TERATOLOGY. 



945 



palate is attributed by Tieclemann to the 

 original absence of olfactory nerves. G. 

 Vrohk found them, however, in children with 

 hare-lip. The nerves of organs may exist, 

 although the organs themselves may be ab- 

 sent (Seller, W. Vrolik); and inversely, the 

 nerves may be wanting, while the organs are 

 present (C. G. Buttner). In anencephali the 

 body is very massive, notwithstanding the 

 imperfect condition of the nervous centres. 

 In double monsters there is no definite corre- 

 spondence between the condition of the nerv- 

 ous system and the duplication of the body 

 (W. Vrolik).* 



b. Embryogenesis teaches that the forma- 

 tion of the several parts of the body is not 

 essentially the result of that of the nervous 

 system, but that, on the contrary, each part 

 is formed and developed independently. I 

 refer to what I have already said, in 1836 (in 

 my treatise on Cydopid), and am happy to 

 find J. Muller, llathke, Bischoff, Burdach, 

 and Stannius, with me on this subject. 



What is now proved for the nervous system, 

 may equally be applied to the system of blood- 

 vessels; and hence I presume to conclude, 

 that no malformation whatever proceeds from 

 a central system, but is occasioned merely by 

 impeded developement, the cause of which 

 remains concealed. This impediment may be 

 confined to one part, or may be extended 

 over more. This extension may sometimes 

 stand* either in causal connexion with an 

 original malformation, as for instance the dis- 

 placing of the nose in cyclopes ; or may take 

 place in an entirely independent manner. 

 IP. the latter case, it is a complication of mal- 

 formation, which proves that it may extend 

 itself to more than one region of the body, 

 and to more than one apparatus. I have 

 met with an instance of this, in which to 

 acrania, cyclopia, and absence of the lower 

 jaw, was added ectopia of the intestines. If 

 the origin of the malformation is derived from 

 impeded developement, the so-called monstra 

 per defectum are the result, and from excessive 

 formation arise the monstra per excessum. 



The malformations occasioned by impeded 

 developement may, for the most part, be com- 

 pared with the natural forms through which 

 the foetus passes in its normal developement. 

 On this is founded the ingenious idea of 

 Meckel, previously suggested by Wolff, that 

 most malformations are caused by arrest of 

 developement (bildungshemmung), for which 

 reason they must be said, according to 

 Bischoff, to be formed through arrested de- 

 velopcmcnt (JiemmungsbUdungen). They, how- 

 ever, never give us a perfect representation 

 of the form at which the foetus has been 

 arrested in its developement, because the in- 

 creased growth and the progressive nutrition 

 of the fcetus cannot but make an important 



* On this subject I have given copious elucida- 

 tion in the Treatise on Cyclopia in Transactions of 

 the First Class of the Royal Netherland Institute, 

 1-836, vol v. p. 25. ; on Double Monsters, ibid. 1840, 

 vol. ix. ; and Handbuch, vol. i. 1840. 



VOL. IV, 



modification therein. As the transient forms 

 of the human foetus are for the most part 

 comparable to the persistent forms of the 

 lower animals, the malformations occasioned 

 by impeded developement often acquire a 

 brute appearance ; and thus a reason is at 

 the same time given why they exhibit, in dif- 

 ferent animals, the form of the lower, but not 

 of the higher classes. 



A consequence of this mode of origin is, 

 that they never deviate so much from the 

 normal form as would exclude them from the 

 rank of organized beings ; and that the devia- 

 tions from the natural form are confined 

 within definite limits, so that they always re- 

 remind us more or less of the regular form. 

 Fixed laws of organization prevail in them, 

 by which they exhibit a certain fitness of 

 organization, and a tendency to render the 

 capacity for life as great as possible, not- 

 withstanding the malformation. Peculiar vi- 

 tal relations are hereby produced adapting 

 them for uterine life, and many are brought 

 forth well nourished and at full time. Most, 

 however, are unfit for life after birth, though 

 for very different reasons. 



The following remarks may serve for the 

 elucidation of these peculiar vital accommo- 

 dations : 



1. We never see in malformed births, dis- 

 similar parts fused or united with each other, 

 such as the intestinal tube with the aorta, 

 the arteries with the nerves, &c. Each 

 part, therefore, retains, to a certain degree, its 

 own independence, according to what Fleisch- 

 mann denominates lex proprietatis. The gullet 

 sometimes coalesces with the larynx, and the 

 bladder with the rectum ; but these parts are 

 not originally dissimilar, being developed from 

 a common mass. 



2. The malformed parts are restricted to 

 their determinate place, according to what 

 Fleischmann denominates lex topicorum. 



3. No malformed organ loses entirely its 

 own character, and no malformed animal loses 

 its generic distinction. It is, therefore, justly 

 observed by Soemmering, that nature does not 

 deviate ad infnitum, and that even in mon- 

 strosities a distinct gradation and natural or- 

 der are observable. 



An immediate consequence of this must be, 

 that in one and the same sort of monstrosity, 

 there are different degrees of malformation, 

 varying from the greatest possible degree to 

 the very least. We might thus consider the 

 different monstrosities as so many genera, and 

 their varieties as so many species, where- 

 by, according to J. T. Meckel, a new or- 

 ganic kingdom is constituted, differing only 

 from the others by less constancy of form. 

 Consequently a definite type prevails in the 

 generation of monstrosities, and they are 

 subjected to fixed organic laws. This order 

 appears even 1. In the number in which 

 they occur within a certain space of time. In 

 3000 births in Paris, there occurs about one 

 monster (J. Geoflfroy St. Hilaire). 2. In 

 the sex. In impeded developement, the mal- 

 formed children are more frequently female, 



3 p 



