What follows is an excerpt from a British Review Article on M. Isidore Geoffroy St. Hilaire's General and particular History of Anomalies of
Organization in Man and Animals which appeared in The British And Foreign
Medical Review (Vol 8, No. 15) July, 1839.
Histoire générale et particulière des Anomalies de
l'Organisation chez l'Homme et les Animaux, outrage comprenant des Recherches
sur les Caractères, la Classification, etc. des Monstruosités. Par M. Isidore
Geoffroy Saint Hilaire, M.D., &c. &c.—Paris,
1832-36. Trois Tomes, avec Atlas. 8vo, pp. 746, 571, 618.
A general and particular History of Anomalies of
Organization in Man and Animals, comprising Researches into the Characters,
Classification, &c. of Monstrosities. By M. Isidore Geoffroy St. Hilaire,
M.dD, &c. &c—Paris,
1832-36. 3 Vols. 8vo, with an Atlas.
Although some years have elapsed since the greater portion
of the work before us was published, yet, as no sufficient account of it has
hitherto appeared in our language, we think it important that our readers
should no longer be deprived of the highly interesting and valuable information
it contains, and shall therefore now present them with an analysis of it. In
executing our task we shall confine ourselves almost exclusively to the
exposition of the author's views; introducing our own opinions but sparingly,
even when they are at variance with those maintained in the original treatise.
On some future occasion we may take up the whole subject fundamentally; our
present object being rather to supply facts than to criticise doctrines.
The object of M. St. Hilaire's work is to give a complete
history of the subject of monstrosities: under which name all the various
congenital irregularities of form and structure, occasionally met with in man
and animals, are generally included. The author has collected together a great
number of facts, relating to the different forms and degrees of anomaly, which
he has systematically arranged in classes, orders, &c.; and he has
afterwards endeavoured to establish the laws and general relations to which all
the individual facts may be referred. He has shown how these laws and these
relations are themselves only derived from the common laws of organization, and
how, among the numerous theories of the formation and growth of animals which
have been proposed in modern times, those which are not applicable to anomalous
cases are also inapplicable to normal facts in general, and ought to be
rejected; and many principles, on the contrary, but slightly established at
present by the study of natural facts, find in the phenomena of monstrosities
complete elucidation. M. Isidore St. Hilaire has also pointed out that this
subject embraces all the conditions of organization in the various classes of
organized beings, and that there is scarcely any general fact, auy anatomical
or physiological law, on which it does not throw light and either confirm or
disprove. Thus the necessary consequence of an exact and profound knowledge of
anomalies will be, that the study of normal and abnormal facts, intimately
associated together, will lend to each other a mutual and powerful support.
A vast collection of most valuable materials on this subject
may be found scattered through various publications on natural and medical
science; but before the younger St. Hilaire (who has largely profited by his
father's labours) undertook the task of collecting them, there existed no
modern work which professed to give a complete and separate account of the
various anomalies of organization, such as might serve as a textbook, and for
the purposes of reference, in which all the varieties of monstrosity which have
been met with should be recorded, as well as the opinions of different writers
on their nature and causes.
Our author thinks that the consideration of the various
kinds of monstrosity, with the laws and causes of their formation, should form
a distinct branch of science, and should be treated of separately from
pathological or general anatomy and physiology, embryology, or zoology; with
all of which they have a very close connexion, and together with some of which
they have mostly been described. To this particular subject which M. Isidore
St. Hilaire has thus isolated from the sciences by which it is surrounded, he
has proposed that the name of Teratology* should be given, which he considers
preferable to the old denomination of monstrosities, the term which was
previously given to all kinds of congenital malformation. Our author's views as
to the separate place which Teratology should hold in science are supported by
Meckel, who supposes that the various species of monstrous formation compose a
series rising by regular gradations, from the natural shape to the most
unnatural deformity: and that the intermediate steps are not constituted by
single or individual cases, but that every variety of monstrous formation is
accurately repeated in other individuals; so that, in fact, a separate and independent
kingdom of monsters might be established.
Monstrosities have attracted the attention of philosophers
as well as the vulgar in all ages. Among the ancients, Hippocrates, Aristotle,
Pliny, Galen, and even Empedocles and Democritus noticed their occurrence and
investigated their causes; and these early writers had almost as accurate
notions of the nature, and gave as faithful descriptions of monstrous
formations, as any of the authors on this subject before the commencement of
the eighteenth century. Indeed, the history of monsters, till very lately, was
composed of a collection of marvellous tales, inaccurate descriptions, and
absurd and superstitious prejudices. This long period of ignorance, with
respect to their true nature, may be called the fabulous period in the history
of the science, and cannot be said to have terminated before the time of
Ambrose Paré. A few authentic and interesting cases, it is true, had been
already recorded; but these were only rare exceptions, which attracted little attention,
except when some author tried to give a new and ridiculous explanation of them,
derived from the fanciful ideas which were then exclusively prevalent. In fact,
monsters were regarded by the writers of the seventeenth century as by those of
preceding ages, as prodigies and sports of nature, arising from supernatural or
unnatural causes.
After the fabulous, succeeded what St. Hilaire has called
the positive period in the history of anomalies; it comprises about the first
half of the eighteenth century. Evident progress now commenced, and facts were
correctly observed, though still often explained on false principles. The most
celebrated authors of this age on teratology were found among the members of
the French Academy.
Méry, Duverney, Winslow, Lémery, and Littre may be particularly mentioned. In
the works of these great men, we not only find numerous facts accurately
observed and described, but many judicious remarks and violent attacks against
ancient prejudices. In place of those explanations of the phenomena of
monstrosity, which were admitted by the superstition of the preceding period,
they endeavoured to substitute scientific and reasonable theories. The causes
of monstrosity particularly excited attention; and though many errors were
fallen into, for want of the support of a sufficient number of facts, yet it
was discovered that one of the greatest difficulties was involved in the
question, whether monsters were formed so originally, or whether the
monstrosity was accidentally acquired. A very long and able controversy was
carried on concerning this point between Lémery and Winslow, the former of whom
contended that monstrosities were formed or arose during the growth of the
embryo; and modern discoveries in embryology have shown that he was correct,
though his rival, who held that the germs were originally monstrous, was
considered to have triumphed at the time.
The labours of these celebrated academicians conducted the
science to its last epoch, which may be denominated the scientific, and which
extends from the middle of the eighteenth century to the present time. It may
be divided into many periods; and it will be seen that a vast difference exists
between the state of teratology at its commencement and end, owing to the rapid
progress which science has made. Haller may be said to have commenced this era,
though Morgagni had previously corrected several erroneous opinions respecting
the nature and causes of monstrous formations. Haller, in his treatise De monstris, collected all the facts relating
to this subject which were recorded by his contemporaries and predecessors,
submitted them to a judicious analysis, and deduced from them several
conclusions eminently calculated to promote the advancement of this study.
Haller, however, fell into some fundamental errors, the most important of which
was that respecting the mode of the development of the embryo. He supposed (and
his theory prevailed till very lately, and is now partly entertained by some
physiologists,) that the development of the organs of the foetus was
centrifugal, or that the heart, brain, spinal cord, &c. were formed before
the vessels and nerves which were gradually developed from them. This theory,
as we shall presently show, is contrary to those laws of formation by which the
greater number of anomalies are explained by our author and other
teratologists.
The rapid advances which have led to the present state of
this department of science are owing to the indefatigable researches of modern
anatomists. The study of general and comparative anatomy led the way to the
true method of investigation, viz. that of comparing adult man to the embryo,
and various animals to man, both in the adult and foetal states. This
comparison has given rise to two new methods of investigation, which are now
almost universally recognized in the science of anatomy. One discloses the true
laws of organic formations; the other embraces the general facts of the
structure of animal bodies, considered in all ages and all species. Both of
these methods reveal to us important knowledge concerning the composition of
organs: the one plan assists us in learning the mode of their formation; and
the other decomposes them by a learned analysis, and shows us the elements,
everywhere identical, disposed according to invariable rules. Embryology is
thus placed upon its true basis, and philosophical anatomy created. Among those
naturalists to whom we are indebted for these researches, we may particularly
enumerate Geoffroy St. Hilaire (the father of our author) and M. Serres in France,
and Frederic Meckel and Tiedemann in Germany.
The various species of monstrous formations have been
referred to three classes, viz.
1. Anomalies which arise from arrest of formation or
development, in which various parts are found either imperfectly formed or
altogether deficient.
2. Anomalies from excess of formation or development, in
which some organs exceed their natural limits either in size or number.
3. Anomalies which result neither from arrest nor excess of
formation and development, but in which the formative process seems to have
been simply perverted, thus producing various modifications in the direction
and situation of organs. In this class M. Isidore St. Hilaire includes the
entire group of compound monstrosities, which result from the junction or
fusion of two or more separate individuals. These have generally been referred
to one of the previous classes.
The explanation of these different varieties of
organization, or the laws of anomalies, must be derived from the general laws
or principles of organization, which the study of philosophical anatomy and
embryology have revealed; and, before proceeding to the consideration of the
different varieties of monsters, we shall briefly mention the most interesting
of these laws, and explain the manner in which they elucidate the different
classes of monstrosities.
1. The first and most important is the law of unity of
organic composition.
One great principle reigns over the whole of zoological
science, that there is a unity of plan in the animal kingdom. Philosophical
anatomy has shown us that the organs of animals are composed of materials which
are always essentially the same, and which are combined according to definite
rules; and that curious and unexpected analogies often exist between beings
placed at the opposite extremities of the scale. If we admit the existence of a
distinct and peculiar plan of organization for each species, or even in
different families, we only obtain partial views, and the science will be
reduced to the sterile observation of facts, without reciprocal connexion,
rational analogies, or possible consequences. If, on the contrary, we elevate
our ideas to the conception of a unity of plan pervading the whole animal
kingdom, we shall only see in the multitude of beings which compose the animal
series, the innumerable parts of one immense whole, the infinite varieties of
one and the same type.
If we apply to the solution of the difficulties which this
subject presents, the theory of inequalities of formation and development, we
shall find it equally applicable to zoology as to teratology; and the
fundamental truth will be apparent, that one or more metamorphoses, to a
greater or less extent, sometimes consisting merely in a simple change in the
mode of evolution of an organ, will explain all those varieties of form and
structure which at the first aspect seem to arise from essential differences in
the formative process.
The series of species in the animal kingdom seems to be
parallel with the series or stages of formation or development in any
individual being, or, in fact, with the series of ages in that being; and the
facts of one are reciprocally connected with and explain those of the other.
The connexion between teratology and zoology is now seen. The theory of
inequality of formation and development relates both to the series of ages in
the embryo and the series of zoological species, as well as to the series of
monstrosities: it shows the parallel relation between the first and second as
well as between the first and third; and by the same laws the series of
zoological species and monstrous cases are necessarily analogous and parallel
to each other. Thus, in an abstract point of view, all the differences between
beings either normal or abnormal may be embraced in the same considerations and
referred to the same formulae: as, for instance,—the inferior beings are, as it
were, the permanent embryos of animals higher in the scale; and, reciprocally,
the superior beings, before they arrived at the definite forms which
characterize them, have transitorily offered those of the lower animals. This
must not be taken, however, quite literally; for the resemblance or analogy is
only seen between individual organs, not entire beings.
By this law of unity of type in the formation of animals
(which has been so fully exposed in the works of the elder St. Hilaire, Meckel,
and Serres,) may be explained the resemblances which have so often been
observed between the anomalous states of one species and the natural form of
another. Every animal in whom there has been arrest of development should
realize in some of its organs the conditions met with among the inferior
classes. Excess of development, on the contrary, should cause a resemblance
between the animal which is the subject of it and some of the beings higher in
the scale. Many examples of monstrosity have been brought forward in support of
this theory, and we may briefly state a few of them. The most numerous cases
are those in which the higher animals by arrest of development present the
characters which are natural to some inferior species. Thus man, when affected
with monstrosity, often has a marked resemblance in some characters with
different mammalia, as by the persistence of the tail,[i]
and by many anomalies in form either of the limbs, body, or head. Thus, by the
existence of a cloaca, labial fissure, duplicity of the uterus, smallness of
the brain, and absence or imperfect state of the convolutions, the malformed
human foetus presents characters which are all found existing naturally in
various species of rodentia, as the beaver, &c.
In some monsters there has been found bifurcation of the
glans penis or clitoris, and two vaginae, a disposition of parts existing
normally among marsupial animals. By imperforation of the vulva, and a separate
termination by distinct orifices, of the sexual and urinary organs, with
imperfect development of the eyes, the genus called aspalasomus and other monsters realize in man those organic
conditions, which in the normal state distinguish the mole and some other insectivora from all other mammalia. In
the genus of monsters, phocomeles,
the limbs are shortened, the hands and feet appearing to exist alone, and to be
inserted immediately on the trunk, as in the seals and the herbivorous cetacea.
In the rare monster, ectromeles, the
limbs are nearly or altogether deficient, as in the ordinary cetacea.[ii]
We may also often observe some of the conditions of animals
still lower in the scale, realized in human monsters; thus, there may be a
rudimentary state of the palatine arch, as in fishes; imperfect development of
the diaphragm, as in all oviparous animals; a communication between the
different cavities of the heart, as in reptiles; an absence of the brain and
spinal marrow; and a nervous system composed only of ganglions and nervous
filaments, as in the articulated animals.[iii]
Although the cases are much more rare in which the inferior
animals resemble the higher, from excess of development,[iv] yet
many instances of this kind have been met with. St. Hilaire has seen several
individuals among the carnivora in which the tail has disappeared, and the
spinal marrow has ascended in the vertebral canal, as it does in man and the
most highly-organized quadrumana. This anomaly also realizes the conditions met
with in some animals much lower in the series, as the anourous batrachians or
frogs, where there is a continuance or excess of the process of development in
the change from the tadpole to the perfect animal.
The possibility of referring the various species of monsters
to a common type is a necessary and easy deduction,—in fact, an indispensable
conclusion to be drawn from the theory of the unity of organic composition.
When we admit that the entire classes of the animal kingdom are established
upon one and the same plan, it becomes absurd to allow the existence of many
types in one family. From the natural relation which exists also between the
different degrees of monstrosity and the links in the animal chain results a
complete demonstration that monstrosity is not a blind disorder springing from
freaks of nature, but a particular class governed by constant and precise
rules, and capable of being systematically divided into definite tribes and
genera. The elder St. Hilaire, however, is disposed to consider each individual
monster as constituting in itself a distinct species; and he does not agree
with Meckel, that every variety of monstrous formation is accurately repeated
in other individuals.
2. The second law which we shall mention as being closely connected
with teratology is one of the fundamental principles of embryology: the basis,
in fact, upon which that science rests, viz., that no organs originally
preexist in the ovum, but are all formed at various periods of its growth.
Necessarily very minute and simple at the time of their early origin, the
different organs afterwards pass through a series of changes in the process of
development. These changes are far from being equal either in number or
importance, whether we compare together the same organ in different beings, or
different organs in the same being; so that, when arrived at their definitive
or permanent state, some have passed through a greater number of phases, and
have departed much more from their primitive conditions than others. Such is
the normal but not the invariable mode of development: an organ may stop
beneath its ordinary degree of perfection, or even be entirely abortive; it
may, on the contrary, exceed the natural term of its evolution, and thus will
arise the two groups of anomalies, opposite in their conditions of existence,
and also in their causes, to which so many of the species of monsters have been
referred, viz. arrest and excess of development.
The admission of the law of non-preexistence of organs in
the germ is fatal to the doctrine of original monstrosity existing before
fecundation: a doctrine conceived by Licetus and the older writers on this
subject, but which owed its celebrity to its adoption by Winslow and Haller. It
would now have been almost forgotten had not Meckel lately attempted to revive
it for the purpose of explaining the occurrence of certain monstrosities, the
origin of which cannot be understood in the present state of teratology, such
as the retroversion of the abdominal limbs and some other peculiarities of
organization, which are constantly associated with the junction of the legs in
the monsters named symeles. M. St.
Hilaire says that the only argument brought forward by Meckel in support of his
hypothesis is the impossibility of finding a satisfactory explanation of these
anomalies by the theory of accidental production of monstrosities: this is true
in the present state of science; but there is no reason why the obscurity of
this case should not one day be cleared up, like many other facts in teratology,
which were formerly thought inexplicable, and cited as certain proofs of the
original production of monstrosities, but which the ulterior progress of
science has discovered to be in support of the inverse theory.
According to the law which admits the formation and not the
evolution of organs, monsters from arrest of development may be considered in
some respects as permanent embryos: they show us at the termination of
intra-uterine life some of their organs in the simple state in which they were first
formed; as if nature had stopped in her course for the purpose of allowing us
the opportunity of observing her processes.
3. A third law is that of eccentric development. We have already remarked that Haller (and he
was followed by all the anatomists of the eighteenth century) considered that
the heart was formed before any other organ, and was itself the origin of all
the others; that it furnished the principal vascular trunks, which afterwards
subdivided into branches more and more minute. In the same manner the nervous
trunks were considered to derive their origin from the cerebro-spinal axis,
which was said to be first developed, and the larger nerves were afterwards
thought to ramify into the minute branches; in other words, all the vessels and
nerves, subdividing more and more, proceeded from the central parts of the
nervous and vascular systems towards the organs placed on the surface of the
body, to which they gave nourishment and life. This theory is denominated that
of centrifugal development, and has
still many supporters.
The inverse doctrine, that of eccentric or centripetal
development, was proposed by M. Serres, and is warmly supported by Geofiroy
St. Hilaire and his son: all the laws of teratology proposed by the father and
followed by his son in the present work are founded upon it, and by this theory
a great number of anomalies are explained. These anatomists say that the
vessels and nerves are formed before the heart and nervous centres; they first
originate in the superficial organs on the surface of the body, and are
gradually developed towards the centre; in support of this opinion it is said
that the heart, brain, and spinal cord have all of them been found wanting in
different monsters, while the vessels and nerves have never been seen wholly
deficient. The large trunks are also found more frequently irregular in their
course and distribution than the superficial branches of an artery or nerve,
and the contrary should be the case if the development was centrifugal, as it
has been observed that those organs which are latest formed are the least
constant.
According to the observations of M. Serres, the development
of the body commences on the surface of the two lateral halves, each central
and single organ being originally double, its right and left portions are at
first distinct and separate, and become afterwards united. If by any causes, as
arrest of development, the union of these two half-organs is prevented from
taking place, if this primitive state of formation becomes permanent, two
lateral organs are formed, which may be either entirely distinct or only
partially separated, according to the period of formation at which the arrest
of development took place. The median labial fissure (often confounded with the
lateral fissure or true hare-lip) has been thus explained, as well as fissure
of the palate, scrotum, urethra, and spinal fissure or spina bifida, &c. M.
Serres also states that the hollow organs situated in the median line are
composed originally of two halves; as well as the solid organs; and his
observations have been, to a certain extent, confirmed by Dr. Allen Thomson,
and others. Thus, according to our author, there are at one period two hearts
(this organ is placed in the first instance in the median line), two aortae,
two vaginae, uteri, bladders, &c. These organs are considered to pass
through three successive stages in the process of development: in the first
they are completely double, and the two portions quite separate; in the next
stage they approach and unite in the median line, the two inner walls being
applied against each other, and at the third period they become definitely
fused, the inner walls being removed, and all traces of separation lost. If by
arrest of development the second stage of formation becomes permanent, the
inner walls of the primitive organs which unite together and form naturally a
temporary septum are not removed, and the organ is intersected by a
longitudinal partition. Such an anomaly is sometimes met with in the human
subject, affecting the vagina and uterus, and realizing the natural conditions
of the sexual organs in some marsupial animals.
Another fact which is dependent upon the law of centripetal
development is the greater constancy of form in those organs which are of early
formation than in those later developed. When any cause comes into action at
any period of uterine life, by which the process of growth may be disturbed,
those organs which are already nearly or fully evolved will necessarily be
little or not at all altered; but a very marked change, on the contrary, may be
effected in those parts which are very imperfectly developed, or whose
formation has not even commenced. In the latter case complete atrophy may be
effected.
If we add, that in most of the systems of organs the
different parts are subordinate in their formation one to another, the second
being produced by the first, the third by the second, and so on, we shall see
that the suppression of any one of them, without having any influence on those
which preceded it, will necessarily cause the complete absence of all those
which ought to have followed it in the order of development. The results of
observation perfectly confirm these remarks; it has been found that the
umbilicus and small intestines are the parts most constant in monsters, and
also the organs first formed in the embryo; the spinal cord also is less often
wanting than the brain which it precedes, the aorta than the heart, &c. The
superficial and lateral parts of the body are also much more constant than the
central or medial organs, they often exist when the latter are wanting, and
they frequently present a regular conformation when the latter are seriously
modified or very incomplete. Many cases may be met with where the different
parts or organs have been reduced to their external covering or integument;
thus in the monsters named cyclocephali
and otocephali, in which the two eyes
or ears are in contact, or united in one, the nose is entirely rudimentary, the
bones, &c. being deficient, and only the skin remaining, which is sometimes
prolonged in the form of a snout or trunk: sometimes one of the abdominal limbs
has been found in this rudimentary state, and in some very imperfect monsters
the whole being seems to be reduced to the tegumentary covering, inclosing a
few unconnected parts, as bones, vessels, &c.
[i] In the
early stages of formation of the human fetus, there naturally exists a
prolongation of the coccyx, which is removed by the progress of development.
[ii] It is
proper to observe, however, that some of these cases were probably instances of
‘spontaneous amputation,’ and cannot,
therefore, be properly called monsters at all. Rev.
[iii] In the
last of these cases, no real analogy can bo said to exist.—Rev.
[iv] These anomalies appear to be more rare, perhaps, than
they really are, on account of the much greater number of monstrosities that
arc observed and examined in man than among animals.
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