CONTENTS si 



4. Percentage of Living and Extinct Species 195 



5. The Wabash Fauna 195 



PART II 



REVIEW OF OUR KNOWLEDGE CONCERNING THE LIFE OF THE 



GLACIATED AREA DURING THE PLEISTOCENE OR 



GLACIAL PERIOD 



Chapter V. Preglacial Conditions and Lite 



1. Ancient Drainages 197 



a. The Basins of the Great Lakes and the Buried River Valleys 197 



b. Ancient Rivers with Reversed or Altered Modern Drainage 199 



2. Preglacial Life of the Glaciated Area 202 



a. Fish-house Clay Fauna and Flora, New Jersey 203 



i. Section of Strata at Fish-house 203 



ii. Life of the Fish-house Clay 204 



hi. Age of the Fish-house Clay 206 



b. Port Kennedy Cave Fauna and Flora, Pennsylvania 207 



c. Hay Springs Fauna, Nebraska 209 



d. Other Faunal Areas 209 



3. Catalog of the Preglacial Biota Referred to in this Chapter 211 



4. Summary 215 



Preglacial Conditions of the Glaciated Area 215 



Preglacial Biota 215 



Chapter VI. The Glacial or Pleistocene Period 



1. Effect of the Ice on the Topography 216 



2. Effect of the Ice on the Biota 216 



3. The Ice Invasions 219 



a. Interglacial Life and Conditions 219 



b. Imbrication of Drift Sheets 220 



c. Age of the Drift Sheets 221 



d. Centers of Ice Accumulation and Radiation 221 



e. Effect of Glaciation on the Englaciated Territory. 221 



f . Length of Time since the Earliest Ice Invasion 222 



4. Summary 223 



Chapter VII. The Nebraskan Ice Invasion and the Aftonian Interglacial 

 Interval 



I. The Nebraskan Ice Invasion 224 



II. The Aftonian Interglacial Stage 2 24 



A. Organic Remains 224 



a. Typical Exposures of Deposits 225 



b. Typical Aftonian Fauna 225 



c. Distribution of the Aftonian Biota 227 



1. Iowa 227 



2. Nebraska 232 



3. Missouri 232 



4. Kansas 234 



