48 
their differences and the sheeted structure as well as the thick 
platy parting gradually disappear when we approach nearer to 
the contact. Moreover, the size of grain becomes variable in 
irregular ‘schlieren’ and large numbers of pegmatitic veins of 
some decimeters in breadth appear. The size of grain of these 
pegmatites (which consist of felspar, nepheline, arfvedsonite and 
occasionally eudialyte) frequently exceeds 1 decimeter. On the 
last 5 to 10 meters nearest the contact the rock changes over 
to a very coarse-grained foyaite, variegated white and black, 
which contains fragments of augite-syenite. The largest of the 
fragments observed was 0°3><1'5 meters. The pegmatitic veins in 
this border-facies are arranged parallel with the contact-plane, 
or they go round the augite-syenite fragments. The augite- 
syenite, on the other hand, shows no structural variations in 
towards the surface of contact. It results from these observa- 
tions, that the consolidation of kakurtokite has taken place later 
than that of the augite-syenite, but while the latter still pos- 
sessed a high temperature. 
Dykes. — Only a very small number of dykes have been 
seen in Kringlerne. West of Laxefjæld two vertical dykes of 
respectively 8 and 2 meters in breadth have ben observed, with 
the directions Е. М. Е. —У. $. W. and N. E.—S. W.; they consist 
of a rock-type resembling bostonite, fine-grained and light 
greenish gray with plate-like phenocrysts of felspar. Occasion- 
ally, small tinguaitic dykes have been seen in boulders of kak- 
ortokite. 
SOUTH-EASTERN AND SOUTHERN BORDER OF 
THE COMPLEX. 
General features. — Behind the south-eastern and southern 
margins of the igneous complex, the Kangerdluarsuk amphitheatre 
is bounded by high mountains, Kidtlavat and the two Iviangusats 
(Pl. V, Figs. 2 and 3). These mountains are composed of Al- 
