THE REPRODUCTIVE SYSTEM. 59 



ration been observed. From a parity of reasoning, as we know 

 that an insuperable bar has been placed against propagation 

 among the several genera, by an instinctive aversion that the 

 specific forms might not be lost in hybridous productions ; so it 

 does not appear to be straining analogy too much to suppose that, 

 had ill eflfects followed from consanguineous intercourse, something 

 like this instinctive aversion would be manifested here also^o. 

 Neither does it appear, a priori^ easy to substantiate either moral 

 or physiological reasons why breeding among lineal kindred should 

 of necessity prove deteriorating to the future progeny, when no 

 family departure from the original type is apparent. The same 

 organization, the same constitutional sympathies, the same apti- 

 tudes, when not defective, would tend, under union, to produce a 

 perfect similitude : but facts are infinitely more to our purpose 

 than the most specious argvunents. 



We are assured, that the Arab horses of high blood are 

 usually bred in-and-in ; and we know that no pepple in existence 



remarked, that, when this island was conquered by Caesar, a peculiar system of 

 cohabitation prevailed. — Uxores habent deni duodenique inter se commvmes, 

 et maxime fratres cum fratribus, parentesque cum liberis ; sed si qui s\mt ex 

 his nati, eorum habentur liberi, quo primum^ vurgo quaeque deducta est; — 

 Paley^s Nat. Hist. 



■ ^ It may be argued, that such aversion is manifested in the political restric- 

 tions relative to consanguineous marriages among enlightened nations. That 

 such prohibitions were necessary from moral and political necessity is evident; 

 for, by extending the social compact to marriages without the family pale, 

 knowledge and the arts were extended, improved, and became a common pro- 

 perty ; wealth was diffused, communities were enlarged, and social interests 

 joined those who before were in opposition to each other; and, above all, 

 the demoralizing and depopulating effects of an early departure from chastity, 

 which imreserved family communication led to, was prevented. It is, how- 

 ever, clear, from history aad from phUosc^hical investigation, that such 

 aversion is neither instinctive nor necessary, but an acquired regulation of 

 passion, implanted by education, and made general by refinement Sir W. 

 C — N observes that, according to Varro, this aversion has really occurred even 

 in animals, — Equus matrem ut saliret adduci non posset, De Re Rustica, lib. 

 iii, c. 5 ; but the ingenious Baronet candidly acknowledges that subsequent 

 experience has not justified the assertion. 



