XXVI CONTENTS. 



CHAPTER XX VI. 



On the stratified rocks usually called ' primary' Proofs from the dispo- 

 sition of their strata that they were originally deposited from water Alter- 

 nation of beds varying in composition and colour Passage of gneiss into 

 granite Alteration of sedimentary strata by trappean and granitic dikes 

 Inference as to the origin of the strata called 'primary' Conversion of argil- 

 laceous into hornblende schist The term 'Hypogene' proposed as a substitute 

 for primary l Metamorphic ' for ( stratified primary ' rocks No regular order 

 of succession of hypogene formations Passage from the metamorphic to 

 the sedimentary strata Cause of the high relative antiquity of the visible 

 hypogene formations That antiquity consistent with the hypothesis that 

 they have been produced at each successive period in equal quantities Great 

 volume of hypogene rocks supposed to have been formed since the Eocene 

 period Concluding remarks . . . . . 365 



Table I. Showing the relations of the various classes of rocks, the Alluvial, 



the Aqueous^ the Volcanic, and the Ilypogene, of different periods 386 



Table II. Showing the order of superposition of the principal European 



groups of sedimentary strata mentioned in this work . . 389 



Notes in explanation of the Tables of fossil shells in Appendix I. . 393 



Appendix I. Tables of fossil shells by Monsieur G. P. Deshayes . 1 



Appendix II. Lists of fossil Shells chiefly collected by the author in Sicily 



and Italy, named by M. Deshayes . . .53 



Glossary, containing an explanation of geological and other scientific terms 



used in this work . . . . .61 



Index . . . .85 



