The Marriage of Near Kin.

New Zealand Mail, Issue 889, 15 March 1889, Page 5

The Marriage of Near Kin.

There is a widespread idea that consanguineous unions produce either defective offspring or none at all. When a marriage between cousins is spoken of, sterility or a deaf-mute, idiotic, or deformed progeny is predicted, and examples are always at hand to cite in support of the prophecy. Does this opinion rest upon positive anu wellauthenticated facts, or is it erroneous ? This is a question that was examined a few years ago by Mr G. H. Darwin, who, after a profound study of the subject, came to the conclusion that, in the present state of science, there is nothing to justify the common prejudice that exists against the marriage of near kin. More recently, the subjeot has been further examined by Mr A. H. Huth, who has just published an exhaustive work upon it, in which he arrives at the same conclusion that Mr Darwin did. Mr Huth thinks that consanguinity of itself plays no particular role in the union of individuals of the same stook. In the descendants it increases the tendencies common to the two progenitors. By reason of their relationship, the closer this is and the closer the relationship of the ancestors, the greater is the tendency of the descendimts to exhibit the same dispositions. If these are good, consanguineous unions will b© advantageous, in that they will fortify and intensify them. If, on the contrary, they are bad, such unions should be avoided, in order to prevent a re-inforcement of unfavourable tendencies, which should be suppressed. But the case is identical where it

is a question of unrelated persons. No reasonable person would urge two neuropathic individuals of different families to unite, because he knows that the neurosis has every chance to become Intense in the descendants. On the contrary, a union between consanguineous individuals, equally healthy and well favoured, ought to be encouraged. What may be urged against marriages of near kin is the facility with which unfavourable tendencies are transmitted, and the relative rarity of the circumstances in which such marriages can really be advised. But, this admitted and explained, consanguinity of itself presents no inconvenience, especially if we consider how remote, by reason of the existing laws upon marriage, is'■ the degree of consanguinity between individuals capable of uniting legitimately. Upon the whole, consanguinity accumulates and intensifies tendencies. If these are bad, the marriage of near kin should be avoided; if good, it may be favoured. But as, unfortunately, the unfavourable tendencies are more easily and frequently transmitted, because they are the ones that are established with the most facility, there is oftener more reason for avoiding than seeking such unions. Upon the whole, Mr Huth concludes that the accusations directed against marriages of near kin are not. justified in the present state of science. -Scientific American.