EXPLANATION OF PLATE I. 11 



f. 8. Basaltiform products of Modern Volcanoes. 



g. Trachyte forming Dikes. 



g. 1. Trachyte forming overlying Domes. (PuydeDome.) 



h. 1. h. 2. Lava of extinct Volcanoes, forming undisturbed 

 Cones. (Auvergne.) 



i. — i. 5. Lava, Scoria?, and Craters of active Volcanoes, 

 (i. 1.— i. 4. Etna. 1.— 5. Stromboli.) 



k. — k. 24. Metalliferous Veins. 



k. 15'. Lateral expansions of Veins into metalliferous 

 cavities, called by the Miners Pipe Veins, or Flats. 



1. — I. 7. Faults, or fractures and dislocations of the strata. 

 The continuity of stratified Rocks is always inter- 

 rupted, and their level more or less changed on the 

 opposite sides of a fault. 



It is unnecessary here to give detailed descriptions of the 

 28 divisions of the Stratified Rocks represented in our Sec- 

 tion. Their usual Order of Succession and Names are ex- 

 pressed in their respective places, and detailed descriptions 

 of their several characters may be found in all good Trea- 

 tises on Geology. 



The leading Groups of Formations are united by colours, 

 marking their separation from the adjacent groups y and the 

 same colours are repeated, in the headings above the figures 

 of Plants and Animals that characterize the several series 

 of Formations, to show the extent of the strata over which 

 the Organic Remains of each Group are respectively dis- 

 tributed. 



The Formation of Peat Bogs and Calcareous Tufa are 

 of too local a nature to be included in the series of stratified 

 Rocks represented in this Section ; although they sometimes 

 operate locally to a considerable extent, in adding perma- 

 nent and solid matter to the surface of the Globe. 



