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 |
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]]
| TABLE II. | |||||
|---|---|---|---|---|---|
| Country. | Date. | Ratio.[A] | Country. | Date. | Ratio.[A] |
| France | 1853-60 | 97 | France | 1861-71 | 126 |
| Alsace | 1858-65 | 143 | Alsace | 1872-75 | 107 |
| Italy | 1868-71 | 84 | Italy | 1872-75 | 69 |
| [A] Per 10,000. | |||||
In Italy the ratio varies greatly in different parts of the country. Mulhall gives the following figures for the years 1872-75:
| TABLE III. | |||
|---|---|---|---|
| Province. | Ratio.[A] | Province. | Ratio.[A] |
| Venice | 24 | Sicily | 117 |
| Naples | 30 | Piedmont | 131 |
| Lombardy | 100 | Liguria | 183 |
| [A] Per 10,000. | |||
It will be noted that the lowest ratios are in provinces where the urban population is comparatively large. Wherever statistics have been gathered it is the rule that the percentage of consanguineous marriage is greater in rural than in urban districts. Table IV, also from Mulhall, illustrates this point.
| TABLE IV. | |||
|---|---|---|---|
| Country. | Rural. | Urban. | General. |
| England | 79 | 71 | 75 |
| France | 130 | 115 | 126 |
| Alsace | 121 | 41 | 107 |
| Norway[A] (Uchermann) | 810 | 260 | 690 |
| [A] Includes second cousins. | |||
In regard to the degree of consanguinity, it seems very probable that in the French, German, Italian, and English statistics and estimates few if any marriages beyond the degree of first cousins are returned as consanguineous, so in order to compare the Norwegian figures with the others they should probably be reduced by one half. Out of 1549 consanguineous marriages contracted in Prussia in 1889, 1422 were between "cousins" (probably first), 110 between uncles and nieces, and 16 between nephews and aunts.[[20]] The ratio of such marriages to 10,000 in France during the fifteen years ending in 1875 was:[[21]]
| TABLE V. | |||
|---|---|---|---|
| Degree. | Urban. | Rural. | All France. |
| Nephew and aunt | 1.6 | 2.4 | 2.1 |
| Uncle and niece | 6.0 | 5.6 | 5.8 |
| "Cousins" | 96.0 | 119.0 | 113.1 |
| Total | 103.6 | 127.0 | 121.2 |