has as yet been done in this country. Professor Richmond Mayo-Smith estimated that marriages between near kin constituted less than one per cent of the total,[14] and Dr.

what spasmodically and inaccurately. According to Mulhall[16] the ratio of the

bl

atio. Coun

67 Als

69 Fra

d 75 J

d nearer.[17] Dr. Peer says that 4 per cent of the marriages in Saxony are consanguineous.[18] The rat

LE

atio.[A] Country

60 97 France

65 143 Alsac

71 84 Italy

er 10

rent parts of the country. Mulhall gives t

LE

io.[A] Provin

24 Si

30 Pied

100 Lig

er 10

arge. Wherever statistics have been gathered it is the rule that the percentage of consanguineous marr

LE

ural. Urba

nd 79

130 1

e 121

Uchermann)

des secon

ned 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 we

BL

an. Rural.

d aunt 1.

niece 6.

" 96.0 1

03.6 12

anguineous marriages 92 per cent were of cousins and 8

hat in Paris the records are well kept. He found that in the years 1853-62 there

tween cousin

etween uncl

etween aunt

nsanguin

examples of the carelessness and incompetency of the rural record keepers, and insists that the percentage is really much higher than the off

, to eliminate this element of chance, he obtained from the Registrar General's Report the frequency of occurrence of the various surnames in England. The fifty commonest names embraced 18 per cent of the population. One person in every 73 was a Smith, one in every 76 a Jones and so on. Then the probability of a Smith-Smith marriage due to mere chance would be 1/732 and of a Jones-Jones marria

3. Of the 18,528 marriages there found, 232 or 1.25 per cent were between persons of the same surname. Deducting the

urname, and exactly half of these were first cousins. In the "English and Irish Peerage" out of 1,989 marriages, 18 or .91 per cent were same-name first cousin marriages. He then sent out

irst cousin

e first cousi

first cousin

lculated to be 3.41 per cent of all marriages

ll these sources Mr. Darwin ob

first cous

name marr

=

lower and perhaps .50 instead of .57. By a simi

first cousi

first cousin

lculation he obtains by one method the ratio 2/7, and by another 1/1. He fi

first cous

cousin mar

ed formula

e-name

cousin mar

X

35 (n

Mr. Darwin computes the percentages of first cous

don

ban dist

distri

s and Lande

ocrac

names embraced nearly 15 per cent of the whole (1526), or three per cent less than the number found by Darwin.[26] Of these, one in every 53 was a Smith, one in 192 a Lawrence, and so on. The sum of the fraction 1/532, 1/192

high, so in the hope of finding the fallacy, I worked out the formula entirely from American data. To avoid the personal equation which would tend to increase the number of same-name first cousin marriages at the expense of the same-name no

first cous

ame marria

=

of all same-name marriages are first cousin marriages. Taking data from the same sources and eli

first cousin

first cousin

= _

12 =

.

n-relatives, why should we not assume that the attraction between cousins of the same surname should exceed that between cousins of different surnames? For among a large number of cousins a person is likely to be thrown into closer contact, and to feel better acquainted with th

e-name ma

cousin mar

X

=

f Mr. Dar

r dent of same-name marriages, and dividing by .75 w

84 per cent were between persons of the same surname. Applying the same formula as before, we find 1.12 per cent of first cousin marriages, or less than half the percentage found in eighteenth-century New York. This difference may easily be accounte

ound the total to be 25,200. From these sixteen families I obtained 153 cases of first cousin marriage, or .6 per cent. Allowing for the possible cases of cousin marriag

he records of 7500 marriages in that family, of which 57 or .8 per cent are same-

ir circle of acquaintance is very limited, and cousin marriage is therefore more frequent. If we exclude such places, and consider only the more progressive American communities, it i

are probably much too large. Applying

LE

Per cent of same-name marriages.

litan Districts

ricts 22,3

ricts 13,3

8,892 .

, .75 per cent,

st cousins figures are still more difficult to obtain. The distribution

LE

cond cousins 2-1/2 cousins Thi

70 24 49 1

me 96 30 58

54 107 4

more marriages between first cousins than between those of any other recognized degree of consanguinity. But the two degrees of 1-1/2 cousins and second cousins taken together probably number more intermarriages than first cousins alone. Allowing four children to a family, three of whom marry and have families, the actual

those genealogies in which only the male

LE

cond cousins 2-1/2 cousins Thi

e 24 5 1

me 62 15 33

20 43 16

s the tendency for families of the same name to hold together even in migration as may be proved by the strong predominance of certain surnames in nearly every community. So that the ratio or same-name to different-name second cousin marriage may not greatly exceed 1:4. Beyond this

ages of either the next nearer or more remote degrees. For example, a man is more likely to marry his first or his second cousin than eit

equency of consanguineous marriage in the

in the northern and western states to 5 per cent, and probably higher, in isolated mountain or island commu

with the increasing ease of communication and is probably le

ly somewhat less than the number of marriages between first cousins, but the number of second cousin marriages combined with the number of 1-1/2 cousin marriages probably

25, of which 15 per cent does not marry, leaving an average of 2.3 children in every family who marry. On this basis a person would have at birth 4,357 relatives within the degree of fourth cousins; at the age of 33 he would have 4,547; and at 66, 5,002. In 1897 out of 229,041 marriages in Italy, 1,046 were between first cousins, giving an average of one in 219. In 1881 the number of men between 18 and 50 and of women between 15 and 45 was 5,941, 495 in 8,259 communes with an average population of 3,500. In each commune there m