X 



CONTENTS. 



CHAPTER XIX. 



NEW RED SANDSTONE GROUP. 



Distinction between New and Old Red sandstone — Between Upper and Lower 

 New Red — Muschelkalk in Germany (p. 237.) — Fossil plants and shells of 

 New Red Group, entirely different from Lias and Magnesian limestone — 

 Lower New Red and Magnesian limestone (p. 239 ) — Zechstein in Germany 

 of the same age — General resemblance between the organic remains of the 

 Magnesian limestone and Carboniferous strata — Origin of red sand-stone and 

 red marl (p. 242.) 



CHAPTER XX. 



THE COAL, OR CARBONIFEROUS GROUP. 



Carboniferous strata in the south-west of England — Superposition of Coal- 

 measures to Mountain limestone — Departui-e from this type in north of 

 England and Scotland — Freshwater strata (p. 244.) — Intermixture of fresh- 

 water and marine beds — Sauroidal fish — Fossil plants (p. 247.) — Ferns and 

 Sigillariae — Lepidodendra — Calamites (p. 250.) — Coniferae — Stigmarise. 



CHAPTER XXI. 

 CARBONIFEROUS GROUP Continued, and old red sandstone. 

 Corals and shells of the Mountain limestone — Hot climate of the Carboniferous 

 period inferred from the marine fossils of the Mountain limestone and the' 

 plants of the Coal (p. 254.) — Origin of the Coal-strata — Contemporaneous 

 freshwater and marine deposits — Modern analogy of strata now in progress in 

 and around New Zealand — Vertical and oblique position of fossil trees in the 

 Coal (p. 257.) — How enveloped — How far they prove a rapid rate of depo- 

 sition — Old Red sandstone (p. 262.) — its subdivisions — its fossil shells and 

 fish. 



CHAPTER XXn. 



PRIMARY FOSSILIFEROUS STRATA. 



Primary Fossiliferous or Transition Strata — Term "Grauwacke" — Silurian 

 Group — Upper Silurian and Fossils (p. 265.) — Lower Silurian and Fossils — 

 Trilobites (p. 267.) — Graptolites — Orthocerata — Occasional horizontahty of 

 Silurian Strata— -Cambrian Group (p. 270.) — Endosiphonite. 



CHAPTER XXm. 



ON THE different AGES OF THeTvOLCANIC ROCKS. 



Tests of relative age of volcanic rocks — Test by superposition and intrusion — 

 By alteration of rocks in contact — Test by organic remains (p. 273.) — Test 

 of age by mineral character — Test by included fragments — Volcanic rocks 

 of the Recent and Newer Pliocene periods (p. 275.) — Miocene — Eocene — 

 Cretaceous — Oolitic (p. 278.) — New Red sandstone period — Carboniferous 

 — Old Red sandstone period — Silurian — Upper and Lower Cambrian peri- 

 ods (p. 280.) — Relative ages of intrusive traps. 



