A. M. Carr Saunders 
357 
The comparison of the hair colour percentages of children aged 13 and those 
aged 3—7 shows no very considerable change. There is a certain darkening of 
the hair, but it is not very pronounced*. The percentage of fair haired children 
is actually higher amoug those of 13 years of age than among the younger children. 
The chief change is a gain of the .Dark Brown class at the expense of the Light and 
Medium Brown classes. 
TABLE III. 
Percentage of Eye Colour Groups to the Total. 
Eye 
Colour 
Boys. Age 13 
Gtuls. Age 13 
Boys. Age 3 — 7 
Girls. Age 3 — 7 
Numbers 
Per- 
centage 
Numbers 
Per- 
centage 
Numbers 
Per- 
centage 
Numbers 
Per- 
centage 
Blue ... 
Light ... 
Neutral 
Dark ... 
354 
568 
544 
528 
17-76 
28-49 
27-28 
26-47 
385 
577 
564 
561 
18-45 
27-65 
27-02 
26-88 
208 
58 
89 
.115 
44-26 
12-34 
18-94 
24-46 
173 
48 
64 
75 
48-06 
13-33 
17-78 
20-83 
Totals 
1994 
100-0 
2087 
100-0 
470 
100-0 
360 
100-0 
Table III shows that for the older children the classification adopted for eye 
colour provides a fairly equal division into the four categories. A direct com- 
parison with the Scottish figures is here possible since presumably the medium class 
in one case is identical with the neutral class in the other. The percentage of 
blue eyed children is distinctly higher in our data; and this is remarkable since 
the darker type of eye is more frequent in Scotland ; and, further, Tocher's data 
give a higher percentage of blue eyes than is usually found. The suggestion is 
that at Birmingham the classification of blue eyes has not been very strict, and 
that a number of light blue eyes have been admitted into the blue eye category 
when they should have been placed in the light category. This idea is supported 
by the figures given for the children aged 3 — 7. In this case the blue eyed 
children amount to nearly 50 per cent, of the total. This is almost certainly 
too high a total, if the term blue eye is to be used in its usual meaning. Among 
the younger children the percentage of light eyes falls rather low ; and probably a 
considerable number of the blue eyes should have been included in the light eyed 
class. The table is noteworthy as marking a very considerable change with age to 
the darker eye classes. 
Table IV shows the average number of diseases per child in each hair category. 
The hair categories have also been combined into two larger groups — roughly 
representing light and dark hair — and the average number of diseases for these 
groups has been worked out. Further figures are also given to show the average 
number of diseases per boy and girl in the different age groups. 
* For estimates of the correlation between hair colour and age, see Biometrika, Vol. in. p. 462. 
