origin--Chemically and organically formed rocks--Calcareous
rocks--Chalk, its microscopic structure and mode of
formation--Limestone, varieties, structure, and origin--Phosphate
of lime--Concretions--Sulphate of lime--Silica and siliceous
deposits of various kinds--Greensands--Red clays--Carbon and
carbonaceous deposits.

CHAPTER III.

Chronological succession of the fossiliferous rocks--Tests or age
of strata--Value of Palæontological evidence in stratigraphical
Geology--General sequence of the great formations.

CHAPTER IV.

The breaks in the palæontological and geological record--Use of
the term "contemporaneous" as applied to groups of strata--General
sequence of strata and of life-forms interfered with by more or
less extensive gaps--Unconformability--Phenomena implied by
this--Causes of the imperfection of the palæontological record.

CHAPTER V.

Conclusions to be drawn from fossils--Age of rocks--Mode of origin
of any fossiliferous bed--Fluviatile, lacustrine, and marine
deposits--Conclusions as to climate--Proofs of elevation and
subsidence of portions of the earth's crust derived from fossils.

CHAPTER VI.