184 Pigmentation Survey of School Children in Scotland 
greater than in the case of dark hair, and nearly as great as in the case of jet 
black hair. The odds against a less correlation than that found are so great as 
to warrant the conclusion that blue eyes are far more common where Gaelic is 
spoken than where it is not. Medium eyes are distinctly correlated negatively 
to the Gaelic speaking population. One may safely conclude that medium eyes 
are rarer in Gaelic speaking regions than in the rest of the country. Medium 
hair, and in a lesser degree dark eyes, are also negatively correlated to the Gaelic 
speaking population, the correlations being appreciable in each case, but fair 
hair, red hair and light eyes are present in practically the same proportions in 
both the Gaelic and non-Gaelic speaking populations. Thus, on a direct survey 
of the Gaelic speaking population, one would expect the group to be much darker 
in hair colour and more blue eyed per.sons would be expected among the Gaelic 
speaking than in the remaining population, the excess being accompanied by lesser 
proportions of medium hair and medium eyes and also dark eyes. No sensible 
dififei'ences would be expected in the fair-haired, red-haired, and light-eyed classes 
compared with the general population. Tlie definite relationship between the 
Gaelic speaking population and certain colour classes now established, enables one 
to interpret more fully the meaning of the significant differences in the western 
portion of Scotland. In Table XXX. it is seen that the North-Western, West- 
Midland and South-Western divisions are the only ones in which there is an excess 
of Gaelic speaking persons over the general average. In these divisions about 
65 per cent, in Sutherland and about 50 per cent, in each of the counties of 
Ross and Cromarty, Inverness and Argyll speak Gaelic. So far as hair colour is 
concerned, all these counties show great excess of dark and jet black hair. This 
excess is therefoi-e due mainly to the Gaelic speaking populations in these counties. 
Light eyes, although in excess in Argyll, are neither peculiar to the Gaelic 
speaking population nor to the non-Gaelic speaking population, since the value of 
the correlation coefficient is a very small one. The one group is likely to have 
as large a proportion of light eyes as the other. But blue eyes are associated even 
more intensely with Gaelic speaking people than dark hair, and this class is in 
excess in Sutherland, Ross and Cromarty, Inverness and the Western Isles. A 
fairly large proportion of the dark-haired Gaelic speaking people have therefore 
blue eyes. In these counties, however, fair hair is also in excess, and since the 
Northern Isles, Orkney and Shetland, are characterised by a large excess of fair 
hair and blue eyes and by an exceedingly small proportion of Gaelic speaking 
people, one would infer that blue eyes are largely associated with fair hair in the 
non-Gaelic portion of the population of these counties as well. Thus these counties 
consist of a mixture of fair-haired, blue-eyed, or blonde non-Gaelic speaking popu- 
lation (or if Gaelic speaking, at least of non-Keltic origin) and a dark-haired 
Gaelic speaking population. The distribution of eye colour in this latter population 
is unknown, but all classes of eyes are most probably represented, a fairly large 
proportion of blue eyes being quite certain. 
