EXPLANATION OF PLATE 1. 11 



f. 8. Basal tiform products of Modern Volcanos. 



g. Trachyte forming Dykes. 



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



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

 Cones. (Auvergne.) 



i. — i. 5. Lava, Scoriae, and Craters of active Volcanos. 

 (i. 1. — i. 4. Etna. i. — 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. — 1. 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 formations represented in our 

 Section. Their usual Order of Succession and Names are 

 expressed in their respective places, and detailed descrip- 

 tions of their several characters may be found in all good 

 Treatises on Geology. 



The leading Groups of these Formations are united by 

 colours, marking their separation from the adjacent groups ; 

 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 re- 

 spectively distributed. 



Although the deposits of Peat Bogs, and Calcareous Tufa 

 are of too local a nature to be generally included in the 

 series of stratified Rocks, they are represented in this Sec- 

 tion (Figs. 31, 32), because they sometimes operate locally 

 to a considerable extent in adding permanent and solid 

 matter to the surface of the Globe. 



