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simultaneously with, partly later than the felspar. The quantity 
of eudialyte is extremely variable; at a few places the whole 
rock appears red from this mineral, but often we can walk 20 
and even 50 meters over naked surface of sodalite-foyaite with- 
out seeing a single eudialyte crystal. Ainigmatite, ægirine and 
arfvedsonite are constant components, and the arfvedsonite is 
as usual the last mineral to crystallise; sometimes a little rinkite 
can be seen macroscopically. 
Like the naujaite the sodalite-foyaite has a well-marked 
system of almost horizontal partings, which divide it into thick 
beds; the partings in both rocks are parallel to one another 
and also to the direction of the transitional zone between the 
rocks. A banded structure has been observed in a foyaite hill, 
two or three kilometers north-east of Nunasarnausak; at this 
place the foyaite contains numerous, almost horizontal, very 
coarse-grained bands which are richer in arfvedsonite than the 
bulk of the rock. 
Transition from naujaite to sodalite-foyaite. — There is 
no distinct contact between the sodalite-foyaite and the under- 
lying naujaite, the two are connected by a gradual transition. 
The transitional zone has as a rule a thickness of some meters. 
On ascending we can observe how the felspar plates in the 
uppermost beds of the naujaite gradually become smaller and 
the poikilitic sodalite crystals fewer and fewer; at the same 
time a later generation of sodalite appears as interstitial an- 
hedra between the other constituents. 
Shape of the sodalite-foyaite body. — A little to the west 
of Tupersuatsiak the transitional zone between the naujaite and 
sodalite-foyaite lies 90 meters above the sea, and from this spot 
it rises towards the west, south and east. One and a half kilo- 
meters further west, at Naujakasik, it lies at a height of about 
200 meters, and at S. Siorarsuit about 400 meters above the 
sea. Towards the south-west and south the transitional zone 
rises almost as rapidly as the mountain surface itself, and as 
Ex 
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