160 Pigmentation Survey of School Children in Scotland 
excess of this class. It is seen from the county analysis that Argyll and Arran 
account for the excess in the West Midland division and % ), Dumbarton also 
contributing in the case of the girl population. Taking the more local view 
revealed by the district analysis, it is found that the excess in Argyll thins off 
through Inverness to Ross, where it disappears. It extends eastwards and north- 
wards through Mid Perthshire and over to Deeside and the Kincardine coast. 
All these are thinly populated districts. In the populous districts between Edin- 
burgh and Glasgow excess appears sporadically here and there. It runs from 
Glasgow and Greenock through Renfrew, North Ayr to Kirkcudbright and South 
Dumfries, a slight break occurring in the district inland from the town of Ayr. 
Finally, south of the Lothians, a tract from Peebles to Berwick shows moderate 
excess. Passing from the purely local distribution to the distribution in a general 
sense, it is quite clear that the light-eyed class is more characteristic of the south 
than of the north. The excess is more marked in the girl population. Renfrew, 
Selkirk and Peebles are the exceptions. These counties are slightly micrometropic, 
or, compared with the general population, the proportion of the light-eyed class is 
scarcely so great, although not significantly less. 
(7) Medium Eyes. (Maps XVII., XVIII. XXXV. and XXXVI.) Turning 
now to the mixed class of eye defined as medium, it is found that there is 32'72 
per cent, of this class for boys and 32"06 per cent, for girls in the general popu- 
lation. The only division in Scotland where this class is in significant excess is 
the populous South-Western division or Lanark group of counties. This result 
is found for both boys and girls. The North-Eastern division or Aberdeen group 
shows a moderate excess {^^ and $ ), but the excess is not greater than could 
quite possibly occur in making a random selection of the same number from the 
general population. Examining the distribution with respect to counties, it is 
seen that Lanark (excluding Glasgow), Dumfries, Selkirk and Peebles — just those 
counties deficient in all the other classes (excepting Dumfries which has also 
excess of light eyes) — are the megalometropic counties of this class. These counties 
are all contiguous and the result is common to both boys and girls. The counties 
of Fife and Aberdeen and the cities of Dundee and Aberdeen have also an excess 
of medium eyes (f^ and ?). Caithness and the Orkney Islands show a 
moderate excess of the class. Taking the local distribution, it is found that West 
Renfrew, North Lanark stretching into Stirling, Selkirk and the town of Dumfries, 
are the areas where the greatest excess is shown in these counties. West Fife 
in Fifeshire, the southern portion of the Buchan coast in Aberdeenshire, account 
for the moderate excess found in these counties. The coast from John o' Groat's 
to Banff, with one or two local exceptions, shows an excess of the medium class. 
Taking a general view of the distribution of medium eyes, it is seen that excess 
of the class is restricted to an area commencing with Fife and extending right to 
Dumfries through Lanark. The other regions of excess are more or less detached 
from this region. 
