LIST OF ILLUSTRATIONS. 



Platb a. — Mammoth. Hot Springs, Gardiner's Eiver ..o... Frontispiece. 



GEOLOGY. 



Accompanying Eeport of William H. Holmes. 



Facing page — 



Plate B. — GraiMi Canon of the Yellowstone 1 



I. — Yellowstone Lake 2 



11. — Geologic section showing displacements, Yellowstone Valley.. 4 



III. —Map showiug displacements, Yellowstone Valley 6 



IV. — Geologic sections showing displacements, Yellowstone Valley. 8 



V. — Intruded Basalts, Mount Evarts 10 



VI. — Intruded Basalts, Mount Evarts • 10 



VII. — Contact of Rhyolites with Cretseceous rocks, Mount Evarts. .. 12 



VIII. — Southern end of Gallatin Range 18 



IX. — General view of Gallatin Eange 20 



X, — Section through Electric Peak, Sepukhre Mountain, and Mount 



Evarts 20 



XI. — ^Volcanic conglomerates. West Gallatin Mountains 22 



XIIL— The Indian Creek Laccolite 24 



XIV. — Longitudinal section of East Gallatin Range 26 



XV. — ^View of border of Park Plateau from ■Quadrant Mountain 28 



XVI. — Implements of Obsidian 30 



XVII. — Section through Mount Washburn 32 



XVIII. — Canon of the Yellowstone at the foot of Mount Washburn 34 



XIX. — A portion of the Cafion wall 3t» 



XX. — A portion of the Cafion wail 38 



XXI. — Section Canon wall near Agate Creek 38 



XXII. — Geologic map of Junction Valley 42 



XXIII. — Panoramic view of Junction Valley 44 



XXIV. — Sketch showing Basalts, Junction Valley 44 



XXV. — Basaltic columns opposite the mouth of Tower Creek 4G 



XXVI. — Geologic sections. Junction Valley 4(! 



XXVII. — Section of Amethyst Mountain 48 



XXVIII.— A^alley of Soda Butte Creek 50 



XXIX. — Stratified conglomerates near the head of the Yellowstone 50 



XXX. — Map showing distribution of glacial bowlders 52 



XXXI. — Map showing outline of ancient Yellowstone Lake 56 



XXXII. — Panoramic views in the Park. 



Geologic map of the Park (in accompanying pocket). 



xm 



