lis ME. E. B. BAILEY OX THE STErCTUEE OF [vol. Ixxviii, 



I Studied in 1920 seem to establish the identity of the Killie- 

 crankie Group with the tlag group strongly developed in Northern 

 Jura and Searba (1917. p. lo2) within the limits of the Islay 

 Quartzite. 



On the southern side of the pebbly Cjuartzite. interbedded 

 quartzite and black slate-hornfels continue for some distance, until 

 towards Loch Etive they give place to black slate. This Intter. 

 scarcely indurated at all, is seen at the bridge at Inveresragan, and 

 in baked condition in the Blarcreen Bm*n. Between the Blarcreen 

 Burn and Bona we Ferry there are many roadside exposures of 

 homfelsed black slate with a considerable proportion of Cj^uartzose 

 stripes. I fii'st saw the Inveresragan exposures of black slate in 

 1911 exactly where I hoped to find them from my knowledge of 

 the Dalmally sections (to be described presently). In 1919 I was 

 able to return to the subject, and was rewarded by the discovery of 

 the pebbly cpiartzite. I have no doubt, on the score of character 

 and position, that this pebbly-quartzite and black-slate assemblage 

 represents the eastward continuation of some part of the Islay 

 Quartzite, Transition Gi-roup, and Easdale Slates, as represented in 

 the Loch-Creran and Oban districts. 



Loch-Awe Xappe. — InEilean Duii'innis, immediately north of 

 Bona we Ferrv, banded calcareous homfels occurs at the edsre of the 

 Etive Granite. On the other side of the ferry, continuing for a dis- 

 tance of 6 miles, similar calcareous hornfels constitutes the strip of 

 country between the Pass-of-Brander Fault and the Etive Granite. 

 The calcareous laminae are mainly represented by malacolite, 

 colourless garnet, epidote, and tremolite. An excellent peti-o- 

 graphical account has been given by Su* Jethro Teall (190S h, 

 p. 11:1). Xear the eastern lunit of the outcrop, metamorphosed 

 limestone is more than usually prominent. 



I have examined this Pass-of-Brander outcrop several times, and 

 heartily concur with H. Kynaston's reference of it to the Ardri- 

 shaig Phyllites. The reasons for placing the Ardrishaig Phyllites 

 as a whole in the Loch-Awe, rather than in the Iltay Xappe, will 

 be discussed later I'p. 121). 



Ballappel Foundation and Iltay Xappe, north-east 

 of the Loch-Awe Xappe. — "When ]Mr. Macgregor and I 

 described the geology of the Glen-Orchy Anticline before this 

 Societv, we'ti-aced a thick stiTictiu-al succession above the Ben- 

 rdlaidh outcrop of the Sub-Eilde Complex (1912 5, p. 172). At 

 that time we did not speak of the Ballachulish Slide as a thrust, 

 and accordingly did not use the term nappe: otherwise, the 

 ensuing sequence is little more than a repetition of our published 

 conclusions : — 



Black pelitic sckist. 

 Pebbly quartzite. 



Interbedded grey pelitic scliists and pebbly 

 quartzite. 



