276 Duration of Marriage and Number of Offspring 
the reproductive period or who may have been separated from them otherwise. 
For women of the present generation marrying at the same age and under the 
same conditions we may make use of the regression formula from Table XXIII. — 
limiting the reproductive period to age 46 and adopting the average age at 
marriage as 18'G years (see Table XXVII.) we obtain 7"55. This is a reduction of 
about half a child per family. Adoptitjg the same principle the averages for the 
pi'esent generation are for age at marriage 20 — 25, 6'51, 25 — 30, 5"12, 30 — 35, 3"21, 
as against 6"90, 5*22 and 3'36 respectively for past generations. These differences 
are probably the extent of the regression. 
I have calculated from the information contained in the English Hegistrar- 
General's Reports the average age of spinsters marrying at ages under 4.5 for the 
years 1861-62 and 1901-2. The mean age at the former period was 243 years; 
at the latter 251 — an advance of nearly 1 ye.ir. This however hardly conveys an 
adequate idea of the change that lias taken place in England and Wales during 
the last forty years in the age constitution at marriage. At the former period 
only 30'9 per cent, were married after what may be regarded as the critical age 
(so far as fertility is concerned) of 25, whilst at the latter period the percentage 
had increased to 39'5. Having in view the rapid fall in the initial and subsequent 
fertility of marriages contracted beyond age 25 it is unquestionable that some not 
inconsiderable portion of the decline in the birthrate in England and Wales is due 
to the increasing age of spinsters at marriage. In Australian age at marriage 
statistics distinction is not made between first and subsequent marriages. 
In Victoria — which may be regarded as typical of Australia — the average age of 
all women marrying at ages under 45 was 241 years in 1875-6 ; in 1901-2 this had 
advanced to 25"6 years. At the former period 33 "8 per cent, were over 25 years of 
age, whilst at tlie latter the percentage had increased to 47"3. It would thus 
appear that there is a general tendency to postpone marriage both in England and 
Australia (probably more pronounced in the latter) and thus not only diminishing 
the average family but as we liave seen lengthening the intervals between the 
offspring. 
So long as the average age of the female at marriage is in the vicinity of 25 and 
there are no further restrictions of the family than at present the community 
will not be a loss for natural increase. The average family will — at the present 
Australian rate — be between 5 and 6 children, and although this is the gross family 
it must be borne in mind that the infantile — as well as the subsequent — mortality 
is very light when compared with Great Britain and European countries. Indeed 
the deaths of infiints form such a small percentage of the births — about 10 percent. — 
that the birthrate is considerably diminished thereby. And here (although not 
directly connected with this section of the investigation) it may not be out of place 
to refer to the correlation between the birthrate and the infantile mortality — the 
latter being the deaths under 1 year of age per 100 births. It will readily be seen 
from the next table of birthrates and infantile mortalities in various countries that 
