INDEX. 



101 



Pen tali ca, great limestone of the Val di 

 Noto seen in the valley of, 64 



Pentland, Mr., on the bones of animals 

 from Australian caves, 144 



on the mammiferous remains of 



the Upper Val d'Arno, 220 



Peperino, traversed by dikes near Pala- 

 gonia see diagrams, Nos. 6 and 7, 69 



. dikes of, how formed, 70 



sections of calcareous grit and see 



diagrams Nos. 9 and 10, 72 



Peperinos, of the Val di Noto, 71 



how formed, 71 



Perpignan, the country between Olot and, 

 occasionally shaken by earthquakes, 191 



.- fossil shells of see Tables, Appen- 

 dix I. 



Peru, proofs of successive elevation of the 

 coast of, 130 



Pewsey, Vale of, 308 ' 



Phillips, Mr., his analysis of chalk flints, 

 238 



Philosopher's Tower on Etna, 128 



Phlegraean Fields, minor cones of the, 125 



Piana, conglomerate of, 211 



Piazza, dip of the tertiary strata at, 74 



Piedmont, tertiary strata of, 20, 21 1 



their relative age see diagram, 



No. 4, 21 



Pitchstone, a thin band of, formed at the 

 contact of the dikes of Somma and 

 intersected beds, 124 



Placentia, character of the sediment 

 transported by rivers in the territory of, 

 161 



Plants, their fossilization partial, 31 



fossil, importance of, in geology, 47 



Plas Newydd, changes caused in sedi- 

 mentary strata by a volcanic dike near, 

 368 



Plastic clay and sand of the London basin, 

 278 



its thickness, composition, &c., 278 



organic remains rare in the, 279 



clay and sand of the Paris basin, 



244 



alternates with calcaire grossier, 244 



Pliny does not mention the Auvergne vol- 



canos in his Ifatural History, 269 

 Pliocene period, newer, derivation of the 



term, 53 

 proportion of living species in the 



fossil shells of the, 53 



marine formations of the, 62 



___ contortions in strata of the, in the 



Isle of Cyclops see wood-cut, No. 



15,80 



strata of the, invaded by lava see 



wood-cut No. 16, 81 

 subterranean rocks of fusion, formed 



during the, 107 

 . fresh-water formations of the, 137 



Pliocene period, newer, osseous breccias 



and cave deposits of the, 139 



alluviums of the, 145 



extinct animals in breccias of the, 



140 

 Pliocene period, older, proportion of living 



species in the fossil shells of the, 54 

 position of the beds referrible to this 



era see diagrams No?. 3 and 4, 20, 21 



mammiferous remains of the, 59 



tertiary formations referrible to the, 



155 



volcanic rocks of the, 183 



elevation of land on the East coast 



of England since the commencement of 



the, 316 

 Pliocene period, fossil shells of the see 



Table, Appendix 1. 

 general results derived from the 



fossil shells of the Appendix J., p. 47 

 number of species of fossil shells 



common to different formations of the 



Appendix I., p. 47 

 number of living species in the fossil 



shells of the Appendix I., p. 47 

 number of species common to the 



Miocene and Appendix I., p. 49 



geographical distribution of the 



living species of the Appendix I., 

 p. 51 



strata of Sicily, their dip and di- 

 rection, 73 



Pliocene strata of Sicily, origin of the, 103 



. changes of the surface during and 

 since their emergence, 109 



strata, newer, only visible in coun- 

 tries of earthquakes, 129 



Plomb du Cantal, successive accumulation 



of the, 240 



i a^e of the volcanic rocks of the, 

 260, 262 



its height, form, structure, &c., 263 



fresh-water limestone covered by 



volcanic rocks on the northern side of 

 the, 263 



Plutonic rocks, 353 



distinction between volcanic and, 



359 



their relative age, 364, 377 



changes produced by, 370 



why those now visible are for the 



most part very ancient, 379 

 Podolia, tertiary formations of, 215 

 Poggibonsi, conglomerate of, 160 

 Pont du Chateau, alternation of volcanic 



tuff and fresh-water limestone at, 258 

 Portella di Calanna, furrows in the defile 



called, how formed, 147 

 Pratt, Mr., on the mammiferous remains of 



the Isle of Wight, 281 

 Pressure, effects of, on the consolidation 



of strata, 334 



