212 RELATION OF ORIGIN TO FERTILITY AND INFANT MORTALITY
proportions in the earlier years and then ceases for a period, the young adults marry and
the number of children increases very rapidly. Again, inequality of sex distribution tends
to lower the percentage under 10 years of age. In a population where large numbers of
men in a given stock are unmarried, the number of births would normally constitute a smaller
proportion of the total population. And finally, emigration would affect the proportions.
Unattached adults emigrate more readily than those with families. With thesz points in
mind, let us refer back to the two origin groups—the one group with the seven highest
percentages and the other with the seven lowest.
As to date of immigration, in no case has the proportion of an immigrant stock arriving
during the last seven years of the decade been significant. So, in all cases, the bulk of the
children under 10 years of age must be Canadian born. As to emigration, in all probability
the British stocks in Canada were affected by that to at least as great an extent as were
non-British and non-French stocks during the years prior to 1921. Such factors, then, were
aot of major importance in oecasioning the wide range of percentages under 10 years
of age In the various stocks in Canada in 1921.
The relation between the volume of immigrants prior to the war and the numbers
of a given stock resident in Canada is of greater significance. With the foreign stocks,
the inflowing stream of immigration constituted a much greater proportion of the total origin
group in Canada than with the British and French stocks. The effect of this difference was
‘0 produce an age distribution abnormally favourable to high fertility. With larger proporsions
 in’ the early adult and middle years of life in 1914, it is natural to expect larger
aumbers of children born during the subsequent years of the decade to the foreign born
parents of other than British and French stocks. How far tis influence explains the high
percentage under 10 years cannot be measured with the available data for 1921.
As against the favourable age distribution of the foreign stocks there are several
important influences especially unfavourable to natural increase. First, all the Eastern and
Central European stocks mentioned above show" much larger percentages of surplus males
chan the British stocks. Second, their infant mortality rates are much higher. Both
‘hese factors make for low percentages under 10 years of age.
We have, therefore, unfavourable sex distribution and high infant mortality rates tending
to neutralize favourable age distribution. In view of this compensating action, it would
appear that the high percentages under 10 years of age in the several stocks in the first
group are largely caused by abnormally high birth rates. In any cage, it is significant
that the combined effect of high birth rates and favourable age distribution has been
so great that, in spite of high infant mortality and unfavourable sex distribution, these
stocks show proportions under 10 years of age two-thirds larger than the British stocks.
The relative importance of fertility and age distribution of women between 15 and 49
years will be discussed below in reviewing the 1926 figures for the Prairie Provinces, but
sefore passing to that part of the analysis. a few additional points may be mentioned in
connection with Table 1831. The Italians, with an infant mortality rate somewhat larger
than that of the British stocks and with over twice as many adult males as females in
Canada, show 32.03 p.c. of their population under 10 years of age as against 21 p.c. for
‘he British. The Greeks, with between three and four times more males than females (21
years and over) and with an equally high infant mortality rate, had a percentage under
10 years one quarter larger than that for the British stocks. In the Japanese stock, with
two and a half times as many men as women, 24.03 p.c. of the total were below 10 years
of age. The proportions under 10 for the Scandinavian and Germanic peoples, on the other
hand, were only slightly above that for the British stocks.