The Occurrence of Twins in Successive 

 Generations. 



By Dr. W. J. RUTHERFURD. 



Pedigree A. 



The following Pedigree shows a decided tendency 

 to the production of twins in three succeeding generations. 

 It is but one of several of a similar nature which I have 

 been able to obtain.* 



In this Pedigree are twelve twin children, of whom 

 eight died in infancy or early childhood. This is a heavy 

 mortality and is doubtless significant of an inborn feeble- 

 ness of constitution. A glance at the Pedigree and at the 

 statement of facts will at once show that the greater part 

 of the stock here represented is to some extent degenerate. 

 Stillbirths, death with fits in infancy and other evidences 

 of nervous instability such as laryngismus stridulus, 

 taken together with vesical calculi and nephritis so 

 frequently recurring, is indicative of a sub-normal race. 



The person from Avhom the details of this clanship 

 were obtained realises that among her relations the first- 

 born children are not twins, but that these tend to be 

 produced towards the end of the family. There may or 

 may not be significance attaching to this, but that is a 

 question I propose discussing later on. 



The Facts of the Pedigree. 



Generation A. 



Nos. 1 and 2. Nothing of importance is known of 

 these two people. 



Generation B. 



No. 1. A daughter of Generation A. Died of 

 nephritis. Had only one child. 



* Dr. Rutherfurd tells me that in several instances, in both Pedigrees 

 A and B, he has had to rely upon the oral tradition of the family for his 

 information. — [Editor. ] 



