Vipera Caudi-Sona Americana, Or the Anatomy of a Rattle-Snake, Dissected at the Repository of the Royal Society in January 1682/3 by Edw. Tyson M.D. Coll. Med. Lond. Cand. & R. S. Soc.

PHILOSOPHICAL TRANSACTIONS. February 10, 1685. The CONTENTS. VIPERA CAUDISONA Americana, Or the Anatomy of a Rattle-Snake dissected at the Repository of the Royal Society in January 1685 by Edward Tyson M.D. Coll. Med. Lond. Cand. & Reg. Societar. Soc. An Account of some Books: I. Martini Lister & S. R. Lond. DE FONTIBUS MEDICATIS ANGLIAE Exercitatio nova & prior. II. Jo. Alphonsi Borelli Neapolitani Matheos Professoris DE MOTU ANIMALIVM Opus Posthumum. VIPERA CAUDISONA Americana, Or the Anatomy of a Rattle-Snake, Dissected at the Repository of the Royal Society in January 1685 by Edw. Tyson M.D. Coll. Med. Lond. Cand. & R. S. Soc. The Observations I shall here give are such as a single Subject would afford, not what might compleat the History of so Curious an Animal. And tho it were mightily to be wisht that we had at least the most accurate account, and exactest Anatomy, of one of every distinct Species of Animals; yet this can't be expected but of those those that are most common; where frequent repeated Dissections might fully inform us of Natures admirable contrivance, and Mechanism of Animal Bodies. This which We Dissected was sent to Mr. Henry Loades, a Merchant in London, from Virginia; who was pleased not only to gratify the curiosity of the R. Society in shewing it them alive, but likewise gave it them when dead, and so afforded them an opportunity of farther satisfaction in observing the inward parts of it; which I find so conformable in almost all respects to those of a Viper, that I have taken the liberty of placing it in that Class, and (since it has not yet, that I know of, any Latine Name) of giving it that of Vipera Caudifona; for as I am inform'd by Merchants, 'tis Viviparous, and the Epithet sufficiently differences it from those that have no Rattle, although of these too there ought to be made a Subdivision. But I shall concern myself at present only with the Anatomy, which I think is yet given by None; tho to me it seems the most principal part in a Natural History of Animals; and for other Accounts I shall refer to Georg. Marcgravius, Gul. Piso, Johnston, Nierembergius, Joan. de Laet, Fran. Hernandez, and others that have wrot of it; who describe it under the Names of Boicininga, or Boipinininga, and Boiquira, which are the Brazil Names. By the Portugues's 'tis called Cascavela and Tangador; by the Dutch, Raatel-Schlang; by those of Mexico, Teutlacocauhqui, or Teuhtlacotzaubqui, (i.e.) Domina Serpentum, and from its swift motion on the Rocks like the Wind, Hooacoatl. But as to our Business, before we look within we shall take a short survey of its outward parts. This therefore that we dissected was 4 foot 5 Inches long; the girth of the Body in the largest place, which was the middle, was 6½ Inches; the girth about the Neck 3 inches; near the Rattle 2 inches; the Head flat on the top as is the Viper, and by the protuberance of the Maxilla somewhat representing the head of a bearded arrow; at the extremity of it were the Nostrills, between them and the Eyes, Tab. Figs. but somewhat lower, were two other Orifices, which I took for the Eares, but after found they only led into a bone that had a pretty large cavity, but no perforation. Vipers have not these orifices in the head; and Charas saith that they hear by the Nostrills; and that to them run not only the Olfactory, but Auditory Nerves also. The Eye was round, about $\frac{1}{4}$ of an Inch diameter; in Colour, the make of the Pupil, and other respects, like a Viper, as indeed except in the Rattle, was the whole external shape of this Animal. There was a large Scale jetting over the Eye, which seemed to serve as a Palpebra for defending it from any thing falling on it; but I could not perceive 'twas capable of closing, tho inwards it seem'd to have a membrana nititans, which removes any dust that might adhere to the Eye. The scales on the head were the smallest of any; those on the Back larger, and so proportionably greater to the biggest part of the Body; and so diminishing thence again to the setting on of the Rattle; all in figure somewhat resembling Parsnip Seeds. Their colour various; those on the Head, like the colour of the feathers on the back of a Green-finch; speckled with small black spots; whereof there were four larger and more remarkable. Those on the back were a dark Feullemorte, a black and a darkish yellow, and speckled, making a curious chequer or dappling on the back by this intermixture of colours; but as they grew nearer the Tail they became darker, and at last almost Black. The Scales on the back had an edged rising in the middle, which was still less protuberant as they grew nearer the sides, where they were flat. The Belly seemed flat, covered with long Scales of a yellowish colour, speckled black. From the Neck to the Anus we number'd 168; beyond the Anus were two half Scales; thence 19 whole scales of a black lead colour with yellowish Edges; from thence to the Rattle 6 orders or rows of smaller scales of the same colour. The scales of the Belly were joyn'd to each other by distinct muscles; the lower Tendon of each muscle being inserted into the upper edge of the following scales and the other Tendon of the same Muscle inserted about the middle of the foregoing scale. These * Muscles were more fleshy towards the middle of the scale; and then its fibres did run obliquely ascending. To each scale was appropriated a Rib, whose point did joyn with the extremity of it, which must much advantage the use Nature seems to design them for, by strengthening them to perform their reptile motions; for the scales are as so many feet, which being free, and open downwards, they thereby take hold of the ground, and so contract their body forwards, and then shoot out again, and so perform their motion. Whence tis observed by * Nicrenbergius, that on Rocks their motion is much quicker, than on the Earth, or Plains; which he needed not to make a wonder of, since here they have the firmer footing. But in soft ground, tho their belly be flat, yet they can contract it to an Ellipsis or an acute angle, that so they may take the deeper hold, as I have observed in a Viper. Since they must be always grovelling on the ground, 'tis a great provision of Nature in furnishing them with this coat of armor for their defence; which is so curiously contrived, that tho it covers the whole, yet by its frequent jointings it admits of all motions. And for this too, the vertebrae of the spine seem admirably contrived; there being a round ball in the lower part of the upper vertebra, which enters a socket of the upper part of the lower vertebra; as the round head of the Thigh bone does the acetabulum of the os Ischii, by which means it can turn itself any way. Having placed it on its back, we opened it; and observed that the Tendons of the Abdominal muscles made a linea alba in the midst of the scales of the Belly; where likewise did run a large * blood Vessel, arising from the Vena *Fig. x. rr. cava, towards the lower part of the Liver. But not to be too nice here, we proceeded to examine the Viscera, and shall here give the remarks in short, which I made of the Windpipe, Lungs, Oesophagus, Stomach, Guts, Heart, Liver, Gall-bladder, Spleen, Kidneys, Organs of generation, the Sent-bags, and then described the Head, the Venomous Teeth, the Skeleton and Rattle; and for the better Understanding the Uses of these parts, we shall often make a Comparative Survey of them with those of other Animals. The Windpipe here was differing from that of most other Animals; which usually having their cartilages annular, or at least conjoined by a membrane, do form a fissula for conveying the air into the Bronchia; which thence is transmitted into the small Bladders of the Lungs. But here, which is common with it to the Viperkind, as soon as it enters the breast, presently meeting with the Lungs, it consists only of semi-annular Cartilages; which being joined at both ends to the membrane of the Lungs inwardly is quite open, and immediately transmits the air to the Vesiculae of the Lungs as will better appear by the figure. For dividing the Windpipe we perceived it easily extended above 1½ Inch wide; whereas before it meets with the Lungs the Cartilages are annular. The Trachea or Windpipe was 20 Inches long, terminating near the Heart and beginning of the Liver, and reaching to that part of the Lungs which made the great bladder. The Cartilages of the Trachea near the beginning were ½ of an Inch, but toward the end ¼ of an Inch, and lying flatish from end to end. These Cartilages were not so distinct as in other Animals; but often running into one another. The Use of the Trachea is plain, for conveying the air into the Lungs; which how considerable an Organ they are Nature seems to shew us by the admirable contrivance, and Largeness of their Structure. They begin from the Throat, and run down 3 Foot in length. * The upper part of them that lay in the fore part of the body for the length of a foot, and did reach to the Heart, was made of small Vesiculae or Cells, like the Lungs of a Frog; but from the the frequent branchings and chequer of the blood vessels there, appeared of a florid red. This part tapers proportionably to the Body; the lowest part of it near the Heart moderately blown, was in compass 5½ Inches; a little lower, for the space of 4 Inches, the cells gradually disappeared; so that they seemed at last to form only a reticular compages of valvulae conniventes on the inside of the membrane of the Lungs; and the compass of the greatest place here was about 6½ Inches; but from thence to the end of the Lungs was only a large* Bladder * without any Cells; composed of a thin, but strong transparent membrane, the compass of which blown as the former was 8½ Inches. The Lungs of the Salamandra Aquatica, and some other Animals, are only two large bladders. In the Frog, Crocodile &c. are two large lobes, filled with membranous vesicula or Cells. Our Rattle-snake, and all that Family, tho they have but one lobe of Lungs, yet in that they comprise the 2 former Sorts; the fore part being filled with numerous Vesicula; the later an entire large bladder. In the land-Tortois there are two tubes, one on each side; but these are subdivided into several others, according to the partitions of the Ribs that are fixed to the shell; and they ly chiefly in the belly, that is, the lower part of the body. But what I would remark is, that where the Bronchie first enter these subdivisions 'tis reticulous; then they form a large cavity: so that in these Animals, where the nixus of Respiration is not so frequent, Nature provides a sufficient store-house for this (so necessary a Pabulum vitae) in these larger bladders, whence tis dispenced according to the exigency of the Oeconomia Animalis. For the Tortois, Viper, Rattle-snake, Frogs, Toads &c. which sleep a great part of the year; as before they betake themselves to this repose, they take in their store of Food; so perhaps that of air too, a more constantly requisite supply of Life. For when thus stupidly asleep, and sometimes to all appearance Dead; it may be questioned ned whether they have any motion of those parts, which is required for drawing in fresh Air in inspiration. But since their life here is so imperceptible and small; this stock may be sufficient, the decay being so little. So the Salamandra aquatica, that lives under water, for Lungs has two large Bladders, not unlikely for this Reason; that it might not be forced so often to raise itself out of the Water to breath in fresh air when the former is spent and decayed. In a Viper I lately Dissected, which remained alive some days after the Skin, and most part of the Viscera were separated, I observed the Lungs all this while not rising and falling, as in Inspiration, and Expiration, but constant, equally extended with Air; that as soon as it dyed, it expired, and they fell. But the Stomack was empty, and I doubt not was so some considerable time before; as was the Rattle-Snake's, which for 4 Months at least had eaten nothing: so that although they can live so long without Food, yet Nature is mighty provident in supplying them with Air, in bestowing on them so large Receptacles for receiving it. So the Ephemeron, the Silkworm and other Butterflies, which all their life time, when in that state, do not eat, or take in any food, yet have their Bronchie, or Lungs, remarkably large, and numerous, as if they were sufficient alone for maintaining their Life, for if they be occluded with Oyl, or otherwise, they are strait suffocated, and dye convulsed. But wee shall now take notice of those parts that are for receiving the Food; And first of the Oesophagus, or Gula, which serves for the transmitting it into the stomack; and indeed this seems the only use of this part in most other Animals; but here Nature may be thought to intend it for something more, and to make use of it upon occasion as a Stomack, or Stomacks too; for upon blowing up this part, I observed two large swellings, as represen- --- b Narrant multi, qui cum Serpentem domi alere solent atque educare, annum integrum durare absque cibo allo potuque, Nicrenberg. Hist. Nat. l. 12. cap. 1 ted in the Figure; nor was the true Stomack capable of that extension as these were. The whole length of the Oesophagus was two Foot 3½ Inches; the length of the proper Stomack 5 Inches, lying in a strait line with the Oesophagus, but thicker than it, having a remarkable coat more on the inside, easily distinguishable by its colour, substance and Plica, and jetting over the inside of the Gullet; and in all respects as in the Viper. From the Pylorus the Ductus straightened again for 1½ inch; and then formed a large Intestine, which afforded a pleasant sight, by the weaved Ruge of its inward coats; which Gut after some small windings, ended at last in the Rectum, whose capacity was much less than the former. In the Stomack and Guts I observed abundance of Lumbrici teretes which is a disease Vipers likewise are subject to. The whole length from the Throat to the Anus, is but a continued Ductus; tho oft variously distinguished, according to Natures different intention in the several species of Animals; in none is so plain and Simple, as in the Atus Marinus, where you have neither Oesophagus or Stomack, but only a strait passage, and that too without any valves, only growing a little more taper towards the Anus. In other Fish there is no Oesophagus; in some but a very short one. In other Animals tis not only long, but by its swellings in some places, has acquired different Names, as the Ivgluvies, or Crop in Birds; the Paunch or Median ronicle in Quadrupeds; and what use they do perform the same I take these swellings in the Gullet of the Rattle Snake to doe likewise; they being convenient receptacles for retaining what Food the Stomack cant yet well receive; and here it seems the more requisite, since they feed but at one time of the year. But since in that promiscuous food they take, in which they swallow always whole, there are often some parts unfit to be digested, and therefore to be returned again; the Gullet here being very long, and upon that account inconsiderious for this action, Nature has provided these swellings ings in it, where they may be respited, till recounting its force, it gives them another list, and upon a third effort at last wholly ejects them. And if what is confidently reported by many, be true, that on occasion of danger they receive their young into their mouths, these are fit places for receiving them. The food before it can prove aliment, must be comminuted, and broken into the smallest particles; which in these membranous stomachs, I can't see how it can be performed, but by corrosion. A principal menstruum in doing this, I take to be that liquor, which is discharged by the Glands that are seated in some fat the beginning of the Throat, and are called Salival, or just above the Stomack or Gizzard of Birds, and called the Echimus, or in others in the stomack itself, and called the glandulous coat; and such I take the inward coat of the stomack of our Rattle-Snake to be. When comminuted tis discharged into the Guts; which that the Chyle might not pass off, with the Faeces, are often convoluted, or winding as * here; that so by impeding a too quick descent of it this way, or by Valves, a separation may the better be made; and then the Faeces as useless, can't quicker be discharged than by the rectum; which where the Faeces are hard, is furnished with a stronger muscle the better to help its action; and such seemed the rectum here; and the Faeces harder than usual in Vipers. So that the whole Dubus Alimentalis from its uses, may ordinarily be divided into 4 parts. 1 That which conveys the Food, the Oesophagus. 2 That which digests or corrodes it, the stomack. 3 That which distributes the Chyle, the Intestines. 4 That which empties the faeces, the Rectum. But a Leech is all stomack, from one end to the other, and do's devour at a meale several times the weight of its whole body: The stomack when swell'd and strecht with blood is far bigger than the Leech it selfe; nay several times exceeds it. But I mistook the number, it was not one, but many Stomacks; for the cavity is divided by several transverse membranes, into divers distinct camera's; but these membranes in the middle have a hole that leads from one into the other: but by the pouching out of each side, each of these may be reckoned also two; in all we may number, (there being 10 or 11 of these camera's, besides those 2 long ones which at last run to the tail) at least two, if not four and twenty Stomacks, but the Rectum which lies between the forking of the 2 last long Sacculi, or Stomacks, is but small, and short in respect of the whole; but of this perhaps more in my Anatomy of this Animal. To proceed We shall next take notice of the † Heart, which was placed near the bottom of the Trachæa, on the right side of it. The length of it was 1 Inch, its figure rather flat than round; encompassed with a Pericardium, and the * Auricle larger than the heart itself. It hath but one Ventricle, the valves small, and fleshy: and the inside of the Ventricle distinguish't by 4 or 5 cross furrows. Why Charas should make the Heart of the Viper to have two Ventricles, I see no reason; I should much more easily allow a double Auricle, one at the entrance of the Vena cava of which there are two || branches descending and one ascending; the other for the Arteria Aorta, which has two ascending and one descending || branch as in the || figure. A little below the Heart lies the * Liver; which was about an Inch wide in the largest place, and seemed divided on one side by the Vena cava into two lobes of an unequal length; for that on the left side was about 10 inches, and that on the right side about a foot long; its colour a brown red, and its use no doubt for the separating the Gall that was contained in a † bladder seated at some distance below it. It was once the opinion of Sylvius, that the Gall was transmitted hence into the Liver to be mixed with the blood, and not there separated from it; but what the famous Malpighi wrote to the contrary, in a great measure brought him off it: and our Subject here, is an Ar- Argument against him, where the Gall Bladder is placed so remote from the Liver, and the Ductus for conveying it into the Intestine, is so evident, whereas that which brings it from the Liver is more obscure, and hard to be found. The Gall-bladder here was 2 Inches long, the colour of the Gall contained in a grass-green, which swearing through its coates had deeply tinged all the adjacent parts, the taste of it in a Viper which seems the same, for I did not taste it here, was first salt, then a sweet bitter. The Ductus Cysticus, by which it empties itself into the Intestine, arises from the top of the Bladder; so gently descending passes through that part which Charas takes for the Pancreas, but which the Ancients called the Spleen, and so enters the beginning of the large Intestine. Indeed in Vipers, the Colour of this part, and situation so neare the Intestine, seems an Argument for Charas his conjecture, for he modestly proposes it as such; but here in our Subject, its Colour which was deep red, and such hitherto I have observed the Pancreas to be in no Animal, as likewise its figure, not spreading but more compact, these seem to favour the Opinion of the Ancients; I shall move no controversy about this part, which has made so many with all Anatomists; having little to say of it, but that 'twas about the bigness of a large bean; that it adhered to the side of the Intestine at the begining of it; and that through the middle of it, as is already observed, the Ductus Bilarius did pass. I was taken off from a farther Scrutiny into this part by the ravishing beauty of another, I shall presently describe, the Kidneys. But I must first observe the Fat which was very plentiful and is said by Nardus Anton. Recchus to be used by the Physicians of Mexico with good success, in the Sciatica and all pains of the Limbs, and for discussing preternatural Tumors. The Membrane it adhered to, I take for the Omentum; --- c Perum Med. Nova Hispan. Hisp. lib. 9. c. 17. p. 318. which encompassed all parts contained in this lower Belly; and was joined to both sides of the Ribs, so running to the Rectum, and forming a bag that enveloped the parts here, but was free, and not conjoined towards the Belly. The lower Belly I call it to distinguish it from the rest of the Trunk, for the whole was but one continued cavity; there being no partition of it by any Diaphragm; and I have represented the parts contained here, in my second Figure, as the others are in the First; but proportionably much larger as appears by the Descriptions. For the two Kidneys, which lay to the back on each side of the Spine, but not very firmly conjoined, were about 7 Inches long; that on the right side something longer than the left; and about \(\frac{1}{2}\) Inch broad each; tho one continued body, yet plainly distinguishable into several lesser Kidneys, as I remember in one I numbered 15, but all so very curiously contrived and with so great beauty, that I want Words to express what the Pencil could not imitate, much less can be represented in a Print. I shall therefore in my Description, the better to help out and illustrate my meaning, have a constant reference to the Figures; which being covetous of making as well as might bee, spent so much time, that I had not an opportunity of satisfying my curiosity in all respects (the parts drying) as I desired; but did observe, as likewise several Others who viewed them, when first taken out of the body, that the whole seemed a delicate Compages of vessels, and the intermixture of those of the blood, with those other white ones, that are the Secretory, composed most regularly formed Bodys. In my* figures, That on the left side represents the upper superficies of the Kidney, which appears first in the Dissection; the other, the lower side which lies to the back; in both there are two large blood vessels running down each side; one marked (\(n n n\)) the other, where the vas deferens runs; but is not here represented; and from these arise several lesser branches (\(o o o\)) at set distances, which curiously spreading themselves do form... as it were ramifications of Trees. As many as there were of these emulgent vessels (for so I take them to be) so many Kidneys were in each; the Interstices (ppp) of these blood vessels were filled up with other White ones; which I doubt not are for the secretion of the urine, and on this side did appear more numerous, than on the other; but tis impossible to represent the curious interweavings of both; but here in the under side of the right Kidney in some places they appeared more distinct; for (QQ) shows the large blood vessel, whence arises the Emulgents (rrr) which spreading themselves very thick into the bodys (sss) make them appear all bloody, between which for a little space there appears a small body of the White Secretory vessels (ttt) This curious structure of the Kidneys, and peculiar order of the vessels, do further confirm me in my opinion concerning the make, and fabric of these parts; but having at large delivered my thoughts hereof, in my Adenologia or Discourse concerning the Glands of the Body which it may be I may hereafter publish; I shall not at present further insist upon it: but shall only remark, that in Birds, Fish, and Reptiles, the Kidneys are usually long; in other Animals often more compact; the several Glandulous bodys that compose them being conglomerated, and closer set together, tho in some they appear perfectly distinct: as the Bear, the Otter, the Porpoises, Ostridge &c. and as I have remarked in the Porpoises, in each of these there may be observed distinct Emulgents, ureters, Pelvis, a Cortical or Glandulous part, and the Corpus Papillare, which is made up of the Tubuli urinarii, which convey the Urine into the Pelvis. And the Kidney in a man tho it seems but a single one yet it is really made up of as many, as there are Corpora Papillaria. So here in our Subject, tho the Substance of the Kidney seems continued, yet there ought to be reckoned as many as there are distinct --- d Phocaia or the Anatomy of a Porpoise p. 24. systems and Orders of vessels; each making a peculiar gland or small Kidney; which according to the advantage of the body of this Animal, are placed here at length, not piled on one another. The use of them is for carrying off the Lixivial and superfluous Serum of the blood, which is of so great consequence, that even those Animals that drink not at all, or but very little, yet by Nature are furnished with them, as the Rattle Snake may be thought. When the separation of this humour is made in the Kidneys, 'tis conveyed thence by the ureters, into a bladder, if the too frequent exclusion of it might be inconvenient to the Animal, or if it be made in lesser quantity, into a Cloaca, just at the Anus, and so to be ejected. The Ureters in our Subject did run almost the length of the Kidneys: being a common Trunk that received the lesser Branches that went to each single Gland; it is in part represented by the * letters [v.v.] and did both terminate near each other in the Cloaca, making a rising there; for our Rattle Snake, like Birds, had a Cloaca, which in the female viper, receives the Orifices of the Ureters, and the two Uteri; and in part may be said that of the Rectum too, which yet had a convenient Valve that covered it. Near the Verge of the Cloaca, we observed two other orifices which seemed covered by the folding of the Skin, and these led into those two † Baggs which I have taken the liberty to call the Scent-baggs. Charas is much mistaken, who supposes them to be the Parastates or Conservatorys of the Seed, as likewise those he would refute that would have them to be other Testicles: and I the more wonder at this his mistake, since he could not but have observed them as I have in the female Vipers too; which sufficiently shews his error. One of them was about an Inch long, and as big as a Goose quill, but Taper towards the end, and from the colour of the Liquor it contained, appeared darkish; the other Bagg was something less, and its colour colour as in the Viper. This difference I suppose may be accidental: The Liquor included in them was something gross, and of a strong and very unpleasant Smell; such, but in a more intense degree, as the Animal did emit before dissection, which Martial likewise takes notice off, having placed it in the last but one in his Catalogue of Stinks, where he saith Quod Vulpis fuga, Vipere cubile, Malles, quam quod oles, olere Baffa. And Jo. de Laet makes mention of some Snakes in the West Indies that stink worse than any Fox or Pole-cat. I have long since taken notice how the Fators of all strong scented Animals, are collected in these Baggs, but designing there may be hereafter a farther Essay on this Subject; I shall not here inlarge upon it: Only take notice, that our common Snakes have a far greater Factor (Which lies in the same baggs) than our Adders or Vipers. And I have been told by Travellers, that some Crocodiles will leave a strong, but grateful Smell behind them: which if so I doubt not, but it may be upon the same cause. But usually tho this Liquor when new, and in great Quantity be offensive, and of an ill smell (and such is Civet likewise which is nothing else) yet when dry and in lesser Proportions it may prove more grateful. Thus the liquor in the Scent baggs of a Weasell, being dried, on a Paper and kept some time, did not seem unpleasant to me; but rather the contrary: and I see no reason why Pole-Cats may not be Civet-Cats, though they may not turn to that account. But in a Lyon I dissected, the Liquor contained in the Scent-baggs was in the opinion of all that smelt it, much like that of Oyl of Anise or Fennel seed; which almost was the only difference I could find between the Lyon and a Cat; for in a Cat this Liquor is scented. d Martial: l. 4. Epigr. 4. e Hist. India Occident. l. 15. c. 6. p. 555. f In Dr. Plot's Natural Hist. of Oxfordshire. c. 9. p. 325 But we shall now come to the organs of Generation: and I find that Charas is as unhappy in the Description of some of them, as he was in his conjecture about that part, we call the Scent-bagg. We shall begin with that, wherein the Seed is first made, the * Testes, which are very unproportionate in length; the Right being 2 1/4 inches long, the Left but 1 1/4 inch long, scarce so big in compass as a Goose-quill. The unequal length of this part Charas takes notice off in Vipers. I shall add, that the Ovarium of the Female Viper is the same; for that of one side was as big again as the other. The colour of the Testes was white, as is usual, and so was their Substance. I did take notice of the Vasa preparantia, which had nothing uncommon: But the † Deferentia were remarkable; for tho they did run in a strait line almost from the Testes to the Penis, and did form no large body, yet this Ductus was so often involved, that were it unravel'd and extended its whole length, 'twould be twice as long: which made me think, that it was only the extention of the Epidydyms, for the whole Testis is but a Cangeries of curiously convoluted Vessels which terminate in the Epidydyms, whose continuation makes the Deferens: and where its convolutions are many upon the Body of the Testis itself, there the Deferens is an even Ductus; but as in our subject it making no such body there, or but a very small one, in its passage downwards it was everywhere crimped, and about the middle of the Kidneys often convoluted, which is represented in our Figures. Where they emptied themselves I could not so well observe in the Rattle Snake; Since the parts which I had laid out for making the Scheme soon dried before I had an opportunity of nicely examining them. But since upon the dissection of a Viper I found that they † were continued along the Penis single, where the Penis was so; and afterwards divided, and did run to the end of each. Nor were there any vesiculae seminales or Prostates here to receive them; and a reason for it I shall alledge when I have have described the * Penes which here were very remarkable, not only for their structure, but number likewise, there being 4 in all, two on each side, which lay sheathed in the Body that upon first opening it they were not to be perceived, but only the large Orifices where they were drawn in as a finger of a Glove may be by a thread fastened to the end. But having protruded them by a Probe, they appeared as is represented in the Figure. And I did observe that toward the Basis, or Root, they were single of each side, and that here they were thick beset with prickles, whose points looked backwards, and were very sharp, and seemed, especially when dry, like the substance of the Bristles of a Hedge-hog: but hence they were divided, and did form two round bodys, of the bigness of a small Goose quill, about \(\frac{1}{2}\) of an Inch long of a red Colour, but the whole, as protruded, was above an Inch long. When protruded I found they could easily be retracted, and drawn in by the help of large Muscles, that were fastened to them and did run along under, and were at last inserted at the end of the Tayle at the setting on of the first Rattle; which upon the trial was so plain that we need not doubt of the use of them, and I shall therefore call them Retraeores Penum. But Charas seems to mistake them in Vipers, for the Penes themselves; which he describes to have their Origine from the extremity of the Tayle; as does Baldus Angelus Abbatius, Ulyss. Aldrovandus and others who it may be misled him in the account of these parts. Nor as to the other extremities are they more in the right, which by their Picture, and Description, they make to be altogether single, and covered and quick beset with Prickles like the Skin of a Porcupine. Whereas this part in Vipers too, as well as in the Rattle-Snake, divides and forms two large round bodys, or two distinct Penes. And this Baldus, or rather Camentius who made the dissection for him, seems to g De Viperarum natura & facultat. cap 19. pag. mibi 60. h Aldrovandus de Serpent. & Dragon. have observed where he saith, Quando turgidi fiunt, aut extra violenter emittantur, uti sese apud Paulum vidimus, Penes hanc formam referre aspectus aspero ut Erinaceus. For in Vipers they are Hispid to the end; but not in the Rattle-Snake, as is plainly represented in the figures of both. There are several Animals have no Penis at all, but Vasa deferentia, as most Fishes. All Quadrupeds that I know of have but a single one. Some Birds have but one. Most others if they may be said to have any have two but very short. In Crabs, Lobsters &c. there are two long ones, one on each side; but Earth-worms, Leeches, Shell-snails, &c. are Hermaphrodites, and have the perfect Organs of both Sexes. But where the Sex is single, the Rattle-Snake and that Family have these Organs of Generation the most numerous of any I have hitherto met with. But why the Male Rattle-Snake, or the Male Viper should have a Penis, when the Female has but two Uteri for receiving them, seems a difficulty to me. Amongst many Conjectures I have had about it, what seems the most to satisfy me, is this: That they have the Penis here on each side double, or forked, that so being enter'd the Uteri, by spreading themselves like the Pythagorean Y, they may the better and more firmly be retained there till they have performed their Duty. And this too seems one use of the Aculei or Bristles towards the Root of them; for having their points looking backwards when once they have enter'd the Pudendum, they must needs lock them in, and retain them there, till such time as the parts being tired, and subsiding, have leave to retreat. For in Animals which have no Vesiculae Seminales, 'tis requisite that the Coitus belong, that so the Seed which cannot quickly, may leisurely be transmitted from the Testes: but where 'tis before hand stored up in the Vesiculae, there the Coitus is soon over; but when they must expect the Generation, or at least a sluggish descent of it, Nature makes provision for the more convenient performing it. So in Dogs, which have no Vesiculae seminales seminalis, near the Root of the boney Penis there is a large body made up of an abundance of Cells and Vessels; which upon the rushing in of the blood, and spirits, is so mightily extended, and swelled, that it forcibly keeps him in, till such time as the Impetus be over, and the part subsides. So the Lump-fish, on its Breast has a large round body curiously contrived, like the tail of a Leech, or the Acetabulum of the Polypus; by which it can firmly adhere to the Female, and so by this means, tho its Penis be very short, yet be able to perform a Coitus. Cats, Lyons, &c. which have likewise very short Penes, that they may the better cling, are forced to make use of their Teeth, and Claws, and from the pain of these, not from the scalding of the Seed, come those fierce screcks, and hideous youlings. Therefore in our Rattle-snake, (where, as we have observed, there are no Vesiculae, and where the Vas deferens is all along crimped and winding; and so upon both accounts must be thought to be long in Coition) the contrivance, and structure of these parts seem very requisite. For altho in this action they twist their body, which may be some advantage too, yet not sufficient alone; for otherwise upon a little occasion the parts would be apt to slip out, which now they cannot, being forked, and hooked in too by the Aculei or Bristles. But the Deferentia being continued to the end of the Penis do likewise shew this must be the use of them. But that the Female may receive no injury by these Spines, Nature has made that part of the Uteri which they enter strong and gristly; as we observed in a Viper: and that the Male too might not be harmed by an over Extension of these parts, those strong Muscles which serve for retracting and drawing them in, do likewise secure them in this respect too. It may be likewise considered, since they are naturally so cold and frigid, whether these Aculei may not serve to incite them, and stir them up. But we shall pass off from these parts, that serve for increasing themselves, to those that often often prove the Destruction of Others, The Paysonous Teeth. But first I shall remark something of the other parts in the Mouth: as the Tongue, the Larynx, and the smaller Teeth: and in General, that the Head was but small, yet the Rictus was very large, but the Reason of it we shall give when we speak of the Bones. And as to The Tongue it was in all respects so like that of the Viz. fig. r.g. per., that the Description of the one may suit the other. 'Twas composed of two long round Bodys, contiguous and joyned together from the Root 3 of it's length; with great Agility they could dart them out, and retract them again; and that part which appeared out was of a black Colour, whereas that which lay sheathed within was Red; for 'twas fastened below the Throat, and thence was covered with a Vagina, or sheath, to the place where it issues out, which was near to the End of the Larynx; and for the better Ejaculation of it, the under Jaw too was here * divided, leaving a considerable space. For * Fig. s.j. if 'twere conjoyned as in other Animals and beset with Teeth, they would be apt to injure the Tongue; or at least it might prove incommodious to the use 'tis designed for, which in part I suspect with Charas to be for catching Flies, and such small Creatures they have a mind to devour. But Jo. Baptista Hodierna thinks 'tis rather for picking the dirt out of their Noses, which would be apt else to stuff them; since they are always grovelling on the Ground, or in Caverns of the Earth. Over the || Tongue did lye the Larynx; not formed with that variety of cartilages as is usual in other Animals; but so as to make a Rime or Slit for receiving or conveying out the Air. Now was there any Epiglottis for preventing other bodys from slipping in?; this being sufficiently provided for, by the strict closure of them: And the Air passing through only such a slit, without the contrivance i Apud Severinum in Pipersa Rutilica p. m. 254. of other parts for modulating it, can only make such a sound as we observe in their hissing. The Teeth are of 2 sorts,† 1. The lesser, which are seated in each Jaw, and serve for the catching, and retaining the food. 2. The Poisonous Fangs which kill it, and are placed without the Upper Jaw, are all Canini or Apprehensors; for since they do not chew or bruise their Food, but swallow all whole as they meet with it, there is no need of Molares. Of the first sort of Teeth: In the Lower Jaw there are two Rows on each side, 5 in a row, the Inward lesser than the Outward, so that there are here 20 in all: In the Upper Jaw there are but 16, 5 on each side placed backwards and 6 before. These do no harm, which was known to Mountebanks (as Cisalpinus and others observe) formerly; who to give a proof of the force of their Antidotes, would suffer themselves to be bitten by Vipers, but first took care to spoil them of their Fangs. These Fangs are placed without the Upper Fangs, towards the forepart of the mouth, nor fastened to the Maxilla, as the other Teeth; but the two outmost and largest Fangs were fixt to that Bone, which if any, may be thought to be the Ear Bone. The other Fangs I could not perceive were fastened to any Bone, but to Muscles or Tendons there. These Fangs or larger Teeth were not to be perceived upon first opening the Mouth, they lying couched under a strong Membrane or Sheath; but so as did make a large rising there on the out side of the Lesser Teeth of the Maxilla; but at pleasure when alive they could raise them to do execution with; not unlike as a Lyon or a Cat does its claws. These Teeth were hooked and bent like the Teeth of a Barbarossa; but some of the smaller of them were bent at Right Angles; but their shape and bigness will be best understood by the Figures we have made of them. On each side we met with about 6 or 7 not altogether placed so exact as is represented in the Head in the Scheme; which was done for the shewing shewing them more distinct. For the 2d Tooth, upon raising it, did lye more on the side of the first; and the other being fastened only to Muscles or Tendons which are flexible, 'tis difficult to assign them their posture. In all these Teeth, especially the larger, we took notice of a pretty large Foramen or Hole towards the Root of it, and towards the point there was a plain visible and large Slit, like the cut of a Pen sloping; and that part from the Slit to the Root was perfectly hollow; which first of all was discovered to us, by pressing gently with our finger the side of the Gumme; for then we did perceive that the Poyson did readily arise through the hollow of the Tooth, and issued out of the Slit. This we tryed several times; which tryals, as likewise our searching for all the Teeth wee could here find, did spoyle our Enquiry into the Baggs and the Glands that furnish them with that Liquor. But our defect herein may well be supplyed with what Mons. Charas and Sen. Redi have wrote of the same parts in Vipers. Nor do I think there may be any material difference as to these particulars in both Subjects. This poysonous Liquor I observed to be of a Water colour, lightly ringed Yellow; perhaps in some it may at sometimes be deeper: & this, it may be, has given occasion to that fond Opinion of those who have imagined that it was transmitted by a Vessel from the Gall bladder. Indeed scarce any Subject in Philosophy has admitted more controversy's than this of the Poyson of Vipers; in what it consists, what it is, and how it produces it's dire Effects. Severinus in his Vipera Pythia has made a large collection of them; and who so pleases may there satisfy their curiosity about it. But of late, famous has bin the contest between Sen. Redi, a Noble Italian, and Mr. Charas a French-man. 'Tis Redi's opinion, 'That the Yellow liquor contained k Vid. Fr. Redi obser. de Viperis ejusd. Epist. ad Aliquas oppositiones in suas Observat. Mr. Charas New Experim. upon Vipers. A Continuation of the new Experiments by Charas. in the Vesicles of the Gummes of the Vipers, is the only and true seat of the Poyson; That this Juice is not vene- mous, when taken in at the mouth, but that it is so, when let into wounds made by a Viper whilst she is alive, and even in those which she may be forced to make several daies after she is dead, provided the Yellow Liquor do intervene: That the same Liquor drawn from a live Viper, as well as that of a dead one, is alwaies Venemous, if let into the wound, and mingled with the blood of the Ani- mal wounded, whether it be used when liquid, or after it is dried, and reduced to a Powder: and that it kills all kind of Animals, into the wounds of which it shall have bin intromitted. But Mr. Charas wholly opposes this, and affirms, That the Poyson of a Viper is no where but in her enraged Spirits; That the Yellow Juice as wel of a live Viper, and even a next one, as of one that il either newly dead, or hath been so for several daies, cons tains in it no poyson at all; neither taken inwardly, nor in the bitting, nor put into the wound, nor mingled with the blood, nor any other way wherein it may be used: That it kills nor infects no kind of Animals, and that it is nothing but a meer innocent Saliva. Both insist upon Experiments for the proof of their own opinion, which be- ing sufficiently known, I shall not here repeat, or inter- pose in the Controversy, but, shall only offer that whereas Charas makes this Liquor to be a meer Saliva, and that it serveth not only to moisten the Ligaments, and to make them fit for the bending of the Teeth, but also to nourish them, and to make those grow that are there, as it were in a Nursery; and are, if we may so say, in ex- pectation to serve instead of the many Teeth, whether these come to fail in their force, or fall out of themselves. This I think is not so well asserted, the offices of the Sali- va being others; and it seems no way proper for Nourish- ment of the Teeth: nay, the Fabrick of the Teeth makes --- 1 New Experiments upon Vipers. p. 27. mibi. more for Senior Redi's opinion, they being thus hollow, and having that large slit towards the end, and this Juice so readily and naturally issuing through them; this seems to me to argue, that Nature designes it for other uses than Nourishment, for if so, by giving them so large a vent she would be frustrated of her end. But they being so sharp and strong at the ends, and the slit too plac'd towards the back, not inside of the Tooth; what can be more conveniently contriv'd both for making the wound and infunding the Poyson? For if the slit was inwards, by the strugling and withdrawing of the Animal assaulted, this slit would be apt to be stopt and occluded; and the descent of the poyson prevented; but being thus formed, it gives a greater advantage for its infusion. Thus the Scorpion, the Bee, the Emmet, nay the Sting of a Nettle, at the same time they make a wound, they leave behind them a drop of liquor, which excites those dreadful Symptoms; whereas the wound without it, would be inconsiderable. For Nierembergius, or rather Hernandez, from whom he transcribes the whole History of this Viper, tells us: Caninis in usu Medicos servatis pungunt Mexicanii Medici collum, cervicemque, doloris Capitis placandi gratia; but first I presume they clean them well from the Poyson, which more than the irritation of the Animal Spirits might otherwise endanger the exciting most dreadfull pains. I am confident in a Nettle there is not that irritation of Spirits and Fury, which yet to a considerable degree will (when assaulted) create pains and swellings; tho not so fatal as the other Poysons. For I am not yet so fully convinc'd (tho I have a just Deference for Mounsieur Charas, and a due regard for his laborious Researches and Inquiries) of his sentiment of the Innocence of this Liquor; and what has had some weight with me, is a Relation I m Hooks Micrographia. Obs. 25 p. 144. n Rerum med. Novae Hispan. Hist. l. 5. c. 17. p 328. Johnson de Serpent. l. 1. p. 27. lately had from an Intelligent and knowing Person; who informed me, That being in the Indies, there came to him, and his Company, an Indian with several sorts of Serpents, and offered to shew them some Experiments about the force of their Poyson, and the difference of them, and that this Practice is common with them: having therefore first pull'd out a large One, the Indian told him that this would do no harm; therefore making a Ligature on his Arm, as they do in letting blood, he exposed it naked to the Serpent, having first whipt and irritated him to make him bite it. The blood that came out of the wounds made by his Teeth he gather'd with his Finger, and laid it on his naked Thigh till he had got near a Spoonful. After this he takes out another call'd Cobras de Cabelo, which was lesser, and inlarges much upon the greatness of it's Poyson; and to shew them in part an Instance of it, grasping it about the Neck, he expresses out some of the Liquor in the Bags of the Gums about the Quantity, as he thought, of a graine, and this he puts to the coagulated Blood on his Thigh, which as soon as mixt with it straight put it into a great Fermentation, and working like Barme changed it into a Yellowish Liquor. The same has been likewise observed by others, and does seem to give us some light, how 'tis that this Poyson acts and confirms the known observation, that the biting of a Viper will cause the yellow Jaundice. A present Antidote for this Poyson is said to be the Snake stone, Pierre de Cobras de Cabelo 'tis called by the Portugueses, and is famous all over the Indies; 'tis described by Garcias ab Horato, by Kircher and others; particularly by P Senior Redi, who renders very much suspected the Relations that are commonly had of it's great force and Virtue; for in an abundance of Experiments which he made with it, he could never meet with any happy success: and altho the Tryal happened otherwise to Father Kircher in a Dog; and --- De le Boe Sylvij Frax. Med. l. c. 47. p. Fr. Redi Experimenta circa Res Nat. p. 5. &c. Caro. Charolus Magnini in a man at Rome where both did well; yet he ascribes it rather to the force of Nature, than the Stone, that was able stoutly to withstand and conquer the weak force of the Poyson. Indeed I must acknowledge the saying of Hippocrates to be true, Ἐμπειρίας ἐκφάνησις ἐξερευνητική, ἰδίωμα δυσκολότατον, and there is nothing more common, then imposing upon ourselves an Elenchus non Causa pro Causa. That it should always succeed, may as justly be questioned, as that it should always faile; and that it does not the latter, some Accounts I have had of Persons relieved by it here in England, make me think so. One instance is remarkable, that was told me by an Eminent Physician in London, of a Person near the Town that was bit by a Viper; his Hand and Arm soon swelled with great Extremity of Paine; but upon the Application of this Stone for one Night both were aswaged; and he thought himself well, and took of the Stone, which still did firmly adhere: but not long after his former symptoms violently returning, he had recourse to his Antidote, and then suffered it to continue there 'till it fell of itself, and so was cured. Other Tryals likewise the same Physician has made of it in different cases; and he thinks it has done him some service. One I shall mention, I formerly did myself, in a Patient troubled with the Gout in her Stomack, having removed it thence, it seized her Toe; but she being impatient of the Pain, that I might seem to do something, and to hinder her using abundance of Medicines, which every body was ready to advise her to, and might be apt to strike it to her Stomack again, I thought of this; holding the Stone therefore in my hand, and without acquainting her, I put it near the joyns where her pain was most; and being very near it, I perceived it move out of my hand, and readily adhere to the q Hip. Aphor. Sect. i. Aph. i. part. Soon after she acquainted me, that she very sensibly perceived a great drawing and trickling all down her Leg and Thigh; and afterwards owned an abatement of her Paine. In Pestilential Swellings very probably it may be of use. But I have already too far digressed and shall now go on in finishing my Account of the Anatome of the Rattle-snake in describing the Skeleton, and shall make amends for my former prolixness by being more concise and short in this. And first of the Bones of the Head. I observed that the * Cranium here was entire, without Sutures, as represented in our Figure: only where some other Bones were joyned to them, as forwards over the Nostrils, were two * Small Bones, to which were fastned the || Cartilages, or rather Bones which divide the Nose. The other Bones seemed admirably contrived for the great Extension, and widening of the Maxillae; which seems a great provision of Nature; for since it must swallow all things whole, and its Head is but small, without this most Mechanical contrivance it were impossible to do it. The Upper Jaw forward was joyned to the Bone that recieves the Poisonous Fang; and which had a large Cavity in it, which opened outward, and was thought to be the * Foramen of the Ear; but inwards we observed no perforation for a Nerve, unless there might be one that comes to it under that † Bone which conjoynes it to the Cranium. This Articulation seems advantageous, both for the motion of the Fang, which lyes sometimes couch'd, sometimes erected; as the Jaw too: but its principal and most remarkable advantage for Swallowing large bodies, is the curious Articulation of the Maxillae backwards to the Cranium, by two Bones, which from their use (since we know no Name to distinguish them by) we shall call Maxillarum Dilatores. Their shape, bigness, and aptness for this motion will readily enough be conceived by the Eye, in observing the Figure. || For the lower Jaw being not conjoined at the Mentum, as is usual in other Animals, but parted at a good distance; upon the receiving a large body, as the Membrane here to which they are fastened easily extends, so by lifting up, as also by bringing these two Bones more to a strait line, it must needs considerably widen the Rictus of the Mouth: and for this cause too they are made two, nor one, for performing this motion more easily. This Articulation * of the Dilatores (which is very curious) with the upper and lower jaw, makes those protuberances of the Head, which we liken'd to that of a Bearded Arrow, as do's the Poet, it may be upon the same account as well as its swiftness, where he saith *Rumpat & Serpens iter institutum, Si per obliquum similis Sagitte Terruit Mannos. The lower Jaw of each side was composed of two Bones, as appears in the Figure, but firmly conjoined. The fore Bone was for receiving the small teeth, the hinder towards the Articulation grew broad; as likewise did the Bone of the upper Jaw answerable to this place in the lower. But this upper Jaw towards the poisonous Fang divided into two Bones; One was fastened to the Bone of the poisonous Fang outwards; the other, which received the small teeth was inserted into the same Bone more inwards. The Vertebrae, according to the whole Figure of the body, were smallest towards both extremes, and largest in the middle. From the Neck to the Anus there were as many observed Scales on the Belly, viz. 168, but from the Anus to the setting on of the Rattle 29 more in number than the Scales. The former Vertebrae had a flat † upright Spine towards the back; and a slender * round oblique descending one inwards to the belly. To each Vertebra, besides those those Spines just mentioned, there were other * Proceffus's for the advantage of setting on of the Ribs, and the Articulation with one another; but what was most remarkable is (what I have already hinted) that round Ball in the lower part of the upper Vertebra, which enters a socket of the upper part of the lower Vertebra, like as the head of the Os Femoris does the Acetabulum of the Os Ischii; by which contrivance, as also the Articulation with one another, they have that free motion of winding their bodies any ways. The Ribs in the Neck were small, but larger towards the middle of the body, where they were about 2 Inches long; but towards the Tail they grew lesser and shorter again; and did all terminate at the beginning of the Scales of the belly. In the Vertebrae of the Tail inwards there were two* Spines, whereas in the other Vertebrae there was but One, as likewise therewere here transverse slender||Proceffus's something analogous to Ribs. To the last Vertebra of the Tail was fastened the * Rattle; in our Subject there was but 5, but some others seemed to be broken off. That next the Taile was of a lead-colours; the others of a cinericeous. 'Tis well described by * Dr. Grew, who says: 'They are very hollow, thin, hard, and dry bones; and therefore very brittle, almost like glass; and very sonorous. They are all very near of the same bulk, and of the self same figure; most like the Os sacrum of a man: for altho the last of them only seems to have a rigid Taile, or Epiphysis adjoyned to it, yet have every one of them the like; so as the Taile of every uppermost bone runs within two of the bones below it; by which artifice they have not only a moveable coherence, but also make a more multiplied sound; each bone hitting against two others at the same time. The use of this Rattle (since I know no other) I shall give in the words of r Gulielm. Piso, who tells us; Huic tam pernicioso Colubro, benigna natura cautionis quasi gratia. titia crepitaculum addidisse videtur; ut illius Sonitu admonitus quislibet homo non solum, sed & quaecunque Pecus, vel Jumentum, tempestive sibi caveat a vicino Hoste. But why he should make it so dangerous, if thrust into a man's Fundament (which how it can I don't well see) as to be more fatal than the poison of his Teeth; I know no reason. Both he and Nierembergius and others do assert, that every year there is an addition of a new Rattle, which Dr. Grew suspects, for then he must live 16 years, for so many joints there are observed in some in our Repository; I have been told in some there have been above 20. These Rattles are placed with their broadest part perpendicular to the body, not Horizontal. And the i. is fastened to the last Vertebra of the Tail by means of a thick * Muscle under it, and by the membranes that conjoin it to the Skin. I have not given the figure of the whole Skeleton, since what is wanting may be sufficiently understood by the description; and who so pleases may view the Skeleton itself, in the Repository of the Royal Society, very curiously prepared by that ingenious young Gentleman Rich. Waller Esq; a worthy Member of the Society, whose great assistance to me, I must hear gratefully acknowledge; as to the Designs, and otherwise: his curious Pen still illustrating what my Pen was often less able to describe. \[ \text{Guii. Piso de India utriusque re Nat. & med. l. 5. c. 2. p. 374} \] THE EXPLANATION OF THE FIGURES. FIGURE I. Represents that part of the body opened, which containes the Lungs, the Heart, the Gullet, Stomack, &c. a a a The Arteria aspera, or Windpipe. B The upper part of the Lungs, which is Vesiculous. c c c c c The lower part of the Lungs, which makes a large Bladder. d The first Swelling Oesophagus, or false stomack. e e e The Oesophagus or Gullet, and that part of it, where'tis straiter. f The second Swelling of the Oesophagus, or second false stomack. g The true Stomack. h i k l A short straightening of the Gut, a little below the Pylorus. The Intestines. The Heart. The Auricle. m m m Three Arteries, whereof there are Two Ascending, and One Descending. n n n Three large Veins, whereof two are descending, and the third ascending, which last does seem to divide the Liver into two Lobes. o o The Liver. p The Gall-bladder. q The Spleen, as 'tis call'd by the Antients; but by Charas the Pancreas. A large Blood-vessel, that runs in the midst of the Scales of the belly. The Muscles belonging to the Scales of the belly. FIGURE II. Shews those parts, that are contained in the lower part of the body. a The Intestines cut off just below the Pylorus. b The Gall-bladder. c The Ductus Bilarius, that passes through the middle of the Spleen, or as call'd by Charas, the Pancreas; and enters the large Gut. d The Spleen, or Pancreas. e The Intestines which was very large and winding but short. f The Rectum. g The Anus. h The Testes. i The Vasa Deferentia. k The Penes on each side, which first at the Root are conjoined and are thick be set with Bristles. l The Muscles that serve for the drawing in the Penes. m The Sent. baggs. n A large Blood-vessel that runs on one side of the left Kidney. o The Emulgent that arise from the same. p The Secretory vessels. q The large Blood-vessels of the right Kidney. r The Emulgent arising from it. s A round body of Blood-vessels. t Secretory vessels. u The Ureters. FIGURE III. Represents the Penes of one side of a Viper. The Vas deferens, which afterwards divides, and runs to the end of the Penes. The Penes. The Muscles which retract the Penes in. FIGURE IV. Represents part of the Lungs opened by the Trachea. aaaaa. The Ateria Aspera, divided in the middle. bbb. Some larger branches of Blood vessels. ccc. The Vesiculae, or cells of the Lungs. FIGURE V. Exhibits the Head of the Rattle-Snake, with its mouth opened to shew his Teeth, and other parts there. a. The hole of the Nostril. b. The Foramen which leads to a large Cavity, which has no Perforation for any Nerve inwards, but yet tis thought to be for hearing. c c. The small Teeth in the upper Jaw. d d. The large Fangs, or poisonous Teeth. eee. The place where the Bladders of Poison lyce. f. The Larynx. g. The forked Tongue. h. The Teeth in the lower Jaw. i. The place where the lower Jaw is divided at the Mentum. FIGURE VI. Represents the Scull. a. The Cranium without any sutures. bb. The Orbits of the Eyes. cc. Two small bones over the Nose. d. The Gristy or rather Boney Sepimentum of the Nose. ee. A small Bone, that lies between the Cranium, and that bone, in which is fixt the Poisonous Fang. ff. A Cavity in that Bone, to which is fastened the poisonous Fang, whose Outward Orifice is represented in the Fifth Figure by the letter (b) and is thought to be the Ear. g. The large Poisonous Fang, which is fastened to the Ear-bone. h. The Other Poisonous Teeth, which are not fixt in the bone but to Muscles. ii. The Upper Maxilla, which contains the small Teeth. kk. One side of the lower Maxilla, with its double row of teeth, which in the middle seems to be joined by a future. l. The Distance at the Mentum, between the two sides of the lower Maxilla or Jaw. Where the two Maxillæ are joined together backwards, and by a Tendon are fastened to another Bone, which from its use, and for distinction sake; we call Dilatores Maxillarum. The Dilatores of the Jaws. A short bone which joynes the Dilator's to the Scull or Cranium. The Vertebræ of the Neck. **FIGURE VII.** Represents the Poisonous teeth. **FIGURE VIII.** Shews one of the Vertebræ of the Back. a. The Outward spine of the Vertebræ, which is flat longways. b. The Inward Spine of the Vertebræ, which is round. c. A large flat Processus, for the Articulation of the Vertebræ. d. Small transverse Processus's for the setting on the Ribs. e. Around ball, like the head of the Os Femoris, which enters a socket of the lower Vertebra, as that do's the Acetabulum of the Os Ischij. **FIGURE IX.** Shews one of the Vertebræ of the Tail. a. The spine towards the Back. b. The two inward spines. c. The transverse Spines, Analogous to Ribbs. **FIGURE X.** Represents the Vertebræ of the Tail and the muscular flesh which fastens the first Rattle. a. The Vertebræ. b. The Muscle on which is fastened the Rattle. **FIGURE XI.** Exhibits a single Rattle, which has three Joyns: the first and largest appears when conjoined with Others; the two other serve for the fastening on the succeeding Rattles, and are covered by them. **FIGURE XII.** Shews the five Rattles as joined together.