But upon this point we shall have more to say below, when we come to

speak of the manner in which the fœtuses of viviparous animals are

developed, and at the same time demonstrate that these all derive their

origin from eggs, and live by a twofold albuminous food in the womb. One

of these is thinner, and contained within the ovum or conception; the

other is obtained by the umbilical vessels from the placenta and uterine

cotyledons. The fluid of the ovum resembles a dilute albumen in colour

and consistence; it is a sluggish, pellucid liquid, in all respects

similar to that which we have called the colliquament of the egg, in

which the embryo swims, and on which it feeds by the mouth. The fluid

which the fœtus obtains from the uterine placenta by the aid of the

umbilical vessels is more dense and mucaginous, like the inspissated

albumen. Whence it clearly appears that the fœtus in utero is no more

nourished by its parent’s blood than is the suckling afterwards, or the

chick in ovo; but that it is nourished by an albuminous matter concocted

in the placenta, and not unlike white of egg.

Nor is the contemplation of the Divine Providence less useful than

delightful when we see nature, in her work of evolving the fœtus,

furnishing it with sustenance adapted to its varying ages and powers,

now more easy, by and by more difficult of digestion. For as the fœtus

acquires greater powers of digesting, so is it supplied with food that

is successively thicker and harder. And the same thing may be observed

in the milk of animals generally: when the young creature first sees the

light the milk is thinner and more easy of concoction; but in the course

of time, and with increased strength in the suckling, it becomes

thicker, and is more abundantly stored with caseous matter. Those flabby

and delicate women, therefore, who do not nurse their own children, but

give them up to the breast of another, consult their health

indifferently; for mercenary nurses being for the major part of more

robust and hardy frames, and their milk consequently thicker, more

caseous, and difficult of digestion, it frequently happens that milk of

this kind given to the infants of such parents, particularly during the

time of teething, is not well borne, but gives rise to crudities and

diarrhœas, to griping, vomiting, fever, epilepsy, and other formidable

diseases of the like nature.

What Fabricius says,[316] and strives to bolster up by certain

reasonings, of the chalazæ standing for the matter of the chick, we have

already thrown out in our history, and at the same time have made it

manifest that the substance of the chick and its first rudiments were

produced whilst the chalazæ were still entire and unchanged, and in a

totally different situation.

Neither is it true, as he states,[317] “that the chalazæ, rendered

fruitful by the semen of the cock, stand in the place of seed, and that

from them the chick is produced.” Nor are the chalazæ, as he will have

it,[318] “in colour, substance, and bodily properties so like seed, or

bear so strong a resemblance to the embryo in a boiled egg, that we may

rightly conceive all the parts designated spermatic to be thence

engendered.” I am rather of opinion that the fluid which we have called

colliquament, or the thinner portion of the albumen liquefied and

concocted, is to be regarded as of the nature of seed, and, if the

testimony of our eyes is to be credited, as a substitute for it.

The observation of this venerable old man is therefore unnecessary when

he says,[319] “As the whole animal body is made up of two substances

very different from one another, and even of opposite natures, viz. hot

and cold--among the hot parts being included all those that are full of

blood and of a red colour; among the cold all those that are exsanguine

and white--these two orders of parts doubtless require a different and

yet a like nourishment, if it be true that we are nourished by the same

things of which we are made. The spermatic, white, and cold parts,

therefore, require white and cold nourishment; the sanguineous, red, and

hot parts, again, demand nourishment that is red and hot. And so is the

cold white of the egg properly held to nourish the cold and white parts

of the chick, and the hot and sanguine yelk regarded as a substitute for

the hot and purple blood. In this way do all the animal parts obtain

nourishment suitable and convenient for them.” Now we by no means admit

that the two fluids or matters of the egg are there as appropriate means

of nourishment for different orders of parts. For we have already said

that the heart, lungs, kidneys, liver, spleen, muscles, bones,

ligaments, &c., &c., were all alike and indiscriminately white and

bloodless on their first formation.

Further, on the preceding view of Fabricius it would follow that the

heart, lungs, liver, spleen, &c., were not spermatic parts, did not

originate from the seed (which he, however, will by no means allow),

inasmuch as they too are by and by nourished by the blood and grow out

of it; for every part is both formed and nourished by the same means,

and nutrition is nothing more than the substitution of a like matter in

the room of that which is lost.

Nor would he find less difficulty in answering the question how it

happens that when the albumen in the egg is all consumed, the cold and

white parts, such as the bones, ligaments, brain, spinal marrow, &c.,

continue to be nourished and to grow by means of the vitellus? which to

these must be nourishment as inappropriate as albumen to the hot, red,

and sanguine parts.

Adopting the views commented on, indeed, we should be compelled to admit

that the hot and sanguineous parts were the last to be produced: the

flesh after the bones; the liver, spleen, and lungs after the ligaments

and intestinal canal; and further, that the cold parts of the chick must

come together and attain maturity, the white being all the while

consumed, and the hot parts be engendered subsequently, when the

vitellus fails and ceases from nourishing them; and then it would be

certain that all the parts could not take their rise in and be

constituted out of the same clear liquid. All such conclusions, however,

are refuted by simple ocular inspection.

I add another argument to those already supplied: the eggs of

cartilaginous fishes--skates, the dog-fish, &c.,--are of two

colours--their yelks are of a good deep colour; nevertheless all the

parts of these fishes are white, bloodless, and cold, not even excepting

the substance of their liver. On the contrary, I have seen a certain

breed of fowls of large size, their feathers black, their flesh well

supplied with blood, their liver red; yet were the yelks of the eggs of

these fowls--fruitful eggs--of the palest shade of yellow, not deeper

than the tint of ripe barley straw.

Fabricius, however, seems in these words[320] to retract all he has but

just said: “There is one thing to be particularly wondered at both in

the yelk and the white, viz. that neither of them being blood, they are

still so near to the nature of blood that they in fact differ but very

slightly from it--there is but little wanting to constitute either of

them blood; so that little labour and a very slight concoction suffice

to effect the change. The veins and arteries distributed to the

membranes of both the white and yelk are consequently seen replete with

blood at all times; the white and yelk nevertheless continuing possessed

of their own proper nature, though either, so soon as it is imbibed by

the vessels, is changed into blood, so closely do they approach in

constitution to this fluid.”

But if it be matter of certainty that blood exists no less in the

vessels distributed to the albumen than in those sent to the vitellus,

and that both of these fluids are so closely allied to blood in their

nature, and turn into blood so readily; who, I beseech you, will doubt

that the blood, and all the parts which are styled sanguineous, are

nourished and increased through the albumen as well as the vitellus?

Our author, however, soon contrives a subterfuge from this conclusion:

“Although all this be true,” he says,[321] “still must we conceive that

the matter which is imbibed by the veins from the yelk and white is only

blood in the same sense as the chyle in the mesenteric veins, in which

nothing but blood is ever seen; now chyle is but the shadow of blood,

and is first perfected in the liver; and in like manner the matter taken

up by the veins from the white and yellow is only the shadow of blood,”

&c. Be it so; but hiding under this shadow, he does not answer the

question, wherefore the blood and blood-like parts should not, for the

reasons cited, be equally well nourished by the albumen as by the

vitellus?

Had our author, in like manner, asserted that the hotter parts are

rather nourished by that blood which is derived from the vitellus than

by that attracted from the albumen, and the colder parts, on the other

hand, by that which is derived from the albumen, I should not myself

have been much disposed to gainsay him.

There is one consideration in the whole question, however, which is

sorely against him; it is this--how is the blood formed in the egg? by

what agent is either white or yelk turned into blood whilst the liver is

not yet in existence? For in the egg, at all events, he could not say

that the blood was transfused from the mother. He says, indeed, “This

blood is produced and concocted in the veins rather than in the liver;

but it becomes bone, cartilage, flesh, &c. in the parts themselves,

where it undergoes exact concoction and assimilation.” In this he adds

nothing; he neither tells us how or by what means perfect blood is

concocted and elaborated in the minute veins both of the albumen and

vitellus, the liver, as I have said, not having yet come into

existence,--not a particle of any part of the body, in fact, having yet

been produced by which either concoction or elaboration might be

effected. And then, forgetful of what he has previously said, viz. that

the hot and hæmatous parts are nourished by the vitellus and the cold

and anæmic parts by the albumen, he is plainly in contradiction with

himself when he admits that the same blood is turned into bone,

cartilage, flesh, and all other parts.

More than this, Fabricius has slipped the greatest difficulty of all,

the source of not a little doubt and debate to the medical mind, viz.

how the liver should be the source and artificer of the blood, seeing

that this fluid not only exists in the egg before any viscus is formed,

but that all medical writers teach that the parenchymata of the viscera

are but effusions of blood? Is the work the author of its workman? If

the parenchyma of the liver come from the blood, how can it be the cause

of the blood?

What follows is of the same likelihood: “There is another reason

wherefore the albumen should be separated from the yelk, namely, that

the fœtus may swim in it, and be thus supported, lest tending downwards

by its own weight, it should incline to one particular part, and

dragging, should break the vessels, in preventing which the viscidity

and purity of the albumen contribute effectually. For did the fœtus grow

amid the yelk, it might readily sink to the bottom, and so cause

laceration of that body.” Sufficiently jejune! For what, I entreat, can

the _purity_ of the albumen contribute to the support of the embryo? Or

how should the thinner albumen sustain it better than the thicker and

more earthy yelk? Or where the danger, I ask, of its sinking down, when

we see that the egg in incubation is always laid on its side, and there

is nothing to fear either for the ascent or the descent of the embryo?

It is indubitable, indeed, that not only does the embryo of the chick

float in the egg, but that the embryo of every animal during its

formation floats in the uterus; this however takes place amidst the

fluid which we have called colliquament, and neither in the albumen nor

vitellus, and we have elsewhere given the reason wherefore this is so.

“Aristotle informs us,” says Fabricius, “that the vitellus rises to the

blunt end of the egg when the chick is conceived; and this because the

animal is incorporated from the chalaza, which adheres to the vitellus;

whence the vitellus which was in the middle is drawn towards the upper

wider part of the egg, that the chick may be produced where the natural

cavity exists, which is so indispensable to its well-being.” The

chalaza, however, is certainly connected still more intimately with the

albumen than with the yelk.

My mode of interpreting the ascent in question is this: the spot or

cicatricula conspicuous on the membrana vitelli, expands under the

influence of the spirituous colliquament engendered within it, and

requiring a larger space, it tends towards the blunt end of the egg. The

liquefied portion of the vitellus and albumen, diluted in like manner,

and concocted and made more spirituous, swims above the remaining crude

parts, just as the inferior particles of water in a vessel, when heated,

rise from the bottom to the top, a fact which every medical man must

have observed when he had chanced to put a measure of thick and turbid

urine into a bath of boiling water, in which case the upper part first

becomes clear and transparent. Another example will make this matter

still more plain. There is an instrument familiar to almost everybody,

made rather for amusement than any useful purpose, nearly full of water,

on the surface of which float a number of hollow glass beads which by

their lightness and swimming together support a variety of figures,

Cupids with bows and quivers, chariots of the sun, centaurs armed, and

the like, which would else all sink to the bottom. So also does the eye

of the egg, as I have called it, or first colliquament, dilated by the

heat of the incubating fowl and genital virtue inherent in the egg,

expand, and thereby rendered lighter, rise to the top, when the

vitellus, with which it is connected follows. It is because the

cicatricula, formerly situated on the side of the vitellus, now tends to

rise directly upwards that the thicker albumen is made to give place,

and the chalazæ are carried to the sides of the egg.

EXERCISE THE SIXTY-FIRST.

_Of the uses of the other parts of the egg._

The shell is hard and thick that it may serve as a defence against

external injury to the fluids and the chick it includes. It is brittle,

nevertheless, particularly towards the blunt end, and as the time of the

chick’s exclusion draws near, doubtless that the birth may suffer no

delay. The shell is porous also; for when an egg, particularly a very

recent one, is dressed before the fire, it sweats through its pores. Now

these pores are useful for ventilation; they permit the heat of the

incubating hen to penetrate more readily, and the chick to have supplies

of fresh air; for that it both breathes and chirps in the egg before its

exclusion is most certain.

The membranes serve to include the fluids, and therefore are they

present in the same number as these, and therefore is the colliquament

also invested, as soon as it is produced, with a tunica propria, which

Aristotle[322] refers to in these words: “A membrane covered with

ramifications of blood-vessels already surrounds the clear liquid,” &c.

But the exit of the chick being at hand, and the albumen and

colliquament being entirely consumed, all the membranes, except that

which surrounds the vitellus, are dried up and disappear; the membrana

vitelli, on the contrary, along with the yelk, is retracted into the

peritoneum of the chick and included in the abdomen. Of the membranes

two are common to the whole egg, which they surround immediately under

the shell; the rest belong, one to the albumen, one to the yelk, one to

the colliquament; but all still conduce to the preservation and

separation of the parts they surround. The outer of the two common

membranes which adheres to the shell is the firmer, that it may take no

injury from the shell; the inner one again is smooth and soft, that it

may not hurt the fluids; in the same way, therefore, as the meninges of

the brain protect it from the roughness of the superincumbent skull. The

internal membranes, as I have said, include and keep separate their

peculiar fluids, whence they are extremely thin, pellucid, and easily

torn.

Fabricius ascribes great eminence and dignity to the chalazæ, regarding

them as the parts whence the chick is formed; he, however, leaves the

spot or cicatricula connected with the membrana vitelli without any

office whatsoever, looking on it merely as the remains of the peduncle

whence the vitellus was detached from the vitellarium in the superior

uterus of the hen. In his view the vitellus formerly obtained its

nourishment either by this peduncle or the vessels passing through it;

but when detached, and no longer nourished by the hen, a simple trace of

the former connexion and important function alone remains.

I however am of opinion that the uses of the chalazæ are no other than

those I have assigned them, namely, that they serve as poles to the

microcosm of the egg, and are the association of all the membranes

convoluted and twisted together, by which not only are the several

fluids kept in their places, but also in their distinct relative

positions. But I have absolute assurance that the spot or cicatricula in

question is of the very highest importance; it is the part in which the

calor insitus nestles; where the first spark of the vital principle is

kindled; for the sake of which, in a word, the whole of the rest of the

fluids and all the membranes of the egg are contrived. But this has been

already insisted on above.

Formerly, indeed, I did think with Fabricius that this cicatricula was

the remains or trace of the detached peduncle; but I afterwards learned

by more accurate observation that this was not the case; that the

peduncle, by which the vitellus hangs, was infixed in no such limited

space as we find it in apples and plums, and in such a way as would have

given rise to a scar on its separation. This peduncle, in short, expands

like a tube from the ovary on towards the vitellus, the horizon of which

it embraces in a bipartite semicircle, not otherwise than the tunica

conjunctiva embraces the eye; and this in suchwise that the superior

part of the vitellus, or the hemisphere which regards the ovary, is

almost free from any contact or cohesion with the peduncle, in the

superior part of the cup or hollow of which nevertheless, but somewhat

to the side, the spot or cicatricula in question is placed. The

peduncles becoming detached from the vitelli can therefore in no way be

said to leave any trace of their attachments behind them. Of the great

importance of this spot in generation I have already spoken in the

historical portion of my work.

But I have still, always following my old teacher Fabricius as my guide

on the way, to treat of the uses of the cavity in the blunt end of the

egg.

Fabricius enumerates various conveniences arising from this cavity,

according to its dimensions. I shall be brief on the subject: it

contains air, and is therefore useful in the ventilation of the egg,

assisting the perspiration, refrigeration, and respiration, and finally

the chirping of the chick. Whence this cavity, small at first, is larger

by and by, and at last becomes of great size, as the several offices

mentioned come into play.

Thus far have we spoken of the generation of the egg and chick, and of

the uses of the several parts of the egg; and to the type exhibited we

have referred the mode of generation of oviparous animals in general. We

have still to speak of the generation of viviparous animals, in doing

which we shall as before refer all to a single familiarly known species.

EXERCISE THE SIXTY-SECOND.

_An egg is the common origin of all animals._

“Animals,” says Aristotle,[323] “have this in common with vegetables,

that some of them arise from seed, others arise spontaneously; for as

plants either proceed from the seed of other plants, or spring up

spontaneously, having met with some primary condition fit for their

evolution, some of them deriving their nourishment from the ground,

others arising from and living on other plants; so are some animals

engendered from cognate forms, and others arise spontaneously, no kind

of cognate seed having preceded their birth; and whilst some of them

are generated from the earth, or putrefying vegetable matter, like so

many insects, others are produced in animals themselves and from the

excrementitious matters of their parts.” Now the whole of these, whether

they arise spontaneously, or from others, or in others, or from the

parts or excrements of these, have this in common, that they are

engendered from some principle adequate to this effect, and from an

efficient cause inherent in the same principle. In this way, therefore,

the primordium from which and by which they arise is inherent in every

animal. Let us entitle this the primordium vegetale or vegetative

incipience, understanding by this a certain corporeal something having

life in potentia; or a certain something existing _per se_, which is

capable of changing into a vegetative form under the agency of an

internal principle. Such primordia are the eggs of animals and the seeds

of plants; such also are the conceptions of viviparous animals, and the

worm, as Aristotle calls it, whence insects proceed: the primordia of

different living things consequently differ from one another; and

according to their diversities are the modes of generation of animals,

which nevertheless all agree in this one respect, that they proceed from

the vegetal primordium as from matter endowed with the virtue of an

efficient cause, though they differ in respect of the primordium which

either bursts forth, as it were, spontaneously and by chance, or shows

itself as fruit or seed from something else preceding it. Whence some

animals are spoken of as spontaneously produced, others as engendered by

parents. And these last are again distinguished by their mode of birth,

for some are oviparous, others viviparous, to which Aristotle[324] adds

a vermiparous class. But if we take the thing as simple sense proclaims

it, there are only two kinds of birth, inasmuch as all animals engender

others either in actu--virtually, or in potentia--potentially. Animals

which bring forth in fact and virtually are called viviparous, those

that bring forth potentially are oviparous. For every primordium that

lives potentially, we, with Fabricius, think ought to be called an egg,

and we make no distinction between the worm of Aristotle and an egg,

both because to the eye there is no difference, and because the

identity is in conformity with reason. For the vegetal primordium which

lives potentially is also an animal potentially. Nor can the distinction

which Aristotle[325] made between the egg and the worm be admitted: for

he defines an egg to be that “from part of which an animal is produced;

whilst that,” he says elsewhere,[326] “which is totally changed, and

which does not produce an animal from a part only, is a worm.” These

bodies, however, agree in this, that they are both inanimate births, and

only animals potentially; both consequently are eggs.

And then Aristotle himself, whilst he speaks of worms in one place,

designates them by the name of eggs in another.[327] Treating of the

locust, he says,[328] “its eggs become spoiled in autumn when the season

is wet;” and again, speaking of the grasshopper, he has these words,

“when the little worm has grown in the earth it becomes a matrix of

grasshoppers (tettigometra);” and immediately afterwards, “the females

are sweeter after coitus, for then they are full of white eggs.”

In this very place, indeed, where he distinguishes between an egg and a

worm, he adds:[329] “but the whole of this tribe of worms, when they

have come to their full size, are changed in some sort into eggs; for

their shell or covering hardens, and they become motionless for a

season, a circumstance that is plainly to be seen in the vermiculi of

bees and wasps, and also in caterpillars.” Every one indeed may observe

that the primordia of spiders, silkworms, and the like, are not less to

be accounted eggs than those of the crustacea and mollusca, and almost

all fishes, which are not actually animals, but are potentially

possessed of the faculty of producing them. Since, then, those creatures

that produce actually are called viviparous, and those that produce

potentially either pass without any general distinguishing title or are

called oviparous and particularly as such productions are vegetal

primordia, analogous to the seeds of plants, which true eggs must needs

be held to be, the conclusion is, that all animals are either viviparous

or oviparous.

But as there are many species of oviparous animals, so must there also

be several species of eggs; for every primordium is not alike fit to

receive or assume every variety of animal form indifferently. Though we

admit, therefore, that eggs in a general sense do not differ, yet when

we find that one is perfect, another imperfect, it is obvious that they

differ essentially from one another. Perfect eggs are such as are

completed in the uterus, where they obtain their due dimensions before

being extruded; of this kind are the eggs of birds. Imperfect eggs,

again, are such as are prematurely excluded before they are of the full

size, but increase after they are laid; of this description are the eggs

of fishes, crustacea and mollusca; the primordia of insects, which

Aristotle entitles worms, are farther to be referred to this class, as

well as the primordia of those animals that arise spontaneously.

Moreover, although perfect eggs are of two colours, in other words, are

composed of albumen and vitellus, some are still only of one hue, and

consist of albumen alone. In like manner, of imperfect eggs, some from

which a perfect animal proceeds are properly so called; such are the

eggs of fishes; others are improperly so styled, they engendering an

imperfect animal, namely, a worm, grub, or caterpillar, a kind of mean

between a perfect and an imperfect egg, which, in respect of the egg or

the primordium itself, is an animal endowed with sense and motion, and

nourishing itself; but in respect of a fly, moth or butterfly, whose

primordium it is potentially, it is as a creeping egg, and to be reputed

as adequate to its own growth; of this description is the caterpillar,

which having at length completed its growth is changed into a chrysalis

or perfect egg, and ceasing from motion, it is like an egg, an animal

potentially.

In the same way, although there are some eggs from the whole of which a

perfect animal is produced by metamorphosis, without being nourished by

any remains of the substance of the egg, but forthwith finds food for

itself abroad, there are others from one part of which the embryo is

produced, and from the remainder of which it is nourished:--although, I

repeat, there are such differences among eggs, still, if we be permitted

to conclude on the grounds of sense and analogy, there is no good reason

wherefore those that Aristotle calls worms should not be spoken of as

eggs; inasmuch as all vegetal principles are not indeed animals

actually, but are so potentially, are true animal seeds, analogous to

the seeds of vegetables, as we have already demonstrated in the

particular instance of the hen’s egg. All animals are, therefore, either

viviparous or oviparous, inasmuch as they all either produce a living

animal in fact, or an egg, rudiment, or primordium, which is an animal

potentially.

The generation of all oviparous animals may therefore be referred to

that of the hen’s egg as a type, or at all events deduced from thence

without difficulty, the same things and incidents that have been

enumerated in connexion with the common fowl being also encountered in

all other oviparous animals whatsoever. The various particulars in which

they differ one from another, or in which they agree, either generally,

or specifically, or analogically, will be subsequently treated of when

we come to speak of the generation of insects and the animals that arise

equivocally. For as every generation is a kind of way leading to the

attainment of an animal form, as one race of animal is more or less like

or unlike another, their constituent parts either agreeing or

disagreeing, so does it happen in respect of their mode of generation.

For perfect nature, always harmonious with herself in her works, has

instituted similar parts for similar ends and actions: to arrive at the

same results, to attain the same forms, she has followed the same path,

and has established one and the same method in the business of

generation universally.

Wherefore as we still find the same parts in the perfect or two-coloured

egg of every bird, so do we also observe the same order and method

pursued in the generation and development of their embryos as we have

seen in the egg of the common fowl. And so also are the same things to

be noted in the eggs of serpents and of reptiles, or oviparous

quadrupeds, such as tortoises, frogs, and lizards, from all the perfect

two-coloured eggs of which embryos are produced and perfected in the

same manner. Nor is the case very different in regard to fishes. But of

the manner in which spiders and the crustacea, such as shrimps and

crabs, and the mollusca, such as the cuttlefish and calamary, arise from

their eggs; of the conditions also upon which worms and grubs first

proceed from the eggs of insects, which afterwards change into

chrysalides or aurelias, as if they reverted anew to the state of eggs,

from which at length emerge flies or butterflies--of the several

respects in which these differ in their mode of generation from an egg,

from what we have found in the hen’s egg, will be matter for remark in

the proper place.

Although all eggs consisting of yelk and white are not produced and

fecundated in the same manner, but some are made prolific through the

intercourse of male and female, and others in some other way (as of

fishes); and although there is some difference even in the mode in which

eggs grow, some attaining maturity within the body of the parent, others

continuing to be nourished and to grow when extruded, there is still no

reason why an embryo should not be developed in the same precise manner

in every egg--always understood as perfect--as it is in the egg of the

hen. Wherefore the history which has been given of the evolution of the

chick from the hen’s egg may be regarded as applicable to the generation

of all other oviparous animals whatsoever, as well as to the inferences

or conclusions which may be deduced from thence.

EXERCISE THE SIXTY-THIRD.

_Of the generation of viviparous animals._

Thus far have we treated mainly of the generation of oviparous animals;

we have still to speak particularly of the other species of generation,

the viviparous, to wit, in which many things identical with those we

have noticed in oviparous generation will come to be observed. These we

have reduced into order, and here at length present for consideration.

Even the parts that appear paradoxical and in contradiction with the

current views of generation will, I believe, be found entirely in

conformity with truth.

Among viviparous animals, man, the most perfect of all creatures,

occupies the foremost place; after him come our ordinary domestic

animals, of which some are soliped, such as the horse and ass; others

bisulcate, as the ox, goat, sheep, deer, and hog; others digitate, such

as the dog, cat, rabbit, mouse, and others of the same description; from

the modes of whose generation a judgment may be formed of that of all

other viviparous animals. Wherefore I shall propose a single genus, by

way of general example or type, as we did in the case of the oviparous

class; this made familiar to us, will serve as a light or standard, by

means of which all the others may be judged of by analogy.

The reasons that led me to select the hen’s egg as the measure of eggs

in general have been already given: eggs are of little price, and are

everywhere to be obtained, conditions that permit repeated study, and

enable us cheaply and readily to test the truth of statements made by

others.

We have not the same facilities in studying the generation of viviparous

animals: we have rarely, if ever, an opportunity of dissecting the human

uterus; and then to enter on the subject experimentally in the horse,

ox, sheep, goat, and other cattle, would be attended with immense labour

and no small expense; dogs, cats, rabbits, and the like, however, will

supply those with subjects who are desirous of putting to the test of

experiment the matters that are to be delivered by us in this place.

Fabricius of Aquapendente, as if every conception of a viviparous animal

were in a certain sense an egg, begins his treatise with the egg as the

universal example of generation; and among other reasons for his

conclusions assigns this in particular:[330] “Because the study of the

egg has the most extensive application, the greater number of animals

being engendered from eggs.” Now we, at the very outset of our

observations, asserted that ALL animals were in some sort produced from

eggs. For even on the same grounds, and in the same manner and order in

which a chick is engendered and developed from an egg, is the embryo of

viviparous animals engendered from a pre-existing conception. Generation

in both is one and identical in kind: the origin of either is from an

egg, or at least from something that by analogy is held to be so. An egg

is, as already said, a conception exposed beyond the body of the parent,

whence the embryo is produced; a conception is an egg remaining within

the body of the parent until the fœtus has acquired the requisite

perfection; in everything else they agree; they are both alike

primordially vegetables, potentially they are animals. Wherefore, the

same theorems and conclusions, though they may appear paradoxical, which

we drew from the history of the egg, turn out to be equally true with

regard to the generation of animals generally. For it is an admitted

fact that all embryos, even those of man, are procreated from some

conception or primordium. Let us, therefore, say that that which is

called primordium among things arising spontaneously, and seed among

plants, is an egg among oviparous animals, i. e. a certain corporeal

substance, from which, through the motions and efficacy of an internal

principle, a plant or an animal of one description or another is

produced; but the prime conception in viviparous animals is of the same

precise nature, a fact which we have found approved both by sense and

reason.

What we have already affirmed of the egg, viz. that it was the sperma or

seed of animals and analogous to the seeds of plants, we now affirm of

the conception, which is indeed the seed of an animal, and therefore

also properly called ovum or egg. Because “a true seed,” according to

Aristotle,[331] “is that which derives its origin from the intercourse

of male and female, and possesses the virtues of both; such as is the

seed of all vegetables, and of some animals, in which the sexes are not

distinct, and is, as that which is first mingled from male and female, a

kind of promiscuous conception or animal; for it has those things

already that are recognised of both;” i. e. matter adapted to nourish

the fœtus, and a plastic or formative and effective virtue. And so in

like manner is a conception the fruit of the intercourse of male and

female, and the seed of the future embryo; it therefore does not differ

from an egg.

“But that which proceeds from the generant is the cause which first

obtains the principle of generation, (i. e. it is the efficient cause,)

and ought to be called the geniture,”[332] not the seed, as is commonly

done both by the vulgar and philosophers at the present time; because it

has not that which is required of both the concurring agents, neither is

it analogous to the seeds of plants. But whatever possesses this, and

corresponds to the seeds of vegetables, that too is rightly entitled egg

and conception.

Further, the definition of an egg, as given by Aristotle,[333] is

perfectly applicable to a conception:--“An egg,” he says, “is that the

principal part of which goes to constitute an animal, the remainder to

nourish the animal so constituted.” Now the same thing is common to a

conception, as shall be made to appear visibly from the dissection of

viviparous animals.

Moreover, as the chick is excluded from the egg under the influence of

warmth derived from the incubating hen or obtained in any other way,

even so is the fœtus produced from the conception in the uterus under

the genial warmth of the mother’s body. In few words, I say, that what

oviparous animals supply by their breast and incubation, viviparous

animals afford by their uterus and internal embrace. For the rest, in

all that respects the development, the embryo is produced from the

conception in the same manner and order as the chick from the egg, with

this single difference, that whatever is required for the formation and

growth of the chick is present in the egg, whilst the conception, after

the formation of the embryo, derives from the uterus of the mother

whatever more is requisite to its increase, by which it continues to

grow in common with the fœtus. The egg, on the contrary, becomes more

and more empty as the chick increases; the nutriment that was laid up in

it is diminished; nor does the chick receive aught in the shape of new

aliment from the mother; whilst the fœtus of viviparous animals has a

continued supply, and when born, moreover, continues to live upon its

mother’s milk. The eggs of fishes, however, increase through nourishment

obtained from without; and insects and crustaceous and molluscous

animals have eggs that enlarge after their extrusion. Yet are not these

called eggs the less on this account, nor, indeed, are they therefore

any the less eggs. In like manner the conception is appropriately

designated by the name of ovum or egg, although it requires and procures

from without the variety of aliment that is needful to its growth.

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 them down 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.”

EXERCISE THE SIXTY-FOURTH.

_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.

EXERCISE THE SIXTY-FIFTH.

_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 therefore the 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 even without 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 be left 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 treating of

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 chyle and 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 larger kinds 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 the _place_ of the conception in them

rather of the nature of an uterine horn than the uterine body. For the

_place_ here 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.

EXERCISE THE SIXTY-SIXTH.

_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 their stand 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.

EXERCISE THE SIXTY-SEVENTH.

_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 ask myself 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.

EXERCISE THE SIXTY-EIGHTH.

_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 was only 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 be pregnant 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 come to

pass that many observations, particularly on the generation of insects,

have perished, with detriment, I venture to say, to the republic of

letters.

EXERCISE THE SIXTY-NINTH.

_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 is it 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 body nearly

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, whence the

common name of _hare-lip_ for 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. These are 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

to the 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 uterus look 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.

EXERCISE THE SEVENTIETH.

_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 or fifth 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 at

this 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 found dispersed 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.

These carunculæ might therefore with propriety be called the uterine

liver, or the uterine mammæ, seeing that they are organs adapted for the

preparation and concoction of that albuminous aliment, and fitting it

for absorption by the veins. In those viviparous animals consequently

that have neither caruncles nor placentæ, as the horse and the hog, the

fœtus is nourished up to the moment of its birth by fluids contained

within the conception or ovum; nor has the ovum in these animals at any

time a connexion with the uterus.

From all of what precedes it is manifest that in both the classes of

viviparous animals alluded to, those, namely, that are provided with

carunculæ or cotyledons, and those that want them, and perhaps in

viviparous animals generally, the fœtus in utero is not nourished

otherwise than the chick in ovo; the nutritive matter, the albumen,

being of the same identical kind in all. As in the egg the terminations

of the umbilical vessels are in the white and yelk, so in the hind and

doe, and other animals furnished with uterine cotyledons like them, the

final distributions of the umbilical vessels are sent to the humours

that are included within the conception or ovum, and to the albumen that

is stored in the cotyledons, or cup-like cavities of the carunculæ,

where they open and end. And this is further obvious from the fact of

the extremities of the umbilical vessels, when they are drawn out of the

afore-mentioned mucor, looking completely white; a certain proof that

they absorb this mucilage liquefied only, and not blood. The same

arrangement may very readily be observed to obtain in the egg.

The human placenta is rendered uneven on its convex surface, and where

it adheres to the uterus, by a number of tuberous projections, and it

seems indeed to adhere to the uterus by means of these; it is not

consequently attached at every point, but at those places only where the

vessels pierce it in search of nourishment, and at those where, in

consequence of this arrangement, an appearance as if of vessels broken

short off is perceived. But whether the extremities of these vessels

suck up blood from the uterus, or rather a certain concocted matter of

the nature of albumen, as I have described the thing in the hind and

doe, I have not yet ascertained.

Finally, that the truth just announced may be still more fully

confirmed, it is found that by compressing the uterine caruncles between

the fingers, about a spoonful of the nutritive fluid in question may be

obtained from each of them, as from a nipple, unmixed with blood, which

is not obtained even with forcible pressure. Moreover, the caruncle thus

milked and emptied, like a compressed sponge, contracts and becomes

flaccid, and is seen to be pierced with a great number of holes. From

everything, therefore, it appears that these caruncles are uterine

mammæ, or fountains and receptacles of nutritive albumen.

The month of December at an end, the caruncles adhere less firmly to the

uterus than before, and a small matter suffices to detach them. The

larger the fœtus grows, indeed, the nearer it is to its term, the more

readily are the caruncles detached from the uterus, so that, like ripe

fruit from the tree, they slip at length from the uterus of themselves,

and as if they had formed an original element in the conception.

Separated from the uterus you may perceive in the prints which they

leave points pouring out blood; these are the arteries that entered

them. But if you now detach the conception from the caruncles, no blood

is effused; none escapes, save from the ends of the vessels proceeding

from the conception, although it does seem more consonant with reason to

suppose that blood should be shed from the caruncles than from the

conception when they are forcibly separated. For, as the caruncles or

cotyledons have an abundance of uterine branches distributed to them,

and they are generally believed to receive blood for the nourishment of

the fœtus, we should expect that they would appear replete with blood.

Nevertheless, as I have said, they yield no blood either under milking

or compression, and the reason of this is that they contain albumen

rather than blood, and rather store up than prepare this matter. It

seems manifest, therefore, that the fœtus in utero is not nourished by

its mother’s blood, but by this albuminous fluid duly elaborated. It may

even be perhaps that the adult animal is not nourished immediately by

the blood, but rather by something mixed with the blood, which serves as

the ultimate aliment; as may perhaps be more particularly shown in our

PHYSIOLOGY and particular treatise on the Blood.