•±3-1 MR. E. M. AXDERSOX OX THE GEOLOGY OF [vol. lxxix, 



these, dips under a Grey Schist and Limestone belt which is a 

 continuation of that which borders the Dalradian projection farther 

 north. The ascending order is : — Struan Flags : Quartzite : Grey 

 Schist and Limestone : Banded Series : Boulder Bed : Banded 

 Series : Grey Schist and Limestone : Banded Series: Boulder Bed: 

 Schichallion Quartzite-belt (see horizontal section, PL XXV). The 

 second belt of Grey Schist and Limestone marks, as I take it, 

 the crest of the subsidiaiy anticline. The Flags must also dip 

 under the Dalradian Series near the foot of Loch Bannoch, 

 although the line between them is here difficult to define. Quite 

 apart from any evidence outside this district, 1 this seems the 

 most likely general order, though it must be emphasized that in 

 this particular connexion we are considering only the structural 

 secjuence, as regarded on a large scale. If my conclusion holds, 

 then the Dalradian Series as a whole overlies the Struan Flags 

 along this part of their border. 



Where the Grey Schist is marginal to the Flags, as it is for 

 many miles, it must be concluded that it is structurally the lowest 

 Dalradian member. As there is some ground for thinking that it 

 is also the oldest, it may follow that the Dalradian Sj T stem, although 

 intensely folded, has not here been subject to any very broad or 

 general inversion. 



This statement is not meant to be applied without reservation to 

 the area south-west of Schichallion, and it may or may not apply 

 to most of the western border of the ' projection ', where the Grey 

 Schist, as will be noted later, no longer forms the margin. It 

 certainly does not hold near Loch Tay, where the Loch Tay Lime- 

 stone dips under the Ben Lui Schist and Ben Lawers Schist, and 

 where, if my premises are correct, there must be inversion. 



The Allt Mor Limeston e. — The structure of the ground 

 immediately south-west of Schichallion has already been briefly 

 described ; but one point remains to be noted. On the Tempar 

 Burn, about 2 miles south-east of Kinloch Bannoch, a little island 

 of limestone, accompanied by graphitic schist, appears within the 

 borders of the Schichallion Quartzite-belt. A similar limestone 

 (with a remnant of graphitic schist) forms a fairly broad strip 

 in the valley of the Allt Mor, where it intervenes between the south- 

 eastern belt of Schichallion Quartzite and the north-eastern belt 

 of Killiekrankie Schist. The three formations border each other 

 rather abruptly ; but the Killiekrankie Schist is transgressed by 

 the limestone, when it is followed eastwards, and the latter curves 

 round the end of the eastern spur of Schichallion almost in contact 

 with the mountain-forming Quartzite. A tongue of limestone 

 shoots westwards along the northern slope, with Quartzite above 

 and below ; but the main mass continues east-north-eastwards, 



1 See E. B. Bailey & M. McGregor, ' The Glenorchy Anticline (Argyllshire) ' 

 Q. J. G. S. vol. lxviii (1912) pp. 164-78. The ' Eilde Flags ' of that paper are 

 probably the Struan Flag Series, and the ' unclassified schists ' are part of 

 the Perthshire Dalradian. 



