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close south-west of Narsak. Their ground-mass is fine-grained 
and of a gray colour; it is speckled with moderately small 
phenocrysts of a reddish-white felspar with broad rectangular 
outlines. One of these dykes is five meters wide and runs in 
the direction north-south, the other, two or three meters wide, 
running in the direction north-east to south-west. 
(2) A dyke 17 centimeters wide of a light-coloured, fine- 
grained arfvedsonite-granite was found in 1888 by Dr. Sreensrrur 
on the north side of the harbour at Narsak. This dyke is re- 
markable for its coarse-grained border-zones. 
(3) Gray, fine-grained, bostonite-like dykes of about half a 
meter in width and irregular sinuous course occur at several 
places in the neighbourhood of the harbour. 
(4) Perhaps the commonest of all the dykes are composed 
of a peculiar, jasper-like rock of bluish-black or greenish-black 
colour. These dykes are only 0'1 meter in width. Their 
border zones are of a glassy or pitchstone-like appearance and 
contain spherulites of a few millimeters in diameter with a 
fluxional arrangement. The central zone of the dykes consists 
almost entirely of spherulites, which may reach one centimeter 
in diameter, and here also some few small phenocrysts occur 
of a transparent felspar, without twinning. Under the micro- 
scope the spherulites appear turbid and brown or brownish- 
green; they consist of radiating, extremely fine fibres. They 
seem to have originated through devitrification after the rock 
had solidified. These dykes cut those mentioned under (1). 
THE NORDMARKITE 
AND THE ROCKS OF KAKARSUAK. 
The nordmarkite. — This rock occupies the north-eastern 
part of the plain around Narsak and composes the slope of 
Mount Kakarsuak which faces Narsak. Towards the north- 
west the nordmarkite extends across Panernak Bay to Nungmiut 
where it bends round towards the north-east along the south 
