small amount of black minerals, and outwardly the white zone 
passes into the more uniform soda-granite. The size of grain 
of the latter is sometimes variable, so that coarse grained por- 
tions may alternate with fine-grained in the most irregular manner, 
even within one and the same hand-specimen. At some places 
the soda-granite contains small patches of a conspicuous, blue, 
felt-like mineral, probably crocydolite, which seems to have 
originated by alteration of the hornblende. As a rule the junc- 
tion between the soda-granite and the surrounding augite-syenite 
presents a sharp line;' the augite-syenite retains its normal 
character right in to the contact, while the soda-granite shows 
irregular variations in the size of grain. 
It follows from the manner in which this soda-granite is 
connected with the sandstone fragments, that it must have 
originated by the magma of the augite-syenite dissolving the 
sandstone, so that the soda-granite in this locality may be 
characterised as a resorption-facies of the augite-syenite. Since 
the conditions mentioned above show, that the soda-granite has 
solidified later than the surrounding augite-syenite, we must 
conclude that the absorption of silica has lowered the temper- 
ature of consolidation of the magma. 
IVIANGUSAT AND KITDLAVAT. 
The Algonkian granite of these mountains, which form the 
southern and south-eastern enclosure of the newer igneous 
complex, is a coarse-grained, white or reddish, biotite granite 
with a strong tendency to porphyritic structure. The size of 
оташ remains unchanged right on to the junction with the 
newer abyssal rocks, but in the proximity of the latter the habit 
of the granite often differs from the ordinary; thus at the junc- 
tion north-east of Laxefjeld the granite was found to be rich 
in a mineral resembling crocydolite, which apparently replaced 
the original, dark-coloured components. In comparison with 
