MONSTER. 



Uie kin and boon ; in the other it ii more deeply seated, the cavities 

 of the body at the point of union communicating in the two individuals, 

 or being in fact converted into one ; thus, the chest* being united, the 

 sternum may be altogether deficient ; and the thoracic cavities thrown 

 into communication, in which case the viscera frequently present 

 some anomaliei in form and arrangement. Sometimes there are two 

 hearts, which are perfectly distinct, and inclosed in separate pericardia ; 

 sometimes the heart*, though both well formed, are contained in one 

 common pericardium, in which they may be either distinct from each 

 other, or superficially joined at some point In other cage* two hearts 

 are found, but both in a very imperfect state ; lastly, there may be 

 only one heart presenting several vices of conformation, as three or 

 four ventricles, or one of the two ordinary ventricles unusually large, 

 and partly divided by a septum. In other canes of this description 

 the heart hat been found single and well formed, but the large 

 vnsseli have been all double, so that two aortas sprung from the left 

 ventricle, &c. 



In >ome instances of double monstrosity the component individuals 

 are distinct and separate at their lower halves, but more or less 

 intimately united at the upper part of their bodies, so that they appear 

 to have a double body and single head. In others, on the contrary, 

 there are two distinct bends, and the upper part of the body is double, 

 while the pelvis and inferior extremities ore nearly or quite single. 

 In some came belonging to the former of these divisions the separation 

 of the bodies is only complete inferiorly, all the parts above the 

 umbilicus manifesting a tendency to coalesce : in others the separation 

 is perfect as high as the neck. In all these instances however the 

 head and upper part of the body, although apparently single, almost 

 invariably present on dissection some supernumerary parts, which 

 clearly indicate their double origin. Those compound monsters which 

 are furnished with two heads and a single body offer numerous varie- 

 ties; the head may be double, but not distinctly divided, there being 

 two faces, more or less perfectly formed, placed side by side, and 

 separated by a longitudinal division ; each face is generally provided 

 with a pair of eyes, but sometimes there are only three, one being 

 placed in the median line and formed by the union of two together, 

 as in cases of Cyclopia. The two heads may be completely double, 

 but the body and extremities single. Lastly, the heads and upper 

 halves of the bodies may be separate, there being four upper extre- 

 mities, while the monster is only single by the pelvis and lower 

 extremities. A human monster of the last kind, which lived to be 

 nine months old, excited great interest in Paris in 1829; it was a 

 double female, and denominated Rita-Christina, It was born in 

 Sardinia, and was brought to Paris to be publicly exhibited. It was 

 carefully examined after death, and a detailed account of its structure 

 baa been given by M. Serrcs, in his ' Kecherches d'Anatomie Trans- 

 cendante,' 4c. The two vertebral columns were found quite distinct 

 in their whole length, and a rudimentary pelvis separated them 

 inferiorly : another fuHy developed pelvis was found in its natural 

 position, which supported two well formed abdominal limbs. There 

 existed a single bladder, uterus, and rectum, which were common to 

 the two subject*, but behind these organs were found rudimentary 

 traces of others. There were two distinct hearts, nnd all the other 

 thoracic and most of the abdominal viscera were double. 



A singular and unique case is recorded by Sir K. Home (' Philos. 

 Trans.,' voL Ixxx. p. 296, and vol Ixxxix. p. 28 ; also in ' Lectures on 

 Comparative Anatomy,' t iii. p. 334), of a foetus with an accessory 

 head, which was implanted by its summit on to the crown of the natural 

 bead. The body of this child was well formed in every respect, having 

 no supernumerary parts, and the principal head was quite natural in 

 appearance, except in the parietal region, where its integuments were 

 continued into those of the accessory head. The latter was placed in 

 an entirely inverted position, the neck, which terminated in a round 

 tumour, being directed upwards and a little backwards. This 

 monstrous child, which was born in Bengal in 1783, lived to be four 

 years old, and then only died from the bite of a serpent. In this case, 

 which must be included with those of double monstrosity, we must 

 mippoee that the body and limbs belonging to the accessory head had 

 become completely atrophied, but it is exceedingly curious how this 

 remaining part continued to live solely by means of vascular and 

 nervous communication with the principal individual, and without 

 any separate umbilical cord or special organs of nutrition. 



The last variety of montrosity which we shall mention is that by 

 inclusion. In these cases fragment* of one foetus have been found 

 contained in the interior of another. A case of this kind is recorded 

 by M. Dupuytron (' Bull, de la Faculte" de MiSdecine,' voL L), who 

 found a cyst in the transverse mesocoloii of a boy 18 years of age, 

 containing an organised mass, which, when carefully examined, pre- 

 sented trace* of the brain, spinal marrow, nerves, muscles, and most 

 of the bone* of a foetus, but no vestiges of the organs of digestion, 

 respiration or circulation. Similar substance* have been found in 

 various situations in other subjects, and there is no doubt of their 

 natnro; though the mode in which the germ of one foetus ha* 

 become included in the body of another is at present entirely 

 unknown. 



Compound monsters, formed by the union of more than two distinct 

 individual* are exceedingly rare, and very few authentic ca*es of such 

 anomaly are on record. 



MOXSTElt. sn 



None of the different theories which have been proposed in explana- 

 tion of the mode of origin of single monster* throw any light on the 

 cause* of compound montrosity. It is very difficult to decide whether 

 the germs have been originally double, or whether two or more have 

 become united during the progress of development The latter is the 

 most general opinion; and the most probable idea respecting their 

 mode of union is, that two ova become adherent whenever they are 

 contained within the same membrane*, and opposed to each other by 

 corresponding aspect* of the body. 



Of the predisposing and exciting causes of monstrosity little is 

 known; for while the influences determining the phenomena of normal 

 development are hidden from us, those presiding over irregular forma- 

 tion must necessarily be involved in darkness. In the article Fomra 

 it is stated that the organs of the embryo are generally considered to 

 be successively developed, and not evolved from originally pre-existing 

 elements : the notion therefore that the germ of the future embryo is 

 over originally monstrous previous to impregnation must be abandoned, 

 and the causes giving rise to the various forms of congenital malforma- 

 tion mult be sought for in some accidental influences disturbing or 

 arresting the process of development in the embryo. Direct evidence 

 ha* been afforded by experiment that the natural stages of formation 

 may be BO altered in the embryo of the chick during incubation by 

 external injury. Geoffrey St Hilaire injured several egg* in which 

 the process of incubation had commenced, and had been going on 

 naturally for several days. He shook some of them violently, he 

 perforated the shell of others in different places with a sharp instru- 

 ment, or kept them in a vertical position, upon either the large or 

 .small end, during tho whole time of hatching ; again, in some he 

 covered part of the shell with wax, or a varnish impervious to the 

 air. The constant effect of these injuries was the production of a 

 very considerable number of anomalies, either simple or complicated, 

 among which may be mentioned Cyclopia and other malformations of 

 the face and head, eventration, and spinal fissure. In no instance was 

 any case of double montrosity met with, which might, a priori, have 

 been supposed ; a double monster being composed of two distinct 

 embryos, the germs of which must have previously existed in the same 

 egg. (' Memoires du Museum,' torn. xiii. p. 289 ; also ' Journal Com- 

 plement des Sci. Mod.,' torn, xxxiv.) 



The younger St Hilaire repeated these experiments in a diti 

 manner, altering the structure of eggs previous to the commencement 

 of incubation, and not during the course of this process, as had been 

 done by hi* father. His experiments were attended with quite a 

 different result : the more violent disturbing influences destroyed the 

 vitality of the embryo altogether ; others, less active, produced general 

 retardation or arrest of the process of development of the whole body; 

 but in no instance was malformation of any one' region or part effected. 

 (' Hist des Auom.' torn, iii., p. 03.) These experiments confirm the 

 opinion that anomalies involving a single individual must principally 

 I if iviVrred to the influence of some disturbing causes occurring during 

 the process of development In some instances the birth of a monster 

 ha* undoubtedly followed an accident received by the mother during 

 the early months of gestation, such as a fall, a violent blow on the 

 abdomen, or some long-continued mental impression or anxiety. The 

 influence of such causes is however much weaker than has been sup- 

 posed ; for how many examples occur every day of women producing 

 well-formed children who have been suffering under violent moral 

 emotions, or who have received serious accidents during pregnancy. It 

 is unnecessary to bring forward any arguments to refute the ancient 

 superstitious notions of the vast influence which the imagination of the 

 mother was supposed to exert over the formation of the foetus. It is 

 no longer supposed, except by the ignorant, that any object which has 

 been seen or longed for by the parent can be depicted on the body of 

 the child ; and in most case* where tha child has been supposed to 

 have been deformed through the influence of any such cause, if the 

 date of the impression received by the mother be carefully ascertained, 

 it will be found that the organ supposed to be altered or marked by 

 such impression must have been nearly or fully developed at tho time 

 that it was received, and therefore could be in no way affected. 



Another very generally admitted cause for some malformations is 

 the occurrence of disease in the foatus itself, and there is no doubt but 

 that some cases of anencephalia and other malformations of the brain 

 and spinal chord must be referred to dropsical disease occurring in 

 the interior of the skull and spiue of the embryo ; but in tho majority 

 of cases this explanation is inadmissible, and supported by no proofs. * 

 Many other hypotheses have been proposed to account for the pro- 

 duction of monster* a* adhesions between the foetus and its investing 

 membranes ; modifications in the quantity and quality of the nutri- 

 ment received by the embryo; pressure made on the foatus by tumours 

 attached to the parietes of the uterus, Ac. It is unnecessary to enter 

 into the consideration of these causes ; for, after all, we can only arrive 

 at the conclusion that the development of the embryo in anomalous 

 cases has been diverted from it* natural course, or arrested by some 

 accidental cause, which, whether taking its origin in the foetus itself, 

 or acting secondarily on the embryo, is involved in obscurity. 



Though the occurrence of accidental causes acting during the 

 process of development will account for most of the phenomena of 

 monstrosity, yet it will not account for all. It has'been observed that 

 some malformations are hereditary are transmitted from fathers to 



