CONTENTS 



PART I. 



Page 



List of Illustrations xxi 



Description of Map xxvii 



Notice of the ancient Topography of the Silurian Region xxxi 



CHAPTER I. 



INTRODUCTION. 



Design of the work. — Previous state of geological knowledge. — Order of the older fossiliferous strata. — 

 Interval to be filled up, between the secondary deposits previously described, and the older slaty 

 rocks. — Origin of this inquiry, and method pursued in following it out. — General view of the oldest 



fossiliferous deposits . . 3 



CHAPTER II. 



OOLITIC SYSTEM. 



Inferior Oolite.— Lias.— Outliers of Lias (PI. 29. figs. 1, 2, 3.) 13 



CHAPTER III. 



NEW RED SYSTEM. 

 UPPER FORMATIONS. 



1. Saliferous Marls, Keuper, &c. — 2. Red Sandstone and Quartzose Conglomerate (PI. 29. figs. 1 — 4.). . 27 



CHAPTER IV. 



NEW RED SYSTEM. 

 LOWER FORMATIONS. 



3. Calcareous Conglomerate. — 4. Lower New Red Sandstone (PI. 29. figs. 5. et seq.) 46 



CHAPTER V. 



TRAP ROCKS. 

 (General view of.) 



Trap Rocks compared with Volcanic Products, and shown to be of igneous origin. — Distinctions between 



contemporaneous and intrusive Trap Rocks 68 



CHAPTER VI. 



CARBONIFEROUS SYSTEM. 

 Introduction. — Upper Coal Measures and Freshwater Limestone in Shropshire. (PI. 29. figs. 5 — 9.) 79 



