Fabricius gives this reason for some animals being oviparous, for all not producing living offspring: “It is,” he says, “that eggs detained in the uterus till they had produced their chicks would interfere with the flight of birds, and weigh themdown by their weight. Serpents would also be hindered in their alternate zig-zag movements by a multitude of eggs in the abdomen. In the body of tortoises, with their hard and girding shell, there is no room for any store or increase of eggs; nor would the abdomen of fishes suffice for the multitude of eggs they must spawn were these to grow to any size. It was, therefore, matter of necessity that those creatures should lay their eggs imperfect. It seems most natural that an animal should retain and cherish its conception in its interior until the fœtus it produces has come to maturity; but nature sees herself compelled, as it were, occasionally to permit the premature birth of various eggs, and to provide them, without the body of the parent, with the nourishment they require for their complete development. As to everything that refers to the evolution of the fœtus, all animals are engendered from an oviform primordium; I say oviform, not as meaning that it has the precise configuration of an egg, but the nature and constitution of one; this being common in generation, that the vegetal primordium whence the fœtus is produced, including the nature of an egg, corresponding in its proportions to the seed of a plant, pre-exists. In all vegetal primordia, consequently, whether eggs, or having the form of eggs, there are inherent the nature and conditions of an egg, properties which the seeds of plants have in common with the eggs of animals. The primordium of any animal, whatsoever, is therefore called seed and fruit; and in like manner the seed of every plant is spoken of as a kind of conception or egg.”
And this is the reason why Aristotle says:[334]“Animals that engender internally have something formed in the fashion of an egg after their first conception: there is a fluid contained within a delicate membrane, like an egg without the shell. And this is the cause why the disorders of the conception, which are apt to occur in the early period, are called discharges.” Such a discharge is particularly observed among women when they miscarry in the course of the first or second month. I have repeatedly seen such ova aborted at this time; and such was the one which Hippocrates has described as having been thrown off by the female pipe-player in consequence of a fall.
In the uterus of all animals there is consequently present a prime conception or primordium, which, on Aristotle’s testimony,[335]“is like an egg surrounded with a membrane from which the shell had been removed.” This fact will appear still more plainly from what is about to be said. Meantime let us conclude with the philosopher, “that all living creatures, whether they swim, or walk, or fly, and whether they come into the world with the form of an animal or of an egg, are engendered in the same manner.”
The generation of viviparous animals in general is illustrated from the history of that of the hind and doe, and the reason of this selection.
It was customary with his Serene Majesty, King Charles, after he had come to man’s estate, to take the diversion of hunting almost every week, both for the sake of finding relaxation from graver cares, and for his health; the chase was principally the buck and doe, and no prince in the world had greater herds of deer, either wandering in freedom through the wilds and forests, or kept in parks and chases for this purpose. The game during the three summer months was the buck, then fat and in season; and in the autumn and winter, for the same length of time, the doe. This gave me an opportunity of dissecting numbers of these animals almost every day during the whole of the season when they were rutting, taking the male, and falling with young; I had occasion, so often as I desired it, to examine and study all the parts, particularly those dedicated to the offices of generation.
I shall therefore consider the generation of viviparous animals in general, from the particular history of the hind and doe, as the instance most convenient to me; and as I have done above, in speaking of oviparous generation, where I have referred everything to the common fowl, so shall I here, in discussing viviparous generation, refer all to the fallow deer and roe. In taking this course, I am not moved by the same reasons as I was in reference to the hen’s egg; but because the great prince, whose physician I was, besides taking much pleasure in such inquiries, and not disdaining to bear witness to my discoveries, was pleased in his kindness and munificence to order me an abundant supply of these animals and repeated opportunities of examining their bodies.
I therefore propose to give the history of generation in the hind and doe as I have observed it during a long series of years, and as most familiar to me, believing that from thence something certain in reference to the generation of other viviparous animals may be concluded. In giving a faithful narrative of this history, I shall not abstain in its course from introducing particulars worthy of note that have either been observed accidentally and by the way, or that are the result of particular dissections instituted for the purpose of arriving at conclusions, the subjects of these having been other bisulcated, hoofed, or multungulated animals, or, finally, man himself. We shall give a simple narrative of the series of formations of the fœtus, following the footsteps of nature in the process.
Of the uterus of the hind and doe.
About to treat of the generation of the hind and doe, our first business will be to speak of the place where it proceeds, or of the uterus, as we have done above, in giving the history of the common fowl, by which all that follows will be more easily and readily understood. And history has this great pre-eminence over fable, that it narrates the events which transpired in certain places at certain times, and therefore leads us to knowledge by a safe and assured way.
Now that we may have a clearer idea of the uterus of the hind, I shall describe both its external and internal structure, following the uterus of the human female as my guide. For man is the most consummate of creatures, and has thereforethe genital as well as all other parts in higher perfection than any other animal. The parts of the female uterus consequently present themselves with great distinctness, and by reason of the industry of anatomists in this direction are believed to be particularly well known to us.
We meet with many things in the uterus of deer which we encounter in the uterus of the human female; and we also observe several that differ. In the vulva or os externum we find neither labia, nor clitoris, nor nymphæ, but only two openings, one for the urine, adjacent to the pecten, or os pubis, the other the vagina, lying between the meatus urinarius and the anus. A cuticular or membranous fold, such as we have noted in the hen, stretching downwards from the anus, acts as a velabrum, supplies the place of nymphæ and labia pudendi, and guards against injury from without. This velabrum must be somewhat retracted by the female when she copulates, or at all events must be raised by the penis of the male as it enters the vulva.
The symphysis pubis being divided in deer, and the legs widely separated, the urinary bladder, the vagina which is entered by the penis of the buck, and the cervix uteri, are all seen in their relative situations, not otherwise than they are in women; the ligamenta suspensoria, with the veins, arteries, and testicles, as they are called, also come into sight; the cornua of the uterus in these creatures are also more remarkable than any other part of this organ.
As for the vessels called vasa præparantia and vasa deferentia seu ejaculantia, you will discover nothing of the kind here, nor indeed in any other female animal that I am aware of. The anatomists who believe that women emit a seminal fluid sub coitu have been too eager in their search after such vessels; for in some they are not met with at all, and where they do occur they never present themselves with anything of uniformity of character. Wherefore it seems most likely that women do not emit any semen sub coitu, which is in conformity as I have said with what the greater number of women state. And although some of warmer temperament shed a fluid in the sexual embrace, still that this is fruitful semen, or is a necessary requisite to conception, I do not believe; for many women conceive without having any emission of the kind, and some evenwithout any kind of pleasurable sensation whatsoever. But of these things more in another place.
The vulva, or vagina uteri, which extends from the os externum to the inner orifice of the uterus, is situated in the hind, as well as in the human female, between the urinary bladder and the intestinum rectum, and corresponds in length, width, and general dimensions, with the penis of the male. When this part is laid open it is found occupied lengthwise by rugæ and furrows, admitting of ready distension, and lubricated with a sluggish fluid. At its bottom we observe a very narrow and small orifice, the commencement of the cervix uteri, by which whatever is propelled outwards from the cavity of the uterus must pass. This is the corresponding orifice to that which medical men assert is so firmly closed and sealed up in the pregnant woman and virgin, that it will not even admit the point of a probe or fine needle.
The os uteri is followed by the cervix or process, which is much longer and rounder than in woman, and also more fibrous, thicker, and nervous; it extends from the bottom of the vagina to the body of the uterus. If this cervix uteri be divided longitudinally, you perceive not only its external orifice at the bottom of the vagina, its surface in close contact, and so firmly agglutinated that not even air blown into the vagina will penetrate the cavity of the uterus, but five other similar constrictions placed in regular order, firmly contracted against the entrance of any foreign body and sealed with gelatinous mucus; just as we find the narrow orifice of the woman’s uterus plugged with a yellowish glutinous mass. A like constriction of parts, all firmly closed, and precluding all possibility of entrance, Fabricius has found in the uterine neck of the sheep, sow, and goat. In the deer there are very distinctly five of these constrictions, or so many orifices of the uterus constricted and conglutinated, which may all justly be looked upon as so many barriers against the entrance of anything from without. Such particular care has nature taken, that if the first barrier were forced by any cause or violence, the second should still stand good, and so the third, and the fourth, and the fifth, determined apparently that nothing should enter. A probe pushed from within outwards, however, from the cavity of the uterus towards the vagina, passes through readily. A way had to beleft open for the escape of flatus, menstrual blood, and other excreted fluids; but even the smallest and most subtile things, air, for instance, and the seminal fluid are precluded all access from without.
In all animals this uterine orifice is found obstructed or plugged up in the same way as it is wont to be in women, among whom we have sometimes known the outlet so much constricted that the menses, lochia, and other humours were retained in the womb, and became the exciting cause of most severe hysterical symptoms. In such cases it became necessary to contrive a suitable instrument with which the os uteri being opened, the matters that stagnated within were discharged, when all the accidents disappeared. By this contrivance injections could also be thrown into the cavity of the uterus, and by means of these I have cured internal ulcers of the womb, and have occasionally even found a remedy for barrenness.
The cavity of the uterus in the deer is extremely small, and the thickness of its walls not great; the body of the womb in these animals is, in fact, but a kind of vestibule, or ante-room, in the cavity of which a passage opens to the right and left into either cornu.
For the parts are different in almost all animals from what they are in woman, in whom the principal part of the uterus is its body, and the cervix and cornua are mere appendices, that scarcely attract attention. The neck is short; the cornua are slender round processes extending from the fundus uteri like a couple of tubes, which anatomists indeed commonly speak of as the vasa ejaculatoria. In the deer, however, as in all other quadrupeds, except the ape and the solipeds, the chief organ of generation is not the body but the horns of the uterus. In the human female and the solipedia, the uterus is the ‘place’ of conception, in all the rest the conception is perfected in the cornua; and this is the reason why writers so commonly speak of the cornua uteri in the lower animals under the simple name of the uterus, saying that the uterus in certain animals is bipartite, whilst in others it is not, understanding by the word uterus the place in which conception takes place, this in the majority of viviparous and especially of multiparous animals being the cornua, to which moreover all the arteries and veins distributed to the organs of generation are sent. We shall therefore, in treatingof the history of generation in the deer employ the words uterus and horns of the uterus promiscuously.
In the human female, as I have said, the two tubes that arise near the cervix uteri and there perforate its cavity have no analogy to the parts generally called cornua, but, on the contrary, in the mind of some anatomists, to the vasa spermatica. By others again they are called the spiramenta uteri—the breathing tubes of the uterus; and by others still they are called the vasa deferentia seu reservantia, as if they were of the same nature as the canals so designated in the male; whilst they in fact correspond to the cornua of the uterus in other animals, as most clearly appears from their situation, connexion, length, perforation, general resemblance, and also office. For as many of the lower animals regularly conceive in the cornua uteri, so do women occasionally carry their conceptions in the cornu, or this tube, as the learned Riolanus[336]has shown from the observations of others, and as we ourselves have found it with our own eyes.
These cornua terminate in a common cavity which, as stated, forms a kind of porch or vestibule to the uterus, and corresponds in the deer to the neck of the womb in women; in the same way as the tubes in question in the human female correspond to the cornua uteri in the deer. Now this name of cornua has been derived from the resemblance of the parts to the horns of an animal; and in the same way as the horns of a goat or ram are ample at the base, arched and protuberant in front, and bent-in behind, so are these horns of the uterus in the hind and doe capacious inferiorly, and taper gradually off superiorly, as they are reflected towards the spine. Further, as the horns of the animal are unequally tuberculated and uneven in front, but smooth behind, so are the horns of the uterus tuberculated, as it were, and uneven, through the presence of cells, something like those of the colon, inferiorly and anteriorly; but superiorly, and on the aspect towards the spine, they are continuous and smooth, and present themselves secured and bound down by a ligamentous band; they at the same time gradually decrease in size like horns. Did one take a piece of empty intestine, such as is used for making sausages, and drawing a tape through it, tied this on one side, he would have it puckered and constricted on that side, and thrown into cells similar to those of the colon on the opposite side. Such is the structure of the cornua of the uterus in the hind and doe. In other animals it is different; for there the cells are either much larger, or they are entirely wanting. The cells of the cornua uteri of the hind and doe, however, are not all of the same size; the first that is met with is much larger than any of the others; and here it is that the conception is generally lodged.
As the uterus, tubes, or cornua, and other parts appertaining in the human female are connected with the pubes, spine, and surrounding structures by the medium of broad and fleshy membranes, by suspensory bands, as it were, which anatomists have designated by the name of bats’ wings, because they have found that the uterus suspended in this way resembled a bat with its wings expanded, so also are the cornua uteri, together with the testes [ovaries], on either side, and all the uterine vessels, connected with the neighbouring parts, particularly with the spine, by means of a firm membrane, within the folds of which are suspended all the parts that have been mentioned, and which serves the same office with reference to these uterine structures as the mesentery does to the intestines, and the mesometrium to the uterus of the fowl. In the same way, too, as the mesenteric arteries and veins are distributed to the intestines through the mesentery, are the uterine vessels distributed to the uterus through the membrane in question; in which also certain vessels and glands are perceived on either side, which by anatomists are generally designated the testicles [the ovaries.]
The substance of the horns of the uterus in the hind and doe is skinny or fleshy, like the coats of the intestines, and has a few very minute veins ramified over it. This substance you may in anatomical fashion divide into several layers, and note different courses of its component fibres, fitting them to perform the several motions and actions required, retention, namely, and expulsion. I have myself frequently seen these cornua moving like earthworms, or in the manner in which the intestines may at any time be observed, twisting themselves with an undulatory motion, on laying open the abdomen of a recently slaughtered animal, by which they move on the chyleand excrements to inferior portions of the gut, as if they were surrounded and compressed with a ring forced over them, or were stripped between the fingers.
The uterine veins, as in woman, all arise from the vena cava, near the emulgents; the arteries (and this also is common to the deer and the human subject) arise from the crural branches of the descending aorta. And as in the pregnant woman the uterine vessels are relatively larger and more numerous than in any other part of the body, this is likewise the case in the pregnant hind and doe. The arteries, however, contrary to the arrangement in other parts of the body, are much more numerous than the veins; and air blown into them makes its way into the neighbouring veins, although the arteries cannot be inflated in their turn by blowing into the veins. This fact I also find mentioned by Master Riolanus; and it is a cogent argument for the circulation of the blood discovered by me; for he clearly proves that whilst there is a passage from the arteries into the veins, there is none backwards from the veins into the arteries. The arteries are more numerous than the veins, because a large supply of nourishment being required for the fœtus, it is only what is left unused that has to be returned by the latter channels.
In the deer as well as in the sheep, goat, and bisulcate animals generally, we find testicles; but these are mere little glands, which rather correspond in their proportions to the prostate or mesenteric glands, the use of which is to establish divarications for the veins, and to store up a fluid for lubricating the parts, than for secreting semen, concocting it into fecundity, and shedding it at the time of intercourse. I am myself especially moved to adopt this opinion, as well by numerous reasons which will be adduced elsewhere, as by the fact that in the rutting season, when the testes of the buck and hart enlarge and are replete with semen, and the cornua of the uterus of the hind and doe are greatly changed, the female testicles, as they are called, whether they be examined before or after intercourse, neither swell nor vary from their usual condition; they show no trace of being of the slightest use either in the business of intercourse or in that of generation.
It is surprising what a quantity of seminal fluid is found in the vesiculæ seminales and testicles of moles and the largerkinds of mice at the season of intercourse; this circumstance corresponds with what we have already noticed in the cock, and the great change perceptible in the organs of generation of both sexes; nevertheless, the glands, which are regarded as the female testes, continue all the while unchanged and without departure from their pristine appearance.
All that has now been said of the uterus and its horns in hinds and does applies in major part to viviparous animals in general, but not to the human female, inasmuch as she conceives in the body of the uterus, but all these, with the exception of the horse and ass, in the horns of the organ; and even the horse and ass, although they appear to carry their fruit in the uterus, still is theplaceof the conception in them rather of the nature of an uterine horn than the uterine body. For theplacehere is not bipartite indeed, but it is oblong, and different from the human uterus both in its situation, connexions, structure, and substance; it bears a greater affinity to the superior uterus or uterine process of the fowl, where the egg grows and becomes surrounded with the albumen, than to the uterus of the woman.
Of the intercourse of the hind and doe.
So much for the account of the uterus of the female deer, where we have spoken briefly upon all that seemed necessary to the history of generation, viz. the ‘place’ of conception, and the parts instituted for its sake. We have still to speak of the action and office of this ‘place,’ in other words, of intercourse and conception.
The hind and doe admit the male at one and only one particular season of the year, namely, in the middle of September, after the Feast of the Holy Cross; and they bring forth after the middle of June, about the Feast of St. John the Baptist (24th June). They, therefore, go with young about nine months, not eight, as Pliny says;[337]with us, at all events,they produce in the ninth month after they have taken the buck.
At the rutting season the bucks herd with the does; at other times they keep severally apart, the males, particularly the older ones, associating together, and the females and younger males trooping and feeding in company. The rutting season lasts for a whole month, and it begins later if the weather have been dry, earlier if it have been wet. In Spain, as I am informed, the deer are hardly in rut before the beginning of October, wet weather not usually setting in there until this time; but with us the rutting season rarely continues beyond the middle of October.
At this time deer are rendered savage by desire, so that they will attack both dogs and men, although at other seasons they are so timid and peaceable, and immediately betake themselves to flight on the barking of even the smallest dog.
Every male knows all his own females, nor will he suffer any one of them to wander from his herd: with a run he speedily drives back any straggler; he walks jealously from time to time among his wives; looks circumspectly about him, and the careful guardian of his own, he shows himself the watchful sentinel. If a strange doe commit any offence, he does not pursue her very eagerly, but rather suffers her to get away; but if another buck approach he instantly runs to meet him, and gives him battle with his antlers.
The hind and doe are held among the number of the chaster animals; they suffer the addresses of the male reluctantly, who, like the bull, mounts with violence, and unless forced or tired out, they resist him; which disinclination of the females appears also to be the reason of their herding together, and confining themselves to their own males, who are always the older and better armed; for when any strange male approaches them they immediately take to flight, and seek refuge in their own herd, and protection to their chastity, as it seems, from their proper husband.
If a younger male finds a female straying alone, he immediately pursues her, and when she is worn out and unable to fly farther he mounts and forces her to his pleasure.
The males all provide themselves what are called rutting places; that is to say, they dig a trench, or they take theirstand upon an acclivity, whither they compel their females to come in turn. The female that is to be leapt stands with her hind feet in the trench prepared for the purpose, stooping or lowering her haunches somewhat, if need be; by which the male is enabled, pressing forward upon her in the same way as a bull, to strike her, in technical language, and finish the business of copulation at one assault.
Old and sturdy bucks have a considerable number of does in their herds, as many as ten, and even fifteen; younger and weaker males have fewer. Keepers say that the doe is sated with two, or at most with three leaps; once she has conceived she admits the male no more.
The lust of the male cools when he has served his females; he becomes shyer, and much leaner; he deserts his herd and roams alone, and feeds greedily to repair his wasted strength, nor does he afterwards approach a female for a whole year.
When the male is capable of intercourse the hair on his throat and neck grows black, and the extremity of the prepuce becomes of the same colour, and stinks abominably. The females take the male but rarely, and only in the night or in dusky places, which are, therefore, always chosen by the males for their connubial pleasures. When two stags engage in battle, as frequently happens, the vanquished yields possession of his females to the victor.
Of the constitution or change that takes place in the uterus of the deer in the course of the month of September.
We now come to the changes that take place in the genital parts of the female after intercourse, and to the conception itself. In the month of September, then, when the female deer first comes in season, her cornua uteri, uterus, or place of conception, grows somewhat more fleshy and thick, softer also, and more tender. In the interior of either cornu, at that part, namely, which looks drawn together by a band, and is turned towards the spine, we observe, protruding in regular succession, five caruncles, soft warts, or papillæ. The first of these is larger than any of the others, and each in succession is smaller than the one before it, just as the cornua themselves become smaller and smaller towards their termination. Some of the caruncles grow to the thickness of the largest finger, and look like proud flesh; some are white, others of a deeper red.
From the 26th to the 28th of September, and also subsequently, in the month of October, the uterus becomes thicker, and the carunculæ mentioned come to resemble the nipples of the woman’s breast: you might fancy them ready to pour out milk. Having removed their apex that I might examine their internal structure, I found them made up of innumerable white points compacted together, like so many bristles erect, and connected by means of a certain mucous viscidity; compressed between the fore finger and thumb, from the base upwards, a minute drop of blood oozed out from each point, a fact which led me, after farther investigation, to conclude that they were entirely made up of the capillary branches of arteries.
During the season of intercourse, therefore, the uterine vessels, particularly the arteries, are observed to be more numerous and of larger size; although the parts called the female testes, as I have said above, are neither larger nor more highly gorged with blood than before, and do not appear to be altered in any way from their former state.
The inner aspect of the uterus or cornua uteri, where it is puckered into cells, is as smooth and soft as the ventricles of the brain, or the glans penis within the prepuce. Nothing, however, can be discovered there—neither the semen of the male, nor aught else having reference to the conception—during the whole of the months of September and October, although I have instituted repeated dissections with a view of examining the conception at this period. The males have been doing their duty all the while; nevertheless, reiterated dissection shows nothing. This is the conclusion to which I have come, after many years of observation. I have only occasionally found the five caruncles so close together that they formed a kind of continuous protuberance into the interior of the uterus. But when, after repeated inspections, I still found nothing more in the uterus, I began to doubt, and to askmyself whether the semen of the male could by any possibility make its way—by attraction or injection—to the seat of the conception? And repeated examination led me to the conclusion that none of the semen whatsoever reached this seat.
Of what takes place in the month of October.
Repeated dissections performed in the course of the month of October, both before the rutting season was over and after it had passed, never enabled me to discover any blood or semen, or a trace of anything else, either in the body of the uterus or in its cornua. The uterus was only a little larger, and somewhat thicker; and the caruncles were more tumid and florid, and, when strongly pressed with the finger, discharged small drops of blood, much in the manner in which a little watery milk can be squeezed from the nipples of a woman in the fourth month of her pregnancy. In one or two does, indeed, I found a green and ichorous matter, like an abscess, filling the cavity of the uterus, which was preternaturally extenuated; in other respects these animals were healthy, and in as good condition as others which I examined at the same time.
Towards the end of October and beginning of November, the rutting season being now ended, and the females separating themselves from the males, the uterus begins (in some sooner, in others later) to shrink in size, and the walls of its internal cavity, inflated in appearance, to bulge out; for where the cells existed formerly there are now certain globular masses projecting internally, which nearly fill the whole cavity, by which the sides are brought into mutual contact, and almost agglutinated, as it seems, so that there is no interval between them. Even as we have seen the lips of boys who, in robbing a hive, had been stung in the mouth, swollen and enlarged, so that the oral aperture was much contracted, even so does the internal surface of the uterus in the doe enlarge, and become filled with a soft and pulpy substance, like the matter of the brain,that fills its cavity and involves the caruncles, which, though not larger than before, look whiter, and as if they had been steeped in hot water, much as the nurse’s nipple appears immediately after the infant has quitted it. And now I have not found it possible by any compression to force blood out of the caruncles as before.
Nothing can be softer, smoother, more delicate, than the inner aspect of the uterus thus raised into tubers. It rivals the ventricles of the brain in softness, so that without the information of the eye we should scarcely perceive by the finger that we were touching anything. When the abdomen is laid open immediately after the death of the animal, I have frequently seen the uterus affected with a wavy and creeping motion, such as is perceived in the lower part of a slug or snail whilst it is moving, as if the uterus were an animal within an animal, and possessed a proper and independent motion. I have frequently observed a movement of the same kind as that just described in the intestines, whilst engaged in vivisections; and indeed such a motion can both be seen and felt in the bodies of dogs and rabbits whilst they are alive and uninjured. I have also observed a corresponding motion in the testes and scrotum of men; and I have even known women upon whom, in their eagerness for offspring, such palpitations have imposed. But whether the uterus in hysterical females, by ascending, descending, and twisting, experiences any such motion or not, I cannot take upon me to declare; and whether the brain, in its actions and conceptions, moves in anything of a similar manner or not, though a point difficult of investigation, I am inclined to look upon as one by no means unworthy of being attempted.
Shortly afterwards, the tubercular elevations of the inner surface of the uterus that have been mentioned begin to shrink; it is as if, losing a quantity of moisture, they became less plump. In some instances; indeed, though rarely, I have observed something like purulent matter adhering to them, such as is usually seen on the surface of wounds and ulcers when they are digested, as it is said, they pour out smooth and homogeneous pus. When I first saw this matter, I doubted whether it was the semen of the male or not, or a substance concocted from its purer portion. But as it wasonly in exceedingly rare instances that I met with such matter, and as twenty days had then passed since the doe had had any intercourse with the buck, and farther, as the matter was not viscid and tenacious, or spumous, such as the seminal fluid presents itself to us, but rather friable, purulent looking, and inclining to yellow, I came to the conclusion that it was the effect of accident, a sweat or exudation in consequence of violent exercise previous to death; just as in a catarrh the thinner defluxion of the nose is by and by changed into a thicker mucus.
Having frequently shown this alteration in the uterus to his majesty the king as the first indication of pregnancy, and satisfied him at the same time that there was nothing in the shape of semen or conception to be found in the cavity of the organ, and he had spoken of this as an extraordinary fact to several about him, a discussion at length arose: the keepers and huntsmen asserted at first that it was but an argument of a tardy conception occasioned by the want of rain. But by and by, when they saw the rutting season pass away, I still continuing to maintain that things were in the same state, they began to say that I was both deceived myself and had misled the king, and that there must of necessity be something of the conception to be found in the uterus. These men, however, when I got them to bring their own eyes to the inquiry, soon gave up the point. The physicians, nevertheless, held it among their αδύνατα—their impossibilities—that any conception should ever be formed without the presence of the semen masculinum, or some trace remaining of a fertile intercourse within the cavity of the womb.
That this important question might be the more satisfactorily settled in all time to come, his highness the king ordered about a dozen does to be separated from the bucks towards the beginning of October, and secluded in the inclosure, which is called the course, at Hampton Court, because the animal placed there has no means of escape from the dogs let loose upon it. Now that no one might say the animals thus secluded retained any of the semen received from the last connexions with the male, I dissected several of them before the rutting season had passed, and ascertained that no seminal fluid remained in the uterus, although the others were found to bepregnant in consequence of the preceding intercourse—impregnated by a kind of contagion as it appears—and duly produced their fawns at the proper time.
In the dog, rabbit, and several other animals, I have found nothing in the uterus for several days after intercourse. I therefore regard it as demonstrated that after fertile intercourse among viviparous as well as oviparous animals, there are no remains in the uterus either of the semen of the male or female emitted in the act, nothing produced by any mixture of these two fluids, as medical writers maintain, nothing of the menstrual blood present as ‘matter’ in the way Aristotle will have it; in a word, that there is not necessarily even a trace of the conception to be seen immediately after a fruitful union of the sexes. It is not true, consequently, that in a prolific connexion there must be any prepared matter in the uterus which the semen masculinum, acting as a coagulating agent, should congeal, concoct, and fashion, or bring into a positive generative act, or, by drying its outer surface, include in membranes. Nothing certainly is to be seen within the uterus of the doe for a great number of days, namely, from the middle of September up to the 12th of November.
It appears moreover that all females do not shed seminal fluid into the uterus during intercourse; that there is no trace either of seminal fluid or menstrual blood in the uterus of the hind or doe, and many other viviparous animals. But as to what it is which is shed by women of warmer temperament no less than by men during intercourse, accompanied with failure of the powers and voluptuous sensations; whether it be necessary to fecundation, whether it come from the testes femininæ, and whether it be semen and prolific, is discussed by us elsewhere.
And whilst I speak of these matters, let gentle minds forgive me, if, recalling the irreparable injuries I have suffered, I here give vent to a sigh. This is the cause of my sorrow:—whilst in attendance on his majesty the king during our late troubles and more than civil wars, not only with the permission but by command of the Parliament, certain rapacious hands stripped not only my house of all its furniture, but what is subject of far greater regret with me, my enemies abstracted from my museum the fruits of many years of toil. Whence it has cometo pass that many observations, particularly on the generation of insects, have perished, with detriment, I venture to say, to the republic of letters.
Of what takes place in the uterus of the doe during the month of November.
Taught by the experience of many years I can state truly that it is from the 12th to the 14th of November that I first discover anything which belongs to the future offspring in the uterus of the hind.
I remember, indeed, that in the year of grace 1633, the signs of conception, or the commencements of the embryos, made their appearance somewhat earlier; because the weather was then cloudy and wet. In does, too, which have rutted six or seven days sooner than hinds, I have always discovered something of the future fœtus about the 8th or 9th of November. What this is and how it is begun I shall proceed to state.
A little before anything is perceptible, the substance of the uterus or its horns appears less than it was before the animals began to rut, the white caruncles are more flaccid, as I have said, and the protuberances of the internal coat subside somewhat, and are corrugated and look moist. For about the date above mentioned certain mucous filaments like spiders’ webs are observed drawn from the extremities, or superior angles of the cornua through the middle of either, and also through the body of the uterus. These filaments becoming conjoined present themselves as a membranous and gelatinous tunic or empty sac. Even as the plexus choroides is extended through the ventricles of the brain, is this oblong sac produced through the whole of either horn and the intervening cavity of the uterus, insinuating itself between the wrinkles of the flabby internal tunic, and sending delicate fibres among the aforementioned rounded protuberances, being nearly in the same manner as the pin mater dips between the convolutions of the brain.
Within a day or two this sac becomes filled with a clear,watery, sluggish albuminous matter, and now presents itself as a long-shaped pudding full of fluid. It adheres by its external glutinous matter to the containing walls of the uterus, but so that it is still easily separated from these; for if it be taken hold of cautiously in the strait of the uterus, where it is constricted in its course, it can be drawn entire out of either horn.
The conception arrived at this stage removed entire, presents itself with the figure of a wallet or double pudding; externally, it is covered with a purulent-looking matter; internally, it is smooth, and contains in its cavity a viscid fluid not unlike the thinner white of egg.
This is the conception of the hind and doe in its first stage. And since it has now the nature and state of an egg, and the definition given by Aristotle[338]of an egg is applicable to it, namely: “A body from one part of which an animal is produced, the remainder serving as nourishment to that which is engendered;” and farther, as it is the primordium of the future fœtus, it is therefore called the ovum, or egg of the animal, in conformity with that passage of the philosopher where he says:[339]“Those animals which engender internally, have a certain oviform body produced after the first conception. For a humour is included within a delicate membrane, such as that which you find under the shell in the egg of the hen; wherefore the blightings of conceptions that are apt to take place about this period are called fluxes.” This conception, therefore, as we have already said of the egg, is the true sperma or seed, comprising the virtue of both sexes in itself, and is analogous to the seed of the vegetable. So that Aristotle, describing the first conception of women, says,[340]that it is “covered with a membrane like an egg from which the shell has been removed;” such as Hippocrates describes as having been passed by the female pipe-player. And I have myself frequently seen such ova, of the size of pigeons’ eggs, and containing no fœtus, discharged by women about the second month after conception; when the ovum was of the size of a pheasant’s or hen’s egg, the embryo could be made out, the size of the little finger nail, floating within it. But the membrane surrounding the conception has not yet acquired any annexed placenta; neither isit connected with the uterus; there is only at its upper and blunter part a kind of delicate mossy or woolly covering which stands for the rudiments of the future placenta. The inner aspect is smooth and polished, and covered with numerous ramifications of the umbilical vessels. In the third month this ovum exceeds a goose’s egg in size, and includes a perfect embryo of the length of two fingers’ breadths. In the fourth month it is larger than an ostrich’s egg. All these things I have noted in the numerous careful dissections of aborted ova which I have made.
In the way above indicated do the hind and doe, affected by a kind of contagion, finally conceive and produce primordia, of the nature of eggs, or the seeds of plants, or the fruit of trees, although for a whole month and more they had exhibited nothing in the uterus, the conception being perfected about the 18th, at furthest, the 21st of November, and having its seat now in the right, now in the left horn, occasionally in both at once. The ovum at this time is full of a colliquate matter, transparent, crystalline, similar to that fluid which in the hen’s egg we have called the colliquament or eye, of far greater purity than that fluid in which the embryo by and by floats, and contained within a proper tunic of extreme tenuity, and orbicular in form. In the middle of the ovum, vascular ramifications and the punctum saliens—the first or rudimentary particle of the fœtus—and nothing else, are clearly to be perceived. This is the first genital part, which, once constituted, is not only already possessed by the vegetative, but also by the motive soul; and from this are all the other parts of the fœtus, each in its order, generated, fashioned, disposed, and endowed with life, almost in the same manner as we have described the chick to be produced from the colliquament of the egg.
Both of the humours mentioned are present in the conceptions of all viviparous animals, and are regarded by many as the excrements of the fœtus,—one the urine, the other the sweat, although neither of them has any unpleasant taste, and they are always and at all periods present in conceptions, even before a particle of the fœtus has been produced.
Of the membranes investing the two fluids, of which there are only two, the outer is called the chorion, the inner the amnion. The chorion includes the whole conception, and extends into either cornu; the amnion swimming in the midst of the liquid of the former, is found in one of the horns only, except in the cases where there is a twin conception, when there is an amnion present in each of them; just as in a twin-fraught egg there are two colliquaments. Where there are two fœtuses consequently, both are contained in one common conception, in one egg, as it were, with its two separate collections of crystalline fluid included. If you incise the external membrane at any point, the more turbid fluid which it contains immediately escapes from either horn of the uterus; but the crystalline liquid in the interior of the amnion does not escape at the same time unless the membrane have been simultaneously implicated.
The vein which is first discerned in the crystalline fluid within the amnion takes its rise from the punctum saliens, and assumes the nature and duty of an umbilical vessel; increasing by degrees it expands into various ramifications distributed through the colliquament, so that it seems certain that the nourishment is in the first instance derived from the colliquament alone in which the fœtus swims.
I have exhibited this point to his serene highness the king, still palpitating in the uterus laid open; it was extremely minute indeed, and without the advantage of the sun’s light falling upon it from the side, its tremulous motions were not to be perceived.
When the ovum with the colliquament entire was placed in a silver or pewter basin filled with tepid water, the punctum saliens became beautifully distinct to the spectators. In the course of the next ensuing days, a mucilage or jelly, like a tiny worm, and having the shape of a maggot, is found to be added; this is the rudiment of the future body. It is divided into two parts, one of which is the head, the other the trunk, precisely in the same way as we have already seen it in the generation of the chick in ovo. The spine, like a keel, is somewhat bent; the head is indifferently made up of three small vesicles or globules, and swimming in transparent water grows amain, and by degrees assumes its proper shape. There is only this to be observed, that the eye in embryos of oviparous animals is much larger and more conspicuous than that of viviparous animals.
After the 26th of November the fœtus is seen with its bodynearly perfect, in one case in the right in another in the left horn of the uterus; in twin cases in both horns.
At this time, too, the male embryo is readily distinguishable from the female by means of the organs of generation. These parts are also very conspicuous in the human embryo, and make their appearance at the same time as the trachea.
Males and females are met with indifferently in the right and left horn of the uterus. I have, however, more frequently found females in the right, males in the left horn; and I have made the same observation in does that carried twins, as well as in the sheep. It is certain, therefore, that the right or left side has no appropriate virtue in conferring sex; neither is the uterus, nor yet the mother herself, the fashioner or framer of the fœtus, any more than the hen is of the pullet in the egg which she incubates. In the same way as the pullet is formed and fashioned in the egg by an internal and inherent agent, is the fœtal form produced from the uterine ovum of the hind and doe.
It is indeed matter of astonishment to find a fœtus formed and perfected within the amnion in so short a space of time after the first appearance of the blood and punctum saliens. On or about the 19th or 20th day of November this punctum first becomes visible; on the 21st the shapeless vermiculus or maggot that is to form the body of the future animal is perceived; and in the course of from six to seven days afterwards a fœtus so perfect in all its parts is seen, that a male can be distinguished from a female by the organs of generation, and the feet are formed, the hooves being cleft, the whole having a mucous consistency and a pale yellowish colour.
The substance of the uterus begins to be extenuated immediately after the appearance of the embryo; contrary to what takes place in the human female, whose uterus grows every day thicker and fleshier with the advancing growth of the fœtus. In the hind and doe, on the other hand, the more the embryo augments the more do the cornua of the uterus assimilate themselves to the intestines; that horn in particular in which the fœtus is contained looks like a bag or pouch, and exceeds the opposite one in dimensions.
The ovum or conception, thus far advanced, and with its included fœtus perfectly distinct, has still contracted no adhesions to its mother’s sides: the whole can most readily be withdrawn from the uterus, as I have ascertained with an ovum which contained a fœtus nearly the length of the thumb. It is manifest, therefore, that the fœtus up to this period has been nourished by the albumen alone that is contained within the conception; in the same way as we have ascertained the process to go on within the hen’s egg. The mouths of the umbilical veins are lost and obliterated between the albumen and neighbouring humours of the conception and their containing membranes; but nowhere is there as yet any connexion with the uterus, although by these veins alone is nourishment supplied to the embryo. And as in the egg the ramifications of the veins are first sent to the colliquament, (in the same way as the roots of trees penetrate the ground,) and afterwards take their course to the external tunic called the chorion, whereon, for the sake of the nourishment, they are dispersed in an infinity of ramifications through the albuminous fluid contained within the outer membrane, so have I observed veins in the chorion of a human abortion; and Aristotle[341]also states “that membrane to be crowded with veins.”
If the fœtus be single its umbilical vessels are distributed to both horns, and a few twigs are also sent to the intervening body of the uterus; but if the conception be double, one in either horn, each sends its umbilical vessels to its own horn alone; the embryo in the right horn deriving nourishment from the right part of the conception, that in the left from the left portion of the same. In other respects the twin-conception here is precisely similar to the twin-conception of the egg.
Towards the end of November, then, all the parts are clearly and distinctly to be distinguished, and the fœtus is now of the size of a large bean or nutmeg; its occiput is prominent, as in the chick, but its eyes are smaller; the mouth extends from ear to ear, the cheeks and lips, as consisting of membranous parts, being perfected at a very late period. In the fœtuses of all animals, indeed, that of man inclusive, the oral aperture without lips or cheeks is seen stretching from ear to ear; and this is the reason, unless I much mistake, why so many are born with the upper lip divided as it is in the hare and camel, whencethe common name ofhare-lipfor the deformity. In the development of the human fœtus the upper lip only coalesces in the middle line at a very late period.
I have frequently put a fœtus the size of a large bean, swimming in its extremely pure nutritive fluid within the transparent amnion, into a silver basin filled with the clearest water, and have noted these particulars as most worthy of observation:—The brain of somewhat greater consistency than white of egg, like milk moderately coagulated, and of an irregular shape, and without any covering of skull, is contained within a general investing membrane. The cerebellum projects in a peak, as in the chick. The conical mass of the heart is of a white colour, and all the other viscera, the liver inclusive, are white and spermatic-looking. The trunk of the umbilical veins arises from the heart, and passing the convexity of the liver, perforates the trunk of the vena portæ, whence, advancing a little and subdividing into a great number of branches, it is distributed to the colliquament and tunica choroidea in innumerable fine filaments. The sides of the body ascend on either hand from the spine, so that the thorax presents itself in the guise of a boat or small vessel, up to the period at which the heart and lungs are included within its area, precisely and in all respects as we have seen it in the development of the chick. The heart, intestines, and other viscera, are very conspicuous, and present themselves as appendages of the body, until the thorax and abdomen being drawn around them, and the roof, as it were, put on the building, they are concealed within the compages of these cavities. At this time the sides both of the thorax and abdomen are white, gelatinous, and apparently identical in structure, save that a number of slender white lines are perceived in the walls of the thorax, as indications of the future ribs, whereby a distinction is here made between the bony and fleshy compages of the cavity.
I have also occasionally observed in conceptions of the sheep, which were sometimes twin, sometimes single, of corresponding age and about a finger’s breadth in length, that the form of the embryo resembled a small lizard of the size of a wasp or caterpillar; the spine being curved into a circle, and the head almost in contact with the tail. In the double conceptions both were of the same size, as if produced at once and simultaneously; each floated distinctly within the fluid of its own amnion; but although one lay in the right, the other in the left horn of the uterus, they were still both included in the same double sac or wallet, both belonged to the same ovum, and were surrounded by the same common external fluid. The mouth was large, but the eyes were mere points, so that they could scarcely be seen, very different, therefore, from what occurs among birds. The viscera in these embryos were also pendulous without the body,—not yet inclosed within the appropriate cavities. The outer membrane or chorion adhered in no way to the uterus, so that the entire conception was readily removed. Within the substance of the chorion innumerable branches of the umbilical vessels were conspicuous, but having no connexion whatsoever with the walls of the uterus; a circumstance to which allusion has already been made in the case of the deer; the distribution was in fact very much as we have found it on the external tunic of the hen’s egg. There were but two humours, and the same number of containing tunics, of which the chorion extending through both cornua, and full of a more turbid fluid, gave general configuration to the ovum or conception. The tunica amnios again is almost invisible, like the tunica arachnoides of the eye, and embraces the crystalline humour in which the embryo floats.
The fluid of the amnion was, in proportion, but a hundredth, or shall I say a thousandth, to that of the chorion; although the crystalline humour of the amnion was still in such quantity that no one could reasonably imagine it to be the sweat of the very small embryo that floated within it. It was, further, extremely limpid, and seemed to be without anything like bad taste or smell. It was, as we have already observed of the deer, in all respects like watery milk, and had none of the obnoxious qualities of an excrement. I add, that if this fluid were of an excrementitious nature it ought to increase in quantity with the growth of the fœtus. But I have found precisely the opposite of this to obtain in the conception of the ewe, so that shortly before she lambs there is scarce a drop of the fluid in question remaining. I am, therefore, rather inclined to regard it as aliment than as excrement.
The internal tunic of the uterus of the ewe is covered with caruncles innumerable, as the heavens are with stars. Theseare not unlike crabs’ eyes, and I have called them by this name; but they are smaller, like pendulous warts, glandular and white, sticking within the coats of the uterus, and somewhat excavated towards the conception; otherwise than in the deer, consequently, in which the caruncles corresponding to these rather project towards the embryo. These caruncles are gorged with blood, and their inner surface, where they regard the conception, is perceived to be beset with black sanguineous points. The umbilical vessels of the embryo were not yet connected with these caruncles, nor did the conception itself adhere to the uterus.
I find nothing of an allantois, of which something has been said as a tunic distinct from the chorion, in the conception of the ewe. At a later period, indeed, when the embryo is larger, when the ovum or conception has contracted adhesions with the uterus, and the umbilical vessels have penetrated the caruncles, the chorion extends further, and at its extremities on either side, and as it were in a couple of appendices, there is a certain fluid of a yellow colour, which you might call excrementitious, kept separate and distinct.
The human conception scarcely differs in any respect from an egg during the first months of pregnancy. I have observed a clear fluid, like the more liquid white of an egg, to be included within an extremely delicate membrane. At this time the placenta had not yet appeared, and the entire conception was of the size of a pigeon’s, or perhaps a pheasant’s egg. The embryo itself, of the length of the little finger nail, and having the form of a small frog, was conspicuous enough. The body was broad, the oral aperture widely cleft, the legs and arms like the stalks of flowers just risen above the ground, the occiput prominent, or rather forming a vesicle appended to the rest of the head, such as we have described the rudiments of the future cerebellum in the chick.
In another human conception of about the fiftieth day, the ovum was as large as a hen’s or a turkey’s egg. The embryo was as long as a large bean, the head of very large relative dimensions, and dominated by the cerebellum as by a kind of crest. The brain itself was of the consistence of curdled milk. Instead of a cranium there was a coriaceous membrane, in some places cartilaginous, and divided down the forehead tothe roots of the nostrils; the face looked like the muzzle of a dog. There were no external ears, nor any nose, yet could the rudiments of the trachea passing down to the lungs, and those of the penis, be detected. The two auricles of the heart presented themselves like eyes, of a black colour.
In the body of a woman who died of fever I found an hermaphrodite embryo nearly of the same size. The pudendum was like that of the rabbit, the labia standing for prepuce, the nymphæ for glans. In the upper part the root of the penis was also apparent, and on either side for the testicle there was the lax skin of the scrotum. The uterus was extremely diminutive, and in figure like that of the ewe or mole, with two horns. And as the prostate glands are situated near the penis of the boy, so were the testicles (ovaries) of visible dimensions, seen adjacent to these cornua. Externally considered, the sex seemed that of the male; internally, however, it was rather that of the female. The uterus of the mother was of great size, having the urinary bladder connected with it as an appendage. In the embryo, on the contrary, the bladder was large with the uterus of very small dimensions attached to it.
All the human ova that have been described above were, like those of the ewe, shaggy externally, and besmeared with a kind of gelatine, or glutinous matter. At this epoch, too, there was neither any placenta apparent, nor any visible connexion with the uterus; neither was there any implantation into the substance of the uterus of the umbilical vessels scattered over the surface of the conception itself.
As in the deer, so in the sheep, goat, and other bisulcated animals, do we find more than one fœtus in the same conception, just as in twin-fraught eggs we find two chicks surrounded by the same albumen. But in the dog, rabbit, hog, and other viviparous animals that produce a considerable number at a litter, the thing is otherwise. In these each fœtus has two humours, these being severally surrounded with their proper membranes.
In the bitch there are a number of knots or constrictions along the whole course of either cornu of the uterus, between each of which the appropriate humours and a single embryo are contained. In the hare and rabbit we observe a number of balls, like the eggs of serpents, so that the horns of the uteruslook like a pair of bracelets composed of so many amber beads strung upon a thread. The conception of the hare bears a strong resemblance to an acorn, the placenta embracing the embryo like a cup, and the humours inclosed in their membranes depending like the gland or nut.
Of the conception of the deer in the course of the month of December.
In the beginning of December the fœtus is seen larger, every way more perfect, and the length of the finger. The heart and other viscera which formerly hung externally are now concealed within the cavities of the body, so that they can no longer be seen without dissection.
The conception, or ovum, by the medium of the five caruncles which we have already spoken of as present in either cornu, is now in connexion with the uterus at an equal number of points; still the union is not so strong but that a very slight rather than a great effort suffices to break it. When the conception is detached, we perceive points or depressions on the surface of the chorion at the places where the adhesions to the uterus had existed, these spots being further covered with a certain viscid and wrinkled matter, as if this had been the bond of union between the mother and the ovum. Thus have we the nature and use of these caruncles made known to us: seen in the first instance as fungi or excrescences growing from the sides of the uterus, they are now recognized in connexion with the conception, as standing instead of the placenta or uterine cake in the human subject, and performing the same office. These caruncles are in fact but as so many nipples, whence the embryo by means of its umbilical vessels receives the nourishment that is supplied by the mother, as shall be clearly shown by what is to follow.
The size and capacity of the uterus, by which name we understand the cornua, or place occupied by the conception, is increased in proportion to the growth of the embryo; in suchwise, however, that the horn in which the fœtus is lodged is larger than the other.
The conception or ovum is single, whether one or several embryos are evolved from it; and it extends, as already said, into both of the horns, so that it presents itself with the shape of a double pudding, or rather of a single pudding having a constriction in its middle. Proceeding rounded and slender from the upper extremity of one of the horns, the conception gradually enlarges, and is produced into that common cavity which in the human female is called the uterus or matrix; (because, by conceiving and cherishing her offspring in this place the woman is made a mother;) the conception of the deer, passing through a kind of isthmus in the body of the uterus, is narrowed; but by and by, escaping into the other cornu, it there expands at first, but anon contracts again, and finally ends as it began in a tapering extremity. The whole conception, therefore, taken out entire, resembles a wallet filled with water on either side; and hence the chorion is also called allantois, because the conception in the lower animals, such as the deer, looks like an intestine inflated, or stuffed and tied in the middle.
In the embryo anatomized at this period every internal part is seen distinct and perfect; particularly the stomach, intestines, heart, kidneys, and lungs, which, divided into lobes, but having the proper form of the organs, look bloody. The colour of the lungs is deeper than it is in those fœtuses that have breathed, because the lungs, dilated by the act of respiration, assume a whiter tint. And by this indication is it known whether a mother has brought forth a living or dead child; in the former case the colour of the lungs is changed, and the change remains though the infant have died immediately afterwards.
In the female fœtus the testes—improperly so called—are seen situated near the kidneys at the extremities of the cornua uteri on either side; they are relatively of larger size than in the adult, and, like the caruncles of the uterus, look white.
In the stomach of the fœtus there is a watery fluid contained, not unlike that in which it swims, but somewhat more turbid or less transparent. It resembles the milk that begins to be secreted in the breasts of pregnant women about the fourth orfifth month of pregnancy, and may be pressed out of the nipples, or it is like the drink which we call white posset.
In the small intestines there is an abundance of chyle concocted from the same matter; in the colon greenish fæces and scybala begin to appear.
I do not find the urachus perforate; neither do I perceive any difference between the tunica allantoides or allantois, which is said to contain urine, and the chorion. Neither do I detect any urine in the secundines, but only in the bladder, where indeed it is present in large quantity. The bladder, of an oblong form, is situated between the umbilical arteries as they proceed from the bifurcation of the descending aorta.
The liver is rudely sketched and almost shapeless, as if it were a mere accidental part; it looks like a red coloured mass of extravasated blood. The brain, with some pretensions to regularity of outline, is contained within the dura mater. The eyes are concealed under the eyelids, which are as firmly glued together as we find them in puppies for some short time after birth, so that I found it scarcely possible to separate them and open the eyes. The breast-bones and ribs have a certain degree of firmness, and the colour of the muscles changes from white to blood red.
By the great number of dissections which I performed in the course of this month, I was every day confirmed in my opinion that the carunculæ of the uterus perform the office of the placenta; they are at this time found of a reddish colour, turgid, and of the size of walnuts. The conception, which had previously adhered to the caruncles by the medium of mucor or glutinous matter only, now sends the branches of its umbilical vessels into them, as plants send their roots into the ground, by which it is fastened and may be said to grow to the uterus.
About the end of December the fœtus is a span long, and I have seen it moving lustily and kicking; opening and shutting its mouth; the heart, inclosed in the pericardium, when exposed, was found pulsating strongly and visibly; its ventricles, however, were still uniform, of equal amplitude of cavity and thickness of parietes; and each ending in a separate apex, they form together a double-pointed cone. Occasionally I have seen the fluid contained in the auricles of the heart, which atthis time present themselves as ample sacs filled with blood, continuing to pulsate for some short time after the ventricles themselves had left off contracting.
The internal organs, all of which had lately become perfect, were now larger and more conspicuous. The skull was partly cartilaginous, partly osseous. The hooves were yellowish, flexible, and soft, resembling those of the adult animal softened in hot water. The uterine caruncles, of great magnitude and like immense fungi, extended over the whole cavity of the uterus, and plainly performed the office of placentæ, for numerous and ample branches of the umbilical vessels penetrated their substance there to imbibe nutritive matter for the growth of the embryo. As in the fœtus after birth, the chyle is now carried by the mesenteric veins to the porta of the liver.
Where there is a single fœtus the umbilical vessels are distributed to the whole of the carunculse, both those of the horn where the fœtus is lodged and those of the opposite horn; where there is a pair of embryos formed, the umbilical vessels of each only extend to the caruncles of the horn appropriated to it.
The smaller umbilical veins in tending towards the fœtus, form larger and larger trunks by coalescing, until at length two great canals are formed, which in conjunction pour their blood into the vena cava and vena portæ. But the umbilical arteries, which arise from the division of the descending aorta, form two trunks of small size, not remarkable save for their pulse: proceeding to the boundary of the conception, in other words, to the conjunction of the placenta or carunculæ with the ramifications of the umbilical veins, they first divide into numerous capillary twigs, and then are lost in others that are invisible.
As the extremities of the umbilical veins within the uterus terminate in the caruncles, so the uterine vessels on the outside, which are large and numerous, and bring the blood from the mother towards the uterus, by means of the vessels of the suspensory ligaments, terminate externally on the caruncles. It is to be noted, also, that the internal vessels are almost all veins; the external vessels, again, are in many instances branches of arteries. In the placenta of the woman, if it be carefully examined immediately after delivery, a much larger number of arteries than of veins, and these of larger size, will be founddispersed on every side in innumerable subdivisions to the very edge of the mass. In the same kind of spongy parenchyma of the spleen, the number of the arteries is also greater than that of the veins.
The exterior uterine vessels run to the uterus, as I have said, not to the ovaries (testiculi) situated in the suspensory ligament, as some suppose.
I have remarked an admirable instance of the skill of nature, in the bulge or convexity of the caruncles turned towards the conception: a quantity of white and mucilaginous matter is discovered in a number of cavities, cotyledons, or little cups; these are all as full of this matter as we ever see waxen cells full of honey; now this matter, in colour, consistency, and taste, is extremely like white of egg. On tearing the conception away from the caruncles, you will perceive numbers of suckers or capillary branches of the umbilical veins, looking like lengthened filaments, extracted at the same time from every one of the cotyledons and pits, and from amidst their mucilaginous contents; very much as we see the delicate filaments of the roots of herbs following the stem when it is pulled out of the ground.
It is clearly ascertained from this that the extremities of the umbilical vessels are not conjoined by any anastomosis with the extremities of the uterine vessels; that they do not imbibe any blood from them, but that they end and are obliterated in that mucilaginous matter, and from it take up their nourishment, nearly in the same way as at an earlier period they had sought for aliment from the albuminous humour contained within the membranes of the conception. In the same manner, consequently, as the chick in ovo is nourished by the white of the egg through its umbilical vessels, is the fœtus of the hind and doe nourished by a similar albuminous matter laid up in these cells, and not directly from the blood of the mother.