156 Pigmentation Survey of School Children in Scotland 
(e) Jet Black Hair. (Maps XI., XII., XXIX. and XXX.) In a general way, 
the distribution of jet black hair resembles that of dai k hair. While this however 
is the case, the jet black class seems to be more scattered than the dark-haired 
class. Taking the divisions first, the Northern, North- Western and West-Midland 
divisions are clearly megalometropic both for boys and girls. The North-Eastern, 
South-Eastern and Southern ((/), the South-Eastern and South-Western ($), are 
micrometropic; the remaining divisions are fair samples of the general population — 
they are mesometropic. Surveying the counties, it is seen that the excess in the 
Northern division is due to Caithness ; the excess of the North- Western division 
is equally divided among the respective counties, while the exce.ss of the West- 
Midland division is due to Argyll and Bute and slightly to Dumbarton. In the 
South-Western division, although itself meso- ($) or micrometropic (</), the 
county of Renfrew stands alone in showing significant excess of this class. The 
East-Midland and North-Eastern divisions are not at all uniform in their distri- 
bution of jet black hair. Thus ((/ and $) Perth resembles the contiguous county 
of Argyll in showing excess; only the eastern portion ((/) is micrometropic. 
Among girls, Fife is the only eastern county in this division which is micro- 
rnetropic. The other eastern covuities and Dundee show a slight excess over the 
general population. Aberdeenshire (but not Aberdeen city) stands out as mega- 
lometropic, although the North-Eastern division itself is either meso- (?) or 
micrometropic (cf). Taking now a more detailed view of the distribution locally, 
one notes that, starting from John o' Groat's, excess of jet black hair runs along 
the coast to Inverness, where it leaves the coast and permeates the upper regions 
of the Findhorn, Spey and Donside. A slight excess is found along the Buchan 
coast. It is absent again until the Forfar and Fife coasts are reached, when 
again slight excess is noticed. It is in defect south of the Forth on the coast- 
line. Running inwards from Fife and Forfar the excess increases and reaches 
a maximum in North Perthshire, where it unites with the excess in the Spey 
valley and the slight excess of Donside. Southwards from Perthshire it reaches 
Stirling, Dumbarton, and a portion of Renfrew. Northwards it runs through 
Inverness, part of Ross, and on to Skye and Lewis. It avoids the main portion 
of Argyll where there is great excess of dark hair, but affects the portion con- 
tiguous to Skye and Inverness, i.e. the mainland to Ardnamurchan Point, and the 
Isles of Mull, Tyree, Coll and Rum. An isolated spot occurs in Wigtown ( $ ), and 
in North Ayr and the contiguous portion of Lanark (</). A general view of this 
class, small numerically, shows that jet black hair, like dark hair, is characteristic 
of Highland counties, hut that the distribution is not so restricted as in the case of 
dark. TJiere is a greater scatter in the distribution for boys than in the corre- 
sponding distribution for the girl jwpidation. 
