the edge of the dilated lower jaw, exhibited a drawing with very peculiar faculties of expansion and action at the of Two muscles which he had detected in the lower jaw for same time. When his head and neck had no other appearthe purpose of bringing the larynx forward, in consequence ance than that of a serpent's skin stuffed almost to bursting, of his attention having been drawn to the point by the still the workings of the muscles were evident; and his statement made in the paper.
power of suction, as it is erroneously called, unabated; it Without going into a detail of the anatomy of the other was, in fact, the effect of a contractile muscular power, organs given by Drs. Hopkinson and Pancoast, it will assisted by two rows of strong hooked teeth. With all this be sufficient to remark that they detected a peculiarity of he must be so formed as to be able to suspend for a time structure which suggests the idea that it is intended to ob. his respiration ; for it is impossible to conceive that the proviate the injurious effects of an impeded circulation when cess of breathing could be carried on while the mouth and the stomach is distended with food; a disteniton, from the throat were so completely stuffed and expanded by the body habits of the animal, likely to be great and of long duration of the goat, and the lungs themselves (admitting the trachea Under such circumstances they remark that the peculiarly to be ever so hard) compressed, as they must have been, by constructed vessels may, by a circuitous route, carry a large its passage downwards. proportion of blood to the heart, which the vena cava alone • The whole operation of completely gorging the goat occuwould be unable to accomplish in a state of partial com- pied about two hours and twenty minutes, at the end of pression.
which tinie the tumefaction was confined to the middle part Having endeavoured to give the reader some insight into of the body, or stomach, the superior parts, which had been the organization of these serpents
, we now proceed to lay so much distended, having resumed their natural dimenbefore him descriptions by eye-witnesses of the manner in sions. He now coiled himself up again, and lay quietly in which that organization is brought into action for the pur- his usual torpid state for about three weeks or a month, pose of killing and swallowing their prey,
when his last meal appearing to be completely digested and Mr. M'Leod, in his · Voyage of H.M.S. Alceste,' gives dissolved, he was presented with another goat, which he the following painfully vivid account of a serpent, a native killed and devoured with equal facility. It would appear of Borneo, sixteen feet long, and of about eighteen inches that almost all he swallows is converted into nutrition, for a in circumference, which was on board. There were ori- small quantity of calcareous matter* (and that perhaps not ginally two; but one, to use Mr. M'Leod's expression, a tenth part of the bones of the animal), with occasionally sprawled overboard and was drowned.'
some of the hairs, seemed to compose his general fæces.... During his stay at Ryswick,' says Mr. M'Leod, speaking • It was remarked, especially by the officers of the watch, of the survivor, “he is said to have been usually entertained who had better opportunities of noticing this circumstance, with a goat for dinner, once in every three or four weeks, that the goats had always a great horror of the serpent, and with occasionally a duck or a fowl by way of a dessert. The evidently avoided that side of the deck on which his cage live-stock for his use during the passage, consisting of six stood. P. 305. gcats of the ordinary size, were sent with him on board, Mr. Broderip, in the second volume of the Zoological five being considered as a fair allowance for as many months. Journal,' after referring to Mr. MʻLeod's interesting narra
At an early period of the voyage we had an exhibition tive, of the correctness of which, as far as it goes, he says he of his talent in the way of eating, which was publicly per- has not a single doubt, and observing that two points in formed on the quarter-deck, upon which his crib stood. The that description struck him forcibly, the one as being consliding part being opened, one of the goats was thrust in, trary to the probable structure of the animal, and the other and the door of the cage was shut. The poor goat, as if as being contrary to Mr. Broderip's observations, proceeds instantly aware of all the horrors of its perilous situation, to give the following account of the manner in which the immediately began to utter the most piercing and distressing serpent 1 takes its prey in this country. cries, butting instinctively, at the same time, with its head towards the serpent, in self-defence.
• This was most probably the urine of the animal, which is often voided in
inspissated lumps, like moist plaster-of-Paris in appearance, and has been fre* The snake, which at first appeared scarcely to notice the quently taken for fæces. Dr. John Davy describes it in the Philosophical poor animal, soon began to stir a little, and, turning his Trausactious as of a butyraceous consistence, becoming hard like chalk by
exposure to air, and as being a form of pure uric acid. bead in the direction of the goat, he at length fixed a deadly
† The serpent whose actions are described by Mr. Broderip, and that which and malignant eye on the trembling victim, whose agony furnished Me. M·Lrod's narrative, were Indian boas or pythons. These lava and terror seemed to increase ; for, previous to the snake thongh, as we Wave already stated, there nre points of difference in the website seizing his prey, it shook in every limb, but still continuing meut of the scuta below the vent, &c., the general structure of the true South
Mr. Cops of the Lion Office in the Tower,' writes the pulmonary system of a boa*, or of satisfying myself as Broderip, sent to inform me that one of these reptiles had to the structure of the extremely long trachea, which must just cast his skin, at which period they, in common with be very firm to resist such an immense pressure, but I other serpents, are most active and eager for prey. Ac- believe, from a near and accurate inspection, in company cordingly I repaired with some friends to the Tower, where with others, that respiration goes on during the period of we found a spacious cage, the floor of which consisted of a the greatest dilatation. While these serpents are in the tin case covered with red baize and filled with warm water, act of constringing or of swallowing their prey, they appear so as to produce a proper temperature. There was the to be so entirely pervaded by the õpetist which then governs snake, “positis novus exuviis," gracefully examining the them, that I am convinced they would suffer themselves to height and extent of his prison as he raised, without any be cut in pieces before they would relinquish their victim. apparent effort, his towering head to the roof and upper I have assisted in taking them up and removing them with parts of it, full of life, and brandishing his tongue.
their prey in their coils, without their appearing to be in • A large buck rabbit was introduced into the cage. The the least disturbed by the motion, excepting that, if after snake was down and motionless in a moment. There he the victim is no more and the constriction is somewhat reJay like a log without one symptom of life, save that which laxed, an artificial motion be given to the dead body, they glared in the small bright eye twinkling in his depressed instantly renew the constriction. When thus employed head. The rabbit appeared to take no notice of him, but they may be approached closely and with perfect security presently began to walk about the cage. The snake sud- for the reason above stated, and I have uniformly found denly, but almost imperceptibly, turned his head according that the larynx is, during the operation of swallowing, proto the rabbit's movements, as if to keep the object within truded sometimes as much as a quarter of an inch beyond the range of his eye. At length the rabbit, totally un- the edge of the dilated lower jawi. I have seen, in company conscious of his situation, approached the ambushed head. with others, the valves of the glottis open and shut, and The snake dashed at him like lightning. There was a the dead rabbit's fur immediately before the aperture stirred, blow-a scream-and instantly the victim was locked in apparently by the serpent's breath, when his jaws and the coils of the serpent. This was done almost too rapidly throat were stuffed and stretched to excess. In the case for the eye to follow: at one instant the snake was motion above mentioned, where the prey was taken very awkwardly, Jess ; in the next he was one congeries of coils round his and the dilatation was consequently much greater than prey. He had seized the rabbit by the neck just under usual, I saw this wonderful adaptation of means to the the ear, and was evidently exerting the strongest pressure exigencies of the animal much more clearly than I had round the thorax of the quadruped; thereby preventing the ever seen it before. expansion of the chest, and at the same time depriving the With regard to the next point, it is more difficult to acanterior extremities of motion. The rabbit never cried count for the variance between the agony of antipathy after the first seizure:-he lay with his hind legs stretched shown by the goat as described by Mr. M.Leod, and the out, still breathing with difficulty, as could be seen by the indifference which I have uniformly observed in the full motion of his Hanks. Presently he made one desperate grown fowls and rabbits presented to these serpents for struggle with his hind legs; but the snake cautiously prey. Immediately after our boa had swallowed his first applied another coil with such dexterity as completely to rabbit, a second was introduced ; but the serpent now exhimanacle the lower extremities, and, in about eight minutes, bited a very different appearance. The left side of his the rabbit was quite dead. The snake then gradually and lower jaw was hardly in its place, and he moved about the carefully uncoiled himself, and, finding that his victim cage instead of lying in wait as on the former occasion. As moved not, opened his mouth, let go his hold, and placed for the rabbit, after he had been incarcerated a little while, his head opposite to the fore part of the rabbit. The boa he treated the snake with the utmost contempt, biting it generally, I have observed, begins with the head; but in when in his way, and moving it aside with his head. The this instance the serpent, having begun with the fore-legs, snake, not having his tackle in order, for his jaw was not was longer in gorging his prey than usual, and in conse- yet quite right, appeared anxious to avoid the rabbit, which quence of the difficulty presented by the awkward position at last stumbled upon the snake's head in his walks, and of the rabbit, the dilatation and secretion of lubricating began to treat it so roughly, that the rabbit was withdrawn mucus were excessive. The serpent first got the fore-legs for fear of his injuring the snake. This treatment of the into his mouth; he then coiled himself round the rabbit
, snake by the rabbit did not appear to be the effect of anger and appeared to draw out the dead body through his folds ; or hatred, but to be adopted merely as a mode of removing he then began to dilate his jaws, and holding the rabbit something, which he did not appear to understand, out of firmly in a coil as a point of resistance, appeared to exercise his way. I have seen many rabbits and fowls presented to at intervals the whole of his anterior muscles in protruding different specimens of boa for prey, and I never saw the his stretched jaws and lubricated mouth and throat at first least symptom of uneasiness either in the birds or quaagainst, and soon after gradually upon, and over his prey. drupeds. They appear at first to take no notice of the The curious mechanism in the jaws of serpents which serpent, large as it is, and when they do discover it they do enables them to swallow bodies so disproportioned to their not start, but seem to treat it with the greatest indifference. apparent bulk is too well known to need description; but it I remember one evening going up into the room where one may be as well to state that the symphysis of the under of these snakes was kept at Exeter 'Change, and seeing the jaw was separated in this case, and in others which I have hen which was destined for the prey of the boa, very comhad an opportunity of observing. When the prey was com- fortably at roost upon the serpent. The keeper took the pletely ingulphed, the serpent lay for a few moments with hen in his hands and held it opposite to the head of the his dislocated jaws still dropping with the mucus which had snake, without succeeding in inducing him to take the bird, lubricated the parts, and at this time he looked quite suffi- which, when let out of the keeper's hands again, settled ciently disgusting. He then stretched out his neck, and herself down upon the serpent for the night. at the same moment the muscles seemed to push the prey • The only solution which I can offer of the difference befurther downwards. After a ew efforts to replace the tween Mr. M.Leod's description and my experience, is one parts, the jaws appeared much the same as they did pre- which I do not propose as absolutely satisfactory, but which vious to the monstrous repast.
may nevertheless be found to approach the truth. The 'I now proceed to the first of the two points above alluded goats put on board at Batavia for the serpent, which it apto, and have to state my opinion that the boa constrictor pears was brought from Borneo, were in all probability does respire“ when his head and neck have no other appear- natives of Java, and if so, they would, according to the ance than that of a serpent's skin stuffed almost to burst- wonderful instinct which nature has implanted in animals ing;" and I think that, upon a more close examination, the for their preservation, be likely to have a violent antipathy same phenomenon would have been observable in the ser- to large serpents, such as those which there lurk for their pent shipped at Batavia. It is to be regretted that the prey. The great Python is a native of Java, and if these dissection of that serpent appears to have been confined to goats were wild, or originally from the wild stock of the the stomach ; at least nothing is said of any other part of island, their instinctive horror at the sight of the destroyer the animal. I have never had an opportunity of dissecting may be thus accounted for. But our domestic fowls and
rabbits (the stock of the latter most probably indigenous, American boa so much resembles that of the Indian hoa, or python, and the and that of the former of such remote importation, and so habits of both, particularly in taking their prey, are so similar, that a true much changed by descent, as to be almost on the same description of the predatory habits of the python will give a satisfactory idea pf those of the boa,
See ante, p. 22. † Appetite. * See ante, p. 23.