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It is difficult to deny the fœtus all intellectual and moral manifestation. This must doubtless be obscurely rudimental, but still we may conceive that some may exist, if we admit, that the brain is in a state for the perception of impressions, and that tact is practicable, whilst instinct is in full activity.

We find, moreover, that the power of motion, voluntary as well as involuntary, exists certainly after the fifth month, and probably much earlier, could it be appreciated. During the latter months of utero-gestation, the motion of the fœtus appears to be almost incessant, and can be distinctly felt, by placing the hand upon the abdomen. At times, indeed, it is manifest to the sight. The cause of these movements is by no means clear. It is probable, however, that they are instituted for the purpose of inducing a change in positions which may have become irksome, and for assuming others; for we have already remarked, that the foetus readily appreciates any sudden succussion, given to it through the mother; hence that it possesses tact; and, as we can readily understand, may experience fatigue from the maintenance of an inconvenient posture. This impression is conveyed to the brain, which sends out volition to the appropriate muscles, and the position is changed. All this proves, that the cerebral functions are exerted, but for a few definite objects only.

The function of expression is of course almost, if not entirely, null in the fœtus. There are cases upon record, however, where children are said to have cried in utero, so as to be heard distinctly, not only by the mother, but by those around her. Indeed, the objection, that an infant may respire before it is born, and yet not come into the world alive,—in which case there will be buoyancy and dilatation of the lungs,—has been seriously brought forward against the docimasia pulmonum or lung-proof of infanticide. We would not be considered as believing these cases to be mere fabrications, or that the phenomenon is impossible,—except, indeed, whilst the membranes are in a state of integrity. When they have given way, and the child's mouth presents towards the os uteri, breathing may be practicable, and may have occurred; but very positive and unexceptionable testimony is required to establish such an astounding event.

II. Functions of Nutrition.—These functions are not as numerous in the fœtus as they are in the adult. Their object is, however, the same; the formation of the various parts of the organized machine, and their constant decomposition and renovation.

During the first few days of foetal existence, whilst the ovum is within the ovarium or Fallopian tube, and for a short period after its passage into the womb, the new being probably derives its nutriment from the albuminous matters with which it is in contact in the ovum, in the same manner as the egg of the oviparous animal obtains the nutriment necessary for its full development during incubation, from the matters surrounding it. But when it has attained the interior of the uterus, it is supposed that the ovum ab

sorbs nutriment from the mother. Chaussier conceives, that the ovule, on leaving the Fallopian tube, plunges into the midst of the sero-albuminous substance, which is copiously secreted in the uterus for the formation of the decidua, and that it nourishes itself by absorbing a quantity of this by its external surface, like the vegetable, and the lowest tribes of animals. The decidua, however, appears to be intended for a specific purpose, and is formed even prior to the passage of the ovule into the uterus. This, with the fact of the ovule containing nutritive matter within it for the nutrition of the embryo, is sufficient to render the view of Chaussier improbable.

The liquor amnii, in which the child is situated during the whole period of utero-gestation, has been regarded by many physiologists as concerned in fœtal nutrition; but great dissidence has prevailed with regard to the mode in which it is introduced. The arguments, usually adduced in favour of this function of the liquor amnii, are, the nutritive nature of the fluid, young animals having been fed upon it for several weeks,—the fact of its being more abundant and richer in animal matter in proportion as the fœtus is young, -its continual contact with the foetus, whose surfaces, internal as well as external, have been supposed to possess a greater absorbent power in proportion to the nonage of the foetus, and the fact of fœtuses, devoid of umbilical cord, having undergone their development without the aid of a placenta.

The circumstance of the first developments being made in the ovarium from the absorption of the nutritive matter surrounding the embryo, is so far in favour of the foetus obtaining its nutriment from the substances in contact with it, rather than by means of the maternal blood; and the view is favoured by the phenomena that occur in eggs hatched out of the body, where of course there can be no farther communication with the mother.

The most forcible arguments, however, are those deduced from the fact, which seems unquestionable, that neither the placenta nor umbilical cord is indispensably necessary to foetal development. Adelon disposes of this in the most summary manner; affirming that "there is no authentic instance of a fœtus devoid of umbilical cord and placenta, attaining full uterine growth." The case is not, however, got rid of so easily, and it environs this intricate subject with additional difficulties. The kangaroo, opossum, and wombat, breed their young without either placenta or umbilical cord. The embryos are inclosed in one or more membranes, which are not attached to the coats of the uterus, and are supplied with nourishment, and apparently with air, from a gelatinous matter, by which they are surrounded. Good has cited a case from Hoffmann of a fœtus born in full health and vigour, with the funis sphacelated and divided into two parts; and another, from Van der Wiel, of a living child, exhibited without any umbilicus, as a public curiosity. One of the most singular cases, however, that has ever occurred,

was observed by Dr. Good himself in 1791. The labour was natural; the child, scarcely less than the ordinary size, was born alive; cried feebly once or twice after birth, and died in about ten minutes. The organization, both internal and external, was imperfect in many parts. There was no sexual character whatever, neither penis nor pudendum; nor any interior organ of generation. There was no anus or rectum, no funis, no umbilicus. The minutest investigation could not discover the least trace of any. With the use of a little force, a small, shrivelled placenta, or rather the rudiment of a placenta, followed soon after the birth of the child, without a funis or umbilical vessels of any kind, or any other appendage by which it appeared to have been attached to the child. In a quarter of an hour afterwards, a second living child was protruded into the vagina and delivered with ease, being a perfect boy, attached to its placenta by a proper funis. The body of the first child was dissected in the presence of Dr. Drake of Hadleigh, and of Mr. Anderson of Sunbury, to both of whom Dr. Good appeals for the correctness of his statement. In the stomach a liquid was found resembling the liquor amnii.

How could nutrition have been effected, then, in this case? Certainly not by blood sent from the mother to the child, for no apparatus for its conveyance was discoverable; and are we not driven to the necessity of supposing that the food must have been obtained from the fluid within the ovum? This case,—when taken with the arguments already adduced; along with the facts, that the embryo is found at an earlier period in the uterus than the placenta, which as we have seen cannot be detected till some weeks after conception; and that extra-uterine fœtuses have frequently no placenta, but obtain their nutriment from the surrounding parts,—seems to constrain us to admit, that the liquor amnii may have more agency in the nutrition of the new being than is generally granted. Professor Monro, amongst other reasons, all of which are of a negative character,—for his disbelief in this function of the liquor amnii, asserts, that if the office of the placenta be not that of affording food to the embryo, it becomes those, who maintain the contrary doctrine to determine what other office can be allotted to it, and that till this is done, it is more consistent with reason to doubt the few and unsatisfactory cases, at that time brought forward, than to perplex ourselves with facts directly contradictory of each other. The case, given by Dr. Good since Professor Monro's remarks were published, is so unanswerable and so unquestionable, that it affords a positive fact, of full or nearly full fœtal development, independently of placenta and umbilical cord; and the fact must remain, although our ignorance of the functions of the placenta, be "dark as Erebus."

Amongst those physiologists, who admit the liquor amnii to be a fluid destined for factal nutrition, a difference prevails, regarding the mode in which it is received into the system. BUFFON, OSIAN

DER and others consider, that it is absorbed through the skin. In the foetal state, the cuticle is extremely thin; and, until within a month or two of the full period, can be scarcely said to exist. There is consequently not that impediment to cutaneous absorption, which we have seen, exists in the adult. The strong argument, however, which they offer in favour of such absorption is the fact, that the foetus has been found developed, although devoid of both mouth and umbilical cord; and Professor Monro, in opposing the function ascribed to the liquor amnii, refers to cases of monstrous formations, in which no mouth existed, nor any kind of passage leading to the stomach.

Others, as Boerhaave and Haller are of opinion that the fluid enters the mouth and is sent on into the stomach and intestines; and in support of this view, they affirm, that the liquor amnii has been found in these viscera;—that it has been shown to exist in the stomach and pharynx. Heister on opening a gravid cow, which had perished from cold, found the liquor amnii frozen, and a continuous mass of ice extending to the stomach of the foetus.

The physiologists, who believe that the liquor amnii is received into the stomach, differ as to what happens to it in that organ. Some suppose, that it is simply absorbed, without undergoing digestion; others, that it must be first subjected to that process. According to the former opinion, it is simply necessary, that the fluid should come into contact with the mucous membrane of the alimentary passages; and they affirm, that if digestion occur at all, it can only be during the latter months.

Others, however, conceive, that the waters are swallowed or sucked in, and that they undergo true digestion. In evidence of this, they adduce the fact of meconium existing at an early period in the intestinal canal, which they consider as evidence that the digestive function is in action; and in farther proof of this they affirm, that on opening the abdomen of a new-born infant, the chyliferous vessels were found filled with chyle; which could not, they say, have been formed from any other substance than the liquor amnii; and lastly, that fine silky down has been found in the meconium, similar to that which exists on the skin of the fœtus, and which is conceived to have entered the mouth along with the liquor amnii.

These reasons are forcible, but they do not explain the development, in the cases above alluded to, in which there was no mouth; and of course, they cannot apply to acephalous fœtuses. Moreover, it has been properly remarked, that the presence of meconium in the intestinal canal merely proves that digestion has taken place, and the same may be said of the chyle in the chyliferous vessels: neither one nor the other is a positive evidence of the digestion of the liquor amnii: both might have proceeded from the digestion of the stomachal secretions. It has also been affirmed, that the meconium exists in the intestines of the acephalous fœtus, and in those in which the mouth is imperforate. Lastly, with re

gard to the down discovered in the meconium, it has been suggested as possible that it may be formed by the mucous membrane of the intestine, which so strongly resembles the skin in structure and functions.

Others have supposed that the liquor amnii is received by the respiratory passages, from the circumstance, that, in certain cases, the fluid has been found in the trachea and bronchi; some presuming, that it readily and spontaneously enters at the nostrils and passes to the trachea and bronchi; others that it is forced in by the pressure of the uterus; and others again, that it is introduced by the respiratory movements of the fœtus.

Views have differed in this case, also, regarding the action exerted upon it after introduction;—some, presuming that it is absorbed immediately; others, that it is inservient to a kind of respiration; and that, during fœtal existence, we are aquatic animals,—consuming the oxygen or atmospheric air which Scheele and others have stated to exist in the fluid.

It is scarcely necessary to seriously oppose these gratuitous speculations. The whole arrangement of the vascular system of the fœtus, so different from that which is subsequently established, and the great diversity in the lungs, prior and subsequent to respiration, would be sufficient to refute the idea, had it even been shown, that the liquor amnii always contains one or other of these gases, which is by no means the fact. The case of the acephalous foetus is also an obstacle to this view as strong as to that of the digestion of the liquor amnii.

As if to confirm the remark of Cicero—"nihil tam absurdum, quod non dictum sit ab aliquo philosophorum,"—it has been advanced by two individuals of no mean pretensions in science, that the liquor amnii may be absorbed by the genital organs or by the

mammæ.

Lobstein supports the former view, Oken the latter. Lobstein asserts, that the fluid is laid hold of by the mammæ, is elaborated by them, and conveyed from thence into the thymus gland, the thoracic duct, and the vascular system of the fœtus!

Of these various opinions, the one that assigns the introduction of the fluid to the agency of the cutaneous absorbents appears to carry with it the greatest probability. It must be admitted, however, that the whole subject is environed in obscurity, and requires fresh, repeated, and accurate experiments and observations to enlighten us.

But it may now be asked, with Monro, what are the nutritive functions performed by the placenta? We have seen that vessels pass between the mother and the maternal side of the placenta, and that others pass between the fœtus and the fœtal side, but that the two sides are so distinct, that we are justified in regarding them as two placentæ, the one maternal, the other foetal,—simply united to each other.

VOL. II.

47

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