CONTENTS. 
Page. 
Introduction 7 
Geography 8 
Configuration 8 
Drainage : 9 
Climate 9 
Temperature 9 
Precipitation 10 
Geology 11 
Stratigraphy 11 
General relations 11 
Carboniferous system - 13 
Casper formation 13 
General character 13 
Thickness 13 
Local features 14 
Erosion and weathering of limestone slopes 18 
Paleontology and age 19 
Correlation 20 
Forelle limestone 20 
Satanka shale 22 
Triassic (?) system , 22 
Chugwater formation 22 
Character and distribution 22 
Local features 23 
( i y psiferous member 25 
Upper limestone 25 
Age 25 
J urassic system 26 
Sundance formation 26 
Occurrence and relations 26 
K< >ssi Is 27 
( Vetaceous system 27 
Morrison formation 27 
Distribution and general relations 27 
Character 28 
Fossils and age 29 
Cloverly formation 30 
Benton formation 32 
Distribution and general relations 32 
( 'luiracter 33 
Fossils 34 
Niobrara formation 34 
Montana group 35 
Distribution and general relations 35 
Character 36 
Fossils and age 37 
3 
