In Germany, according to the tables of _Krieger_ and _L. Mayer_, who
have recorded 11,500 cases in all, menstruation begins most commonly (in
18.931 per cent. of the cases) at the age of 15; the next most frequent
age is 14 (18.213 per cent. of the cases).
For Berlin, in a number of cases collected from the lower classes of
society, we find the average age for the first appearance of
menstruation to be 16.18 years.
Notwithstanding the more northerly situation of Berlin, the average age
at puberty is somewhat less than in Munich, situated 4½ degrees to the
southward, for the reason that the retardation dependent upon altitude
makes itself manifest in the latter town, which is situate about 500
metres (1,640 feet) higher above the sea level. Whereas in Berlin 18 per
cent. of all cases begin to menstruate at the age of 14, and 19 per
cent. at the age of 15, in Munich the two leading years are 15 with a
percentage of 17½, and 16 with a percentage of 18¾.
In Great Britain, according to _Krieger_, the average age at which
menstruation begins is 15 years, 1 month, and 5 days. For Manchester the
age given is 15 years, 6 months, and 23 days. In France, according to
the calculation of _Brierre de Boismont_, the most frequent age for the
first onset of menstruation is 16. In Paris the average age is 14 years,
6 months, and 14 days. Bohemia, Upper and Lower Austria, and Moravia
have an average age of 16 years and 2 to 3 months.