VI CONTENTS. 



Chapter II. — The Basement Complex, by W. S. Bayley— Continued. Page. 



Section 1. — The Xortherii Complex— Continued. 



The intrusives in the Northern Complex 1"8 



The basic dikes 1"8 



The acid dikes 182 



The peridotite 183 



The Presque Isle area 183 



The Opin area 184 



Ferruginous veins iu the Northern Complex 186 



Summary 188 



Section II.— The Southern Complex 190 



Distribution and topography 191 



Comparison with Northern Complex 192 



The schists 192 



Thi' micaceous schists , 195 



Muscovite-schists 195 



Biotite-schists 196 



Feldspathic biotite-schists 196 



Hornblendic biotite-schists 198 



Structure 198 



Composition and origin . 200 



The hornblendic schists 203 



Greenstone-schists 204 



Amphibole-schists 206 



Micaceous amphibole-schists 208 



Origin 208 



The gnei.ssoid granites 209 



Petrographical character 209 



Macroscopical 209 



Microscopical 210 



The Palmer gneisses 211 



Relations to adjacent formations 211 



Petrographical character 213 



Composition and origin 216 



Intrusives in the Southern Complex 218 



Summary 218 



Section III. — Isolated areas -n-ithin the Algonkian 220 



Chapter III. — The Lower Marquette series, by C. E. Van Hise 221 



Section I. — The Mesuard quartzite 221 



Distrilnition, exposures, and topography 221 



Folding 222 



Petrographical character 223 



Macroscopical 223 



Microscopical 224 



Relations to underlying formation 230 



Thickness 231 



Interesting localities 232 



Mud Lake 232 



