307 
with Dary's theory of the mechanics of intrusion. They are 
also in accordance with the experience gained in other regions 
of similar geological structure, as for instance large districts of 
eastern Scandinavia. 
The main features of the Paleozoic intrusions of South 
Greenland, outside the Julianehaab area, may be summarized as 
follows: 
1. The Paleozoic Plutonic rocks of South Greenland are 
granites, syenites, nepheline-syenites, and gabbros (incl. es- 
sexites). 
2. They have invaded the upper part of the earth crust at 
a time much later than that of the latest foldings of the coun- 
try. At the time of the intrusion the country was probably a 
plateau; but this, during later periods, was deeply dissected by 
the agents of denudation. The encasing rocks now remaining 
are entirely crystalline (Algonkian and Archean granites, gneisses 
and schists). 
3. The intrusions have nowhere a laccolitic habit. 
4. The heavy gabbroid rocks occur in innumerable vertical 
dykes, which are very coarse-grained and often more than 150 
meters wide. Some few boss-like masses are also found, but 
their horizontal dimensions are small, and seldom exceed one 
or two kilometers. The original form of the boss-like occur- 
rences has very often been obscured by later intrusions of more 
acid magmas. 
5. The granites and the syenites occur as large batholites 
of more or less irregular shape. These batholites are indicated 
on the map, (Pl. I). Their minimum horizontal dimension amounts 
to 5—30 kilometers or more. Both granite and syenite are of- 
ten found within one batholite. Nepheline-syenite has only been 
met with at one place outside the Julianehaab area, viz. east of 
Ivigtut. This occurrence is a small and elongated batholite, 9 
kilometers long by 2 kilometers broad. 
The junctions of the batholites with their encasing rocks 
20° 
