Contents xiii 



up valley ; Las Amolanas, silicified wood — conglomerates, nature 

 of former land, fossils, thickness of strata, great subsidence — 

 Valley of Despoblado, tufaceous fossils, deposit, complicated 

 dislocations of — Kelations between ancient orifices of eruption 

 and subsequent axes of injection — Iquique, Peru, fossils of, salt- 

 deposits — Metalliferous veins— Summary on the Porphyritic 

 conglomerate and Gypseous formations — Great subsidence with 

 partial elevations during the Cretaceo -oolitic period — On the 

 elevation and structure of the Cordillera — Recapitulation on the 

 tertiary series — Relations between movements of subsidence and 

 volcanic action — Pampean formation — Recent elevatory move- 

 ments — Long-continued volcanic action in the Cordillera. Con- 

 clusion . . . PAGE 535 



APPENDIX TO PART II. 



Descriptions of Tertiary Fossil Shells from South America, 



by G. B. Sowerby, Esq., F.L.S., &c 605 



Descriptions of Secondary Fossil Shells from South America, 



by Professor E. Forbes, F.R.S., &c 624 



INDEX 629 



