Heredity and the Law of Evolution. 291 



of the nearest relatives. In Syria consanguineous marriages were 

 common, at least in the reigning families, from the earliest times 

 down to the end of the Seleucidae. As for savage races, such 

 as the Samoiedes, Tartars, Caribs, American Indians, etc., their 

 customs in one place allow such marriages, in another proscribe 

 them. Passing from the practical domain of customs to the 

 theoretic domain of science, we meet with the same state of 

 indecision. 1 



According to Danvin, the consequences of close interbreeding 

 in animals, carried on for too long a time, are generally believed 

 to be loss of size, of vigour, and of fertility. He cites the opinions 

 of several breeders in confirmation of this. Yet 'with cattle there 

 can be no doubt that close interbreeding may be long carried on 

 advantageously with respect to external characters, and with no 

 manifestly apparent evil as far as constitution is concerned.' 

 Bates, a well-known breeder, says that 'interbreeding with bad 

 stock is ruinous and disastrous, but with first class cattle it may 

 be practised safely within certain limits/ A flock of sheep has 

 been kept up, in France, during sixty years without the intro- 

 duction of a single strange ram. With pigs on the other hand 

 long continued interbreeding is attended with the most disastrous 

 results. ' Mr. J. Wright, well known as a breeder, crossed a boar 

 with his daughter, granddaughter, and great-granddaughter, and so 

 on for seven generations ; the result was, that in many instances 

 the offspring were sterile, others died, and among those which 

 survived a certain number were idiotic, incapable of sucking, or 

 walking straight.' As regards birds, Darwin finds a considerable 

 number of proofs which condemn unions between the same blood. 

 He refuses to consider the question as it concerns man, ' since it 

 is there surrounded by prejudice/ still he seems not to be in favour 

 of consanguineous marriages. 



Other authors condemn them without reserve, among these 

 Prosper Lucas and Dr. Boudin. The latter, taking his stand on a 

 great number of facts and figures, considers them as the undoubted 

 cause of very many morbid phenomena, several of which concern 



1 Lucas, vol. ii. p. 903 ; Bulletins de la Soctitt d? Anthropologie, vols. i. iii. 

 iv. and vi. ; Darwin, Variation, etc., vol. ii. ch. xvii. 



