(217 ) 
IX. —On the Geology of the Ferée Islands. 
F.R.S. L. & E. (Plates XIII, XIV., XV., XVI) 
(Read March 15, 1880.) 
By James Gerke, LL.D., 
CONTENTS. 
, PAGE 
I. IntTRopucTION 218 3. Miocene Age of the Strata: 
Physical Conditions, ete. 
II, Paysican FEATURES OF THE 4, Position of old Volcanic Centre 
IsLANDS. 
1. Extent, Form, and Trend of = aaa aga Ae 
the Islands and Fiords 220 Stns 
2. Configuration and Height of 1. Early Notices of Glacial Phe- 
the Land 221 nomena 5 ; 
3. Valleys 222 2. Glaciation 
4, Lakes and Streams 222 3. Till or Boulder-clay 
4, Erratics and Morainic Débris . 
III. Grotocican STRUCTURE OF THE 5. Lake-Basins 
ISLANDS. 
i Genel Din or the Strata 993 VI. OricIN oF THE V ALLEYS AND Fiorps: 
2. Contemporaneous or Bedded SUBAERIAL AND GLactaL ERo- 
Basalt-rocks of Suderée 223 Suen 
3. Bedded Tuffs of Suderée 226 1. Forms of Valleys 
4, Coal and Coal-bearing Beds of 2. Fiords ; 
Suderde 227 3. Trend of Valleys ead Biords 
5. Coal, &c. of Asean ead Main Water-parting 
Tindholm ‘ 229 4, Origin of Main Water-parting 
6. Subsequent or Intrusive Basalts 5. ioangesieete Erosion : 
of Suderée . 230 6. Former Greater Rainfall 
7. Contemporaneous or Bedded 7. Glacial Erosion of Valleys 
Basalt-rocks of Northern 8. Weathering of Glaciated Sur- 
Islands ; 231 face : 
8. Bedded Tuffs of N Mtoe 9, Limited Necaraelelizoh of Till 
Islands 235 on Land c 
9. Subsequent or meaetve Tei 10. Direction of Jce-flow and 
of Northern Islands. 235 Extent of Ice-sheet . 
11. Origin of Erratics and Morainic 
IV. THicknEss OF THE STRATA: Con- Débris 
DITIONS UNDER WHICH THEY 
WERE AMASSED. VII. Marine Eroston 
1. Thickness of the Strata 237 VIIL Peat anp Buriep TREES 
2. Igneous Rocks of Subaerial 
Origin : . 237 TX. Expanation oF Puates 
VOL. XXX, PART I. 
Dawe 
PAGE 
240 
242 
243 
244 
249 
250 
251 
