132 The Scottish Naturalist. 



3. The Durness-Eriboll Limestone is the newest sedimentary 

 rock 1 in the district. 



4. The Upper Quartzite and Upper Limestone of Murchison are 

 non-existent ;'- the so-called Upper Quartzite is the lower Quartzite 

 repeated, and the so called Upper Limestone is in reality a re- 

 petition of a part of the Durness Limestone itself. 



(b) THE STRATIGRAPHY. 



5. There is no :i conformable upward succession, as held by 

 Murchison and his followers, from the Silurian Rocks into the 

 Eastern Gneissic series. 



6. In some spots the basement beds of the local Palaeozoic rocks 

 rest unconformably 4 upon one member of the Eastern metamorphic 

 series, while 



7. Generally speaking, the line of junction of the unaltered 

 Palaeozoic rocks and the Eastern Metamorphic series is a great 

 fault 5 and overthrust, along which 



8. The Eastern Metamorphic series has been forced over the 

 Silurian rocks by Earth-movements which have acted since Lower 

 Silurian (Ordovician) times. 



9. The schists and gneisses of Sango Bay and Farrid Head, 

 which repose locally upon the Durness Limestones, do not form 

 part of a continuous sedimentary succession. They are a part of 

 the Easter or Upper Gneissic series, and they are separated from 

 the Durness Limestone by planes of fault. 7 



to. As these Schists, &c, of Sango Bay are similar in character 

 and arrangement to the zones of pressure — schists occurring above 

 the great overthrust in Eriboll, 8 nearly ten miles to the S.E. they 

 afford a rough index of the enormous distance to which the meta- 



1 Nicol, Q./.G.S., 1861, p. 88, &c. ; Callaway, Q.J.G.S., 1SS1, p. 244, 

 Lapworth, Geol. Mag. 1883, p. 127. 



2 Nicol, Q.J.G.S., 1861, p. 91, &c, Hudleston, Geol. Mag., 1882, p. 394, 

 Lapworth, Geol. Mag., 1883, r>. 127, Callaway, Q.J.G.S., 1883 p. 367. 



3 Nicol, Q.J.G.S., i86i,V86, Hicks, QJ-G.S., 1883, p. 137, Callaway, 

 Q./.G.S., 1883, p. 357, Lapworth, Geol. Mag., 1883, P- I2 7- 



4 Lapworth, Geol. Mag., 18S3, p. 127, Callaway, Q.J.G.S., 1883 p. 407, 

 compare Hicks, Geol. Mag. 1880, p. 21. 



5 Nicol, Q.J.G.S., 1861, p. 86, Callaway, Q.J.G.S., 18S3, p. 357, &c, 

 Hicks, Q.J.G.S., 1883, P- 157, Lapworth, Q.J.G.S., 1883, p. 421. 



6 Callaway, Q.J, G.S., 1883, p. 410, Lapworth, I.e. ; compare Nicol, Q./. G.S., 

 1861, p. no, and Hicks Geol. Mag., 1880, p. 17. 



i Nicol, Q.J.G.S., 1861, p. 87-88, Callaway, I.e. 1S83, p. 241, Lapworth, 

 see Appendix. 



s Lapworth, T884, see Appendix, p, 104. 



