XV] CONTENTS. 



Chapter XXXVII. — On the different Ages of the Metamorphic Rocks. 



Age of each set of metamorphic strata twofold — Test of age by fossils and min- 

 eral character not available — Test by superposition ambiguous — Conversion of 

 fossiliferous strata into metamorphic rocks — Limestone and shale of Carrara — 

 Metamorphic strata older than the Cambrian rocks — Others of Lower Silurian 

 origin — Others of the Jurassic and Eocene periods — Why scarcely any of the 

 visible crystalline strata are very modern — Order of succession in metamorphic 

 rocks — Uniformity of mineral character — Why the metamorphic strata are 

 less calcareous than the fossiliferous .... Page 611 



Chapter XXXVIII. — Mineral Veins. 



Werner's doctrine, that mineral veins were fissures filled from above — Veins of 

 segregation — Ordinary metalliferous veins or lodes — Their frequent coincidence 

 with faults — Proofs that they originated in fissures in solid rock — Veins shifting 

 other veins — Polishing of their walls or " slicken-sides" — Shells and pebbles in 

 lodes — Evidence of the successive enlargement and reopening of veins — Why 

 some veins alternately swell out and contract — Filling of lodes by sublimation 

 from below — Chemical and electrical action — Relative age of the precious 

 metals — Copper and lead veins in Ireland older than Cornish tin — Lead veins 

 in Lias, Glamorganshire — Gold in Russia, California, and Australia— Connec- 

 tion of hot springs and mineral veins — Concluding remarks - . 618 



SUPPLEMENT. 



British Pliocene Strata — Proofs from fossil shells of a gradual refrigeration of climate 

 in England, at the successive periods of the Coralline, the Red, and the Norwich 

 Crag — Searles Wood's Monograph on the Crag Mollusca — The Crag Mastodon, a 

 Pliocene species — Different assemblages of fossil Mammalia in the freshwater and 

 drift deposits of the valley of the Thames — Fossil Musk-buffalo in the drift near 

 London and near Berlin ______ Page 635 



Where to draw the line "between the Miocene and Eocene Tertiary Strata. 



Classification of the Miocene and Eocene strata— Where to draw the line between 

 Upper Eocene and Lower Miocene — Reasons for a proposed change of nomen- 

 clature — Miocene fossil shells and quadrupeds of the Sewalik or Sub-Himalayan 

 Hills 640 



Miocene Fauna of the Sewalik Hills ------ 645 



Denudation of the Wealden — Discovery of the Lower Crag on the summit of the 

 North Downs between Folkestone and Dorking - 645 



New Fossil Mammalia from the Purlech or Upper Oolitic Strata in Dorsetshire. 

 Discovery in Dorsetshire of seven or eight new genera of Mammalia in the Purbeck 

 or Upper Oolite strata — First example of a skull of a Mammifer from Secondary 

 Rocks — Insectivorous Marsupials and Placentals and herbivorous Marsupials — 

 Figures and descriptions — Light thrown on the Microlestes or oldest triassic Mam- 

 mifer — General bearing of the new facts - 647 



Discovery of Mammalian Remains in Rocks of high Antiquity in] North Carolina, 

 United States --------- 659 



Upper Trias of the Eastern Alps. — Recognition of a Marine equivalent of the Upper 

 Trias in the Austrian Alps — True position of the St. Cassian and Hallstatt Beds — 

 800 new species of triassic Mollusca and Radiata — Links thus supplied for connect- 

 ing the Palaeozoic and Neozoic faunas ----- 660 



On the supposed evidence of Phcenogamous Plants (not Gymnosperms) in the Coal 

 Formation --------- 663 



Silurian and Cambrian Rocks and M. Barrande's theory of Colonies - - 664 



Antiquity of Fossil Birds _____-- 669 



