350 GENERATION. 



female, which is called a free-martin, is sterile, and presents 

 an imperfect development of the internal organs of genera- 

 tion. 1 This has led to the idea that possibly the same law 

 may apply to the human subject, in cases of twins, one male 

 and the other female ; but numerous observations are recorded 

 in gynaecological works, showing the incorrectness of this 

 view, to which we may add the following : The author of the 

 report on Rinderpest to the New York State Agricultural 

 Society, 186T, stated that his father was one of twins, male 

 and female, and that his father's twin sister had borne sev- 

 eral children. 



It has long been a question whether impressions made on 

 the nervous system of the mother can exert an influence upon 

 the foetus in utero. While many authors admit that violent 

 emotions experienced by the mother may affect the nutrition 

 and the general development of the foetus, some writers of 

 high authority deny that the imagination can have any influ- 

 ence in producing deformities. 3 It must be admitted that 

 many of the remarkable cases recorded in works on physi- 

 ology as instances of deformity due to the influence of the 

 maternal mind are not reliable. It is often the case that, 

 When a child is born with a deformity, the mother imagines 

 she can explain it by some impression received during 

 pregnancy, which she only recalls after she knows that the 

 child is deformed. Still, there are cases which cannot be 

 doubted, but which, in the present state of our knowledge of 

 development and the connection between the mother and the 

 foetus, we cannot attempt to explain. Prof. Dalton, whose 

 accuracy upon such a point cannot be questioned, noted the 

 following : While he was lecturing upon the subject of gen- 

 eration at the College of Physicians and Surgeons of New 

 York, the janitor of the college called his attention to his 

 child, which presented a deformity of the external ear, as 



1 See page 303. 



2 ISIDORE GEOFFREY SAINT-HILAIRE, Anomalies de V organization chez 

 et Us animaux, Bruxelles, 1837, tome iii., p. 391. 



