FCETUS. 



317 



same time a very close and intimate mutual 

 dependence of the one on the other ; and, con- 

 trary to what we would at first expect, the 

 health of the mother is more apt to suffer from 

 morbid conditions of the fetus in utero than is 

 the latter to be injured in its developement by 

 the state of the mother's system. Thus we see 

 how great a disturbance is often caused in the 

 maternal system by a blighted ovum, or a dead 

 and putrid fetus ; while, on the other hand, 

 we frequently observe that women in states of 

 the most infirm health,* both mental and bo- 

 dily, nay even when sinking under the ravages 

 of some wasting disease, or depressed and worn 

 out by mental suffering, by want of food or ex- 

 cessive fatigue, give birth to full-grown and 

 well-thriven children. 



The affections to which the fetus is liable 

 vary not a little according to the period of its 

 existence at which we consider it ; during the 

 earlier periods, when the formative process is 

 in most active operation, and the developement 

 of the different organs is proceeding rapidly, 

 many important and remarkable organic altera- 

 tions take place ; some from arrest of develop- 

 ment caused by imperfection in or morbid 

 alteration of the structures of the ovum ; some 

 by destruction of parts already formed, by 

 atrophy or inflammation, or both conjoined ; 

 some by the effects of excessive secretion and 

 the consequent unnatural distension, &c. ; 

 while those affections, to which more strictly 

 belong the name of diseases, affect the more 

 matured fetus, whose organization approaches 

 more closely that of the new-born child. 



In order to give a full account of the morbid 

 and abnormal conditions of the fetus, we 

 should embrace also those of its appendages 

 or surrounding structures of the ovum ; these, 

 however, will be alluded to at present only so 

 far as is absolutely unavoidable, as they will 

 receive full consideration in the articles OVUM 

 and PLACENTA : and in like manner several 

 varieties of malformation will be with more 

 propriety described under the head of MON- 

 STROSITY, while others will be found under the 

 account of the different organs concerned. 



The germ, even before its vivification in the 

 ovary, may have a morbid taint communicated 

 to it from the system of the female in whom it 

 resides, or from that of the man with whom she 

 cohabits, so that the tendency to disease or 

 malformation sometimes precedes the first im- 

 pulse that leads to the establishment of life. 

 Another source of abnormal conditions in the 

 fetus occurs in the cohesion or intus-susception 

 of germs, in consequence of more than one 

 ovulum being contained within the same vesi- 

 cle ; under which circumstances unnatural 

 union may take place between two fetuses, 

 and give rise to the production of such anoma- 

 lies in organization as the Siamese twins, or to 

 other forms of fetal duplicity, more or less re- 

 sembling the remarkable instance represented 

 in the annexed sketch of two children born a 



* See several instances recorded by Mauriceau, 

 Malad. des femmes grosses, vol. ii. obs. 439, 497, 

 530, 622, 629, 656. 



few years since at Boyle, in the county of Ros- 

 common. 



Fig. 146. 



They were born alive, and lived for more 

 than a week ; after death they were sold to the 

 College of Surgeons in Dublin, in whose mag- 

 nificent Museum a preparation of their skeleton 

 is preserved.* The writer lately received from 

 the President of the College of Physicians, Dr. 

 Croker, two hen's eggs united at their end by 

 a connecting stalk as thick as one's little finger, 

 which, in common with the two eggs, was 

 covered by a tough white membrane. 



From intus-susception of one germ within 

 another, arise also some very singular pheno- 

 mena, such as the existence of perfect teeth set 

 in bony sockets, long hair, &c. in situations 

 far remote from those in which such structures 

 are naturally formed ; and the still more extra- 

 ordinary fact of fetuses being found within the 

 bodies of males ;f facts which, in the opinion 

 of the writer, can be explained only on the 

 supposition of original intus-susception of 

 germs, constituting that abnormal condition 

 which has been called monstrosity by inclu- 

 sion ;J an accident which appears to be by no 

 means confined to the germs of the mammalia 

 nor even of the animal kingdom. The writer 

 has in his museum a small egg about as large 

 as a gooseberry, which was found within ano- 

 ther egg of the common hen, which also oc- 

 curred to Harvey , who says, " I have seen an 

 exceeding small egge, which had a shell of its 

 own, and yet was contained within another 

 egge, greater and fairer than it, which egge also 

 had a shell too. And this egge I shewed King 

 Charles my most gracious master in presence 



* See also case by Dr. Alcock in Dublin Medical 

 Essays, vol. ii. p. 33, and Hall on the Czesarean 

 operation, p. 470. 



t Med. Chir. Trans, vol. i. p. 234, case of a 

 fffitus found in a young man, by Nathaniel High- 

 more, 1815. 



{ See Archives Generates de Medecine, torn. vii. 

 p. 355. 



Exercitation xi. pp. 50, 51 Ent's translation. 



