rn United States, H. J. Banker found[123] that the
number of children declined with each decade. Thus married women
graduates prior to the Civil War had 2 surviving children each; in the
last decade of the nineteenth century they had only one. For married men
graduates, the number of surviving children had fallen in the same
length of time from 2.62 to 1.38. When all graduates, married or not,
are counted in the decade 1892-1901, it is found that the men of
Syracuse have contributed to the next generation one surviving child
each, the women only half a child apiece.

Dr. Cattell's investigation of the families of 1,000 contemporary
American men of science all of which were probably not complete however,
shows that they leave, on the average, less than two surviving children.
Only one family in 75 is larger than six, and 22% of them are childless.
Obviously, as far as those families are concerned, there will be fewer
men of inherent scientific eminence in the next generation than in this.

The decline in the birth-rate is sometimes attributed to the fact that
people as a whole are marrying later than they used to; we have already
shown that this idea is, on the whole, false. The idea that people as a
whole are marrying less than they used to is also, as we have shown,
mistaken. The decline in the general birth-rate can be attributed to
only one fact, and that is that married people are having fewer
children.

The percentage of childless wives in the American stock is steadily
increasing. Dr. Crum's figures show the following percentage of
childless wives, in the New England genealogies with which he worked:

1750-1799 1.88
1800-1849 4.07
1850-1869 5.91
1870-1879 8.10

J. A. Hill[124] found, from the 1910 census figures, that one in eight
of the native-born wives is childless, as compared with one in five
among the Negroes, one in nineteen among the foreign born. Childlessness
of American wives is therefore a considerable, although not a
preponderant factor, in this decline of the birth rate.

Dr. Hill further found that from 10 marriages, in various stocks, the
following numbers of children could be expected:

Native-born women 27
Negro-born women 31
English-born women 34
Russian-born women 54
French Canada-born women 56
Polish-born women 62

The women of the old American stock are on the whole more sterile or, if
no