376 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 
quite obliterated, and new lines of foliation or cleavage super- 
induced. The rocks are not equally metamorphosed over the 
whole area. The greatest amount of alteration occurs in the 
region near the mouth of Loch Fyne, between Sgat Mohr and 
Caisteal Aoidhe on the east side, and in the corresponding tract on 
the Kintyre coast to the south-east of Loch Tarbert. Stretching 
away to the north-east, by the heads of Loch Riddon, Loch 
Striven, and Loch Goil, is a belt in which the maximum of meta- 
morphism is shown, on each side of what is called the axis of 
the “anticline of foliation.” This anticlinal axis is that 
mentioned in the report of the Society’s excursion, on 25th June, 
1898, to Loch Long side, wherein it was stated that the strata at 
the point where it passes are more altered and twisted than those 
to the north and to the south. It is an “anticline of foliation,” 
not strictly one of bedding, but rather one “of the early folds 
that affect the bedding.” Before it was formed, the strata had 
already, by earth movements, been greatly folded, crumpled, and 
foliated. Those nearer its centre have apparently been covered 
by a greater thickness of overlying strata, and been subjected to 
a greater heat than have those farther away. Therefore, as we 
recede from the centre towards the south-east and towards the 
north-west, the rocks are less altered. Continued earth movements 
have afterwards arched up the strata along the line indicated, pro- 
ducing new curvings and foliations. Subsequent denudation has 
worn off an immense thickness of material, so that the strata 
along the line of anticline do not show at the surface as a ridge 
elevated above those on its flanks. In fact, anticlines of ancient 
date do not usually rise into ridges, but rather tend to be hollowed 
into valleys, as the weakest part of folded strata runs along this 
line, the rocks there having been strained and stretched, while at 
the bottom of a syncline they have been compressed. A good 
example of such a formation was seen at the Society’s excursion 
to Killin on 19th April, 1897, when it was pointed out that the 
valley occupied by Glen Dochart and Loch Tay had been hollowed 
out of an anticlinal arch. 
The axis of the anticline in Cowal runs parallel to the great 
boundary fault which crosses the country in a north-east and 
south-west direction, cutting off the older Highland rocks to 
the north-west from the newer Lowland rocks to the south-east. 

