On Ncevi Maiemi, 35 



411 the same direction with dlfiferenl velocities ; that with 

 the {greater velocity, on overtaking the other, cominunicatea 

 part of its force^ and of course loses, so much in its ve- 

 locity. 



V. On Ncevi Materni. 



To Mr,, Tilloch. 



tt-R, 1 HE last Number of your Philosophical Magazine 

 contains a discussion, by one of your ingenious correspon- 

 dents, in support of the old prejudice that certain congeni- 

 tal marks or excrescences, commonly called 7icBvi materni, 

 originate from the influence of the mind of the parent-. As 

 the paper, no doubt, vvas written with a serious object, I 

 comply with the writer's request in forwarding 'to you for 

 publication some observations on the subject. 



It is agreed that ncevi materni resemble known objects m 

 nothing more thanyb?^; although, as Enceps (the wri*- 

 ter's signature) observes, " more than one volume has been 

 filled with reputed instances of the effects of the mother's 

 imagination upon her olTspring." The/orm^, however, of 

 vcevi materni in general are so far from having a resem- 

 blance to any known object^ that the experience of practi- 

 tioners, who are in the daily habits of operating on some, 

 and seeing many others, proves as much as extensive ex- 

 perience can prove, that the relations of Ticevi materni re- 

 sembling a bunch of grapes, or a bit of bacon, are to be 

 classed with tne idle tales of the nursery. Even Enceps 

 himself '^ vvas for a long time prepossessed with the same 

 notion,'' viz. that such fanciiul forms of ncevi materni were 

 ^* idle tales,*' till a case " was related to him by an mtelligent 

 friend who had seen a child born with only one leg, as 

 well as its mother, who declared her firm belief that the 

 cause of this imperfection in her child was a violent fright 

 which she experienced from seeing a beggar suddenly un- 

 'cover the wounded slump of his thigh." This, however, 

 is not an example of nceuvs- maternus, but ot monstrosity, 

 Kow 1 will seriously ask Euceps, at what period of preg- 

 nancy this unfortunai.e mother received such a violent 

 fright. In the latter mc^nths of pregnancy, ry/ifer. the limbs of 

 the fcetus had been formed? The separation of a limb, 

 and its siill more extraordinary annihilation, must then be 

 explained as the efiects of imagination, — or in the early 

 months of pregnancy, lefur@ the ovum had become organ- 



C2 ized] 



