J. F. Tocher ig9 
TABLE XXIII. 
Counties considered 
Persons per 
Square Mile 
Average Density of Population in non-divei'gent counties (Boys) 
» „ „ „ (Girls) 
Average Density' of Population, taking the 33 counties of Scotland ... 
291 
263 
256 
sample of the whole country. If, however, there were special causes leading 
persons belonging to one or more of the colour classes to congregate in certain areas 
to the exclusion of others, the groups in the densely populated areas would tend 
to diverge from the form of distribution found to hold for the whole country. The 
densely populated counties of Forfar, Fife, Stirling, Dumbarton and Lanark 
(excluding Glasgow), are fair samples of the boy population, and therefore in these 
densely populated areas no special causes are likely to be found to exist tending to 
change the distribution of hair colour. The same can be said of the girl populations 
of Forfar, Stirling and Dumbarton. But the still denser centres, namely the great 
cities, are different, excepting Edinburgh, which is quite like the general popula- 
tion, for both boys and girls. The cities of Aberdeen, Dundee and particularly 
Glasgow, densely populated centres, diverge largely from the general population, 
for some reason or other. What special cause or causes are in operation which 
make the chief cities, excepting Edinburgh, unrepresentative ? Two suggest them- 
selves. (1) One would expect great seaports to differ if foreigners and others 
(Irish, etc.) of non-Scottish origin, who on an average differed in their colour 
characters from the general Scottish distribution, settled in these places. 
(2) Another special cause would clearly exist in the case where a country popula- 
tion contiguous to a large town differed largely from the general population, their 
influx thereby changing the character of the town population — a population which 
otherwise should be a fair representation of the whole country. It will be seen in 
a later section that the facts support the foregoing projDOsitions at least in the 
special case of Greater Glasgow, which contains within its bounds one-fifth of the 
whole population of Scotland. 
(7) Divergency in hair colour in district groups will now be briefly considered. 
It has just been stated that of the great cities Glasgow stands out as by far the 
most divergent, Aberdeen, Dundee and Leith following, while Edinburgh is quite 
passably a sample of the general population and is thus for hair colour a repre- 
sentative sample of all parts of Scotland. Kirkcaldy, Perth, Inverness, Ayr, 
Kilmarnock, Montrose, Stirling, and otiier smaller towns moderately resemble the 
general population. Examining now the country districts, it is seen that by far 
the most divergent area is along the seaboard of the west (see Maps XLVII. and 
XLVIII.). This area contributes largely to the divergency of the north-west by 
its blackness, darkness and fairness, as revealed by the division and county analyses, 
and has the following boundaries. It commences in the north-west of Ross, is 
Biometrika vi 22 
