260 



The Journal of Heredity 



of parentage, and he describes the 

 people themselves as healthy, robust 

 and intelligent . The death-rate of those 

 who grew up was ver\^ low and man}' 

 of them lived to a great age. The 

 infant mortality, however, was very 

 high, chiefly from acute diseases of the 

 chest and throat and especially "croup." 

 It is of course ])ossible that amongst 

 these young children who succumbed 

 to acute infantile diseases there were 

 some who would have shown infe- 

 riorities or defects had they lived ; but 

 even if we grant that, it is difficult to 

 believe that not one of the survivors 

 would have suffered in some corre- 

 s])onding way. Nor does it seem likely 

 that the acute diseases of childhood 

 would have selected a specially large 

 projjortion of those who might after- 

 wards have shown degeneracies. 



A very similar account was given 

 in 1885 of the small fishing village of 

 Staithes between Whitby and Saltburn. 

 And quite a number of almost identical 

 ca.ses are upon record. 



Of course plenty of examples arc to 

 be found where an excessive proportion 

 of diseased and degenerate are found 

 amongst the offspring of cousin-parents. 

 But these prove no more than that if 

 such degeneracies exist in the stock 

 they may be transmitted. 



That inbreeding, very much closer 

 in degree and repeated far more often 

 than anything in modern human society, 

 does not necessarily lead to degeneracy 

 but quite the contrary is shown by the 

 history of modern breeds of domestic 

 animals. For it is of course admitted, 

 not only that the marvelous improve- 

 ments eff'ected during the last 150 years 

 in the breeds of horses, oxen, shec]:) and 

 jjigs — to name only the more imjjortant 

 kinds of live stock — have been reached 

 by careful selection of the individuals 

 possessing the characters desired; but 

 that, as we are constantly told, the 

 only way to secure and to fix such 

 desirable characters is to carry out this 

 crossing of near relations; i. e., we are 

 told that the desirable characters come 

 as the result of crossing parents both 

 f)f whcjm jjos-sess them in some degree. 

 Doubtless the same jjarents sometimes 

 also contain the rudiments of undesir- 



able characters and degeneracies also, 

 but such individuals will as far as pos- 

 sible not be used for breeding, and the 

 production of the weaknesses they show 

 will thus to a large extent be checked. 

 It may therefore be asserted that the 

 history of modern breeds of domesti- 

 cated animals affords little, if any, 

 support to the doctrine that marriages 

 of blood-relations can produce qualities 

 — good or bad— that are not repre- 

 sented at all in either parent. 



CLOSE IN-BREEDING 



There does, however, seem reason 

 to believe that fertility is, or may be, 

 diminished by very close in-breeding, 

 rc])eated for several generations (Dar- 

 win, Animals and Plants under Domesti- 

 cation, II., 101, etc.); I mean, e. g., by 

 mating, say, brother (a) with sister (6), 

 and sub.sequently the father (a) with 

 their daughter (d), and again with 

 her daughter (e) and so on or vice versa 

 as to sex. It is further asserted that 

 when such infertility has reached a 

 dangerous degree it can often be 

 counteracted, i. e., the normal fertility 

 of the race or species be restored, by 

 crossing with a non-related stock; or 

 what appears still more strange, by 

 crossing with a very distantly related 

 member of the same stock, — one derived 

 from another branch of the same 

 stem but perhaps reared under some- 

 what different conditions. We may 

 l)erhaps take comfort from this and — 

 whilst fully admitting that what is 

 true for some of the lower animals may 

 not always be true for man, especially 

 in regard to the higher and distinctively 

 human attributes, — conclude provision- 

 ally that if it should ever be shown that 

 human cousin marriages were less 

 ])rolific than others, this defect would 

 most likely Ix^ neutralized by the next 

 out-marriage. 



Huth ("The Marriage of Near Kin," 

 ])]). 193-96), .summing up the material 

 then available (1887) as to the number 

 of children born to parents who wore 

 blood-relations and to those that were 

 unrelated, res])ectively, found that the 

 consanguineous marriages a])i)eared to 

 be more fertile than the others; and 

 although he thinks tliat, owing to uncon- 



