LIST OF ILLUSTRATIONS. 



Frontispiece. — Life in the Silurian Age 



To face Title. 



FIO. 



I. 



2. 



3- 



4- 



5. 

 6. 



7. 

 8. 



9. 



lO. 



II. 



12. 



\2a. 

 13. 



14. 



15. 

 16. 



17. 



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21. 



Bank of stream or coast, showing stratification 

 Section at Niagara Falls . 



Section obtained by boring, near Goderich, Ontario . 

 Inclined beds, holding fossil plants .... 

 Ideal section of the Apalachian Mountains . 

 Generali^ed section across England from Menai Straits 



the Valley of the Thames ..... 

 Generalised section from the Laurentian of Canada to the 



coal-field of Michigan ...... 



Unconformable superposition of Devonian Conglomerate on 



Silurian slates, at St. Abb j Head, Berwickshire 

 Section of Trenton Limestone, Montreal 

 Dia'^ram showing different state of fossilisation of a cell of a 



Tabulate Coral ....... 



Cast of erect tree {Si^llaria) in Sandstone . 

 Protichnites septem-notatus ...... 



Footprints of modern Limulus, or king-crab 



Current markings on shale, resembling a fossil-plant . 



Frontispiece. Alagnified and restored section of a portion of 



Eozoon canadense ....... 



Ideal section, showing the relations of the Laurentian and 



Huronian ........ 



Small weathered specimen of Eozoon .... 



Nature-printed specimen of Eozoon slightly etched with acid 

 Magnified group of canals in supplemental skeleton of Eo- 

 zoon .......... 



Portion of Eozoon magnified 1<X) diameters 



Magnified portion of shell of Calcarina . . . . 



Amaba, a fresh- water naked Rhizopod ; and Actinophrys, 



a fresh-water Protozoon ....... 



Nonionina^ a modem marine Foraminifcr . . . . 



I'A(i 



4 



4 



5 

 6 



7 



10 

 13 



IS 

 16 



17 



iS 



18 



20 



24 

 28 

 29 



31 



3f 



32 



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