

124 



GOOD FROM CROSSING. 



Chap. XVII 



The 



thus unconsciously have acquired their dislike and even abhor 



rence of incestuous marriages, rather than that they should hav< 



discovered by reasoning and obse 



abhorrence occasionally failino- is 



feeling being instinctive, for any instinct may occasionally fail 



or become vitiated, as sometimes occurs with parental love and 



the social sympathies. 



o 



'to 



follows from 



be answered by 



In the case of man, the question 



interbreeding will probably ne 



he propagates his kind 



slowly and cannot be subjected to experiment ; but 

 universal practice of all races at all times of avoiding closely- 

 related marriages is an argument of considerable weight • and 



wlmtever conclusion we arrive at in regard to the higher animals 

 may be safely extended to man. 



< Turning now to Birds : in the case of the Fowl a whole array of autho- 

 rities could be given against too close interbreeding. Sir J. Sebright posi- 

 tively asserts that he made many trials, and that his fowls, when thus 

 treated, became long in the legs, small in the body, and bad breeders 25 

 He produced the famous Sebright Bantams by complicated crosses, and by 

 breeding in-and-in ; and since his time there has been much close inter- 

 breeding with these Bantams ; and they are now notoriously bad breeders. 

 I have seen Silver Bantams, directly descended from his stock, which had 

 become almost as barren as hybrids ; for not a single chicken had been 

 that year hatched from two full nests of eggs. Mr. Hewitt says that with 

 these Bantams the sterility of the male stands, with rare exceptions, in the 

 closest relation with their loss of certain secondary male characters : he 

 adds, « I have noticed, as a general rule, that even the slightest deviation 

 « from feminine character in the tail of the male Sebright - say the 

 " elongation by only half an inch of the two principal tail-feathers 

 " brings with it improved probability of increased fertility. 



Mr 



states 27 that Mr 



a 



"26 



whose fighting-cotks were so 



(C 



" notorious, continued to breed from his own kind till they lost their dis- 

 " position to fight, but stood to be cut up without making any resistance, 

 " and were so reduced in size as to be under those weights required for 

 " the best prizes ; but on obtaining a cross from Mr. Leighton, they 

 " again resumed their former courage and weight," It should be borne 

 in mind that game-cocks before they fought were always weighed, so that 

 nothing was left to the imagination about any reduction or increase of 



(6 



25 « The Art of Improving the Breed/ 

 p. 13. 



26 ' The Poultry Book,' by W. B. 

 Tegetmeier, 1866, p. 245. 



27 * Journal Eoyal Agricult. Soc./ 

 1846, vol. vii. p. 205 ; see also Ferguson 

 on the Fowl, pp. 83, 317 ; see also ' The 



Poultry Book,' by Tegetmeier, 1866, p. 

 135, with respect to the extent to which 

 cock-fighters found that they could 

 venture to breed in-and-in, viz., occa- 

 sionally a hen with her own son ; " but 

 they were cautious not to repeat the 

 in-and-in breeding." 



