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THE FRESH-WATER LOCHiS OF SCOTLAND 
the Keuper sandstones and marls and the Lower Lias. On the other 
hand, the well-known footprints obtained from the sandstones near 
Dumfries and Corncockle Moor are regarded by some investigators 
as proving the Permian age of the sediments in which they are found. 
At the base of the great succession of Mesozoic rocks in the 
Highlands we find a sequence of conglomerates, sandstones, and marls 
which have been grouped with the Trias. They occur in the north- 
east of Scotland, the western seaboard of the Highlands, and the Inner 
Hebrides. The development of these rocks near Elgin is of ex- 
ceptional importance on account of the remarkable assemblage of 
reptilian remains which they have yielded. Following the discoveries 
of Amalitzky in Northern Russia, Mr E. T. Newton and other 
authorities have suggested that these reptiliferous sandstones belong 
partly to Permian and partly to Triassic time. 
On the western seaboard of the Highlands they occur at Gruinard 
Bay, where they are thrown down by powerful faults against the 
Torridon Sandstone. They appear again at Applecross, at Ardna- 
murchan, in Raasay, and in Sleat, where they graduate upwards into 
the Lower Lias. Elsewhere, as, for example, at Inch Kenneth, Gribun, 
Loch Alvie, and Morvern, they are covered unconformably by 
Upper Cretaceous strata, or by contemporaneous volcanic rocks of 
Tertiary age. 
JURASSIC 
The Jurassic rocks of Scotland occur in areas far apart from each 
other : on the east coast of Sutherland, in the basin of the Moray 
Firth, along the Western seaboard of the Highlands, and in the Inner 
Hebrides. They are relics of deposits ranging from the Lower Lias 
to the Upper Oolite, once extensively developed in the northern part 
of the kingdom, and preserved from destruction partly by powerful 
faults and partly by a covering of contemporaneous volcanic rocks of 
Tertiary age. The largest development in the north-east of Scotland 
forms a narrow belt, about 16 miles in length, on the coast of Suther- 
land, from Golspie to near the Ord of Caithness. Patches of Jurassic 
rocks appear again at the base of the Ross-shire cliffs, to the north 
and south of the Sutors of Cromarty. In both of these areas they 
have been let down by faults against the crystalline schists and Old 
Red Sandstone. The dislocation at the base of the Ross-shire cliffs 
is a continuation of that which traverses the Great Glen and forms 
such a striking feature in the topography of the country. The 
precise age of these faults is uncertain, but they must be more recent 
than the Upper Oolite, inasmuch as these rocks have been affected 
by the movements. It is not improbable that the fracture traversing 
the Great Glen may be of much more ancient date, reaching back to 
Old Red Sandstone time, if not to an older period. 
