[Footnote 15: _Effect of Consanguinity upon the Organs of Special
Sense_, p. 4.]

In several European countries such marriages have been registered,
though somewhat spasmodically and inaccurately. According to
Mulhall[16] the ratio of the consanguineous among 10,000 marriages in
the various countries is as follows:

TABLE I.
-----------------------------------
Country.| Ratio. | Country.| Ratio.
-----------------------------------
Prussia | 67 | Alsace | 107
Italy | 69 | France | 126
England | 75 | Jews | 230
-----------------------------------

[Footnote 16: _Dictionary of Statistics_, p. 383.]

According to Uchermann the ratio is 690 or 6.9 per cent, including
marriages between second cousins and nearer.[17] Dr. Peer says that 4
per cent of the marriages in Saxony are consanguineous.[18] The ratio
seems to be increasing in France but diminishing in Alsace and Italy,
as indicated in Table II.[19]

[Footnote 17: _Les Sourds-muets en Norvège_. Quoted by Feer, p. 9.]

[Footnote 18: _Der Einfluss der Blutsverwandschaft der Eltern auf die
Kinder_, p. 9.]