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Bancroft Library 



CONTENTS. 



LETTER OF TRANSMITTAL ix 



PREFACE xi 



OUTLINE OF THIS VOLUME xv 



CHAPTER I. General description 1 



CHAPTER II. Geological sketch of the Eureka District 8 



CHAPTER III. Cambrian and Silurian rocks 34 



CHAPTER IV. Devonian and Carboniferous rocks 63 



CHAPTER V. Descriptive geology 99 



CHAPTER VI. General discussion of the Paleozoic rocks 175 



CHAPTER VII. Pro-Tertiary igneous rocks 218 



CHAPTER VIII. Tertiary and post-Tertiary volcanic rocks 230 



CHAPTER IX. Ore deposits 292 



APPENDIX A. Systematic lists of fossils of each geological horteon. By C. D. Walcott 317 



APPENDIX B. Microscopical petrography of the eruptive rocks. By .1. P. Iddings 335 



INDEX 407 



v 



