NUMERICAL ANALY S IS OF TH E SERIES 47
Orthognathism and Prognathism
(in agreement with -
the Frankfort Convention)
Nasal Index
Cranial Capacity .
Hyperorthognathic, all below a ( — a ).
Orthognathic and Mesognathic, a to d inclusive.
Prognathic, from d e upwards.
Leptorhine, all below and including 47-9.
Mesorhine, 48 to 52-9.
Platyrhine, 53 and over.
Microcéphalie, all below and including 1349-9.
Mesocephalic, 1350 to 1449 9.
Megacephalic, 1450 and over.
With regard to this classification of the cranial capacity we have followed the
ordinary procedure, and have not attempted to establish a separate basis of classification
for males and females.
With a view to comparing the indices of the several periods the relative values of
these respective primary divisions were expressed in percentages, and the results are
tabulated both for males and for females in the accompanying Table (Table 1). The type
of the people of each period as given by the ‘ maximum of frequency ’ in each diagram is
entered in the same table. We are alive to the danger of laying too much emphasis on
this method of classification, but as in our other analyses we have adopted the ‘ arithmetical
mean ’ and the ‘ median ’ we thought that it might prove useful to give the ‘ maximum of
frequency ’ for purposes of comparison.
Classification
of features
according
to the
divisions
commonly
used in anthropometry.
Percentages
and Maxima
of Frequency.