TABLE OF CONTENTS.


TRENTON PERIOD - Subdivisions of - TRENTON EPOCH - Synoptical notes on
Trenton formation - Life of the epoch - Plants - Corals - Lower forms -
Crinoids - Brachiopods - Lamellibranchs - Gasteropods - Heteropofs -
Pteropods - Cephalopods - Annelids - Crustaceans - Trilobites - General
remarks on life - Contribution of life to rock-formation - Dolomization -
Subdivisions of Trenton limestone - Lower Buff limestone - Lower Blue
limestone - Upper Buff limestone - Upper Blue limestone - Metallic de-
posits - Lead and zinc - State and continental distribution,  -  151-165
GALENA EPOCH - Synoptical notes on the Galena limestone - Oceanic condi-
tions - Central arch - Life - Characteristic fossils - Rarity of fossils
-
Their scarcity explained - Variations in the formation - Distribution, state
and continental - Equivalency of Galena limestone and the Utica shale,
165-170
HUDSON RIVER EPOCH - Synoptical notes on the formation - Character of dep-
osition - Thickness of Hudson River shales - Stratification - Ripple marks
and mud cracks - Life - Corals - Mollusks - Colonial character of life -
Arching of strata - Cincinnati arch - Disturbances closing the Lower Silu-
rian-Probable land surface- Geography at close of Hudson River epoch-
Land - Plants - Climate - Distribution of Hudson River shales - Foreign
equivalents of Lower Silurian, --170-177
CHAPTER IX.- UPPER SILURIAN AGE.
Subdivisions - Interval between Hudson River and Clinton epochs - CLINTON
EPOCH - Synoptical notes on Clinton iron ore - Thickness - Localities of
Character of the ore - Its richness - Fossils -Method of formation - Cor-
relation,                                      -   -   -    178-181
NiAGARA EPOCH - Synoptical notes - Subdivisions - Basal deposits - Coral
reefs - Life about reefs - Formations adjacent to reefs - Deposits north
of
the reefs - Mayville beds - Waukesha beds - Racine beds - Byron beds -
Lower Coral beds - Upper Coral beds - Racine beds - Guelph beds -
Thickness of Niagara formation - Life of the epoch - Plants - Proto-
zoans - Corals - Crinoids - Bryozoans - Brachiopods - Lamellibranchs -
G-asteropods - Heteropods - Cephalopods - Crustaceans - Comparison with
previous faunas - Colonial tendencies of Niagara life - Distribution of the
formation, --181-196
LOWER HELDERBERG EPOCH - Occurrence of Lower Helderberg rocks in Wis-
consin - Fossils - Salina epoch - Correlation - Distribution of the forma-
tion - Close of Silurian age - Life progress - Foreign equivalents of Upper
Silurian rocks - Interval between Lower Helderberg and Hamilton periods,
197-200
CHAPTER X.- THE DEVONIAN AGE.
Subdivisions - HAMILTON EPOCH - Synoptical notes on Hamilton formation -
Conditions and character of deposition - Milwaukee cement rock - Life -
Vertebrates - Insects - Land plants - Invertebrates - Last oceanic deposi-
tion in Wisconsin - Distribution - Foreign equivalents of Devonian, 201-206
Summary observation on the Wisconsin Palaeozoic series - Groups of deposits
-
Order of succession - Cycles of deposition - Period and epoch defined -
Life progress, -  -   --207-212


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