CONTENTS. IX 



Pp.se. 

 :>'eueopteiu. : 



Mesotbemis composita 728 



Myrmeleon diversiis , - - 729 



ilALLOPHAGA : 



Menopoa pici<3oIa 731 



Goniodes Merriamamis 731 



mephitidis 732 



Niimus buteonivorus - 733 



Docophorns syrnii 733 



Parasitic worms : 



Eustrongylus buteonis 735 



cbordeilis 736 



Akachntda : 



Argas Americana - 740 



PLAIS'TS : 



Dicentra uniflora 760 



Peziza Vulcaualis 792 



Spbeeria Coulteri 792 



LIST OF ILLUSTRATIONS. 



WOOD-CUTS. 



'So. Page. 



1. Modem lake deposits, capped wiftb basalt, two miles above Boteler's Ranch, 



valley of tbe Yellowstone 29 



2. Tracliyte dike, and columns of breccia, Yellowstone Valley 37 



3. Volcanic tuffs and breccia, Yellowstone Valley 38 



4. Volcanic breccia at the bead of Canon and Rock Creeks 39 



5. Section of vertical strata at Cinnabar Mountain and Devil's Slide 41 



6. Extinct geyser. East Fork of tbe Yellowstone 45 



7. Carboniferous limestone section of Soda Butte 46 



8. Index and Pilot Peaks 47 



9. Basaltic columns, Yellowstone, near mouth of Tower Creek 50 



10. Yellowstone Lake, (east side) 51 



11. Wall of basalt, Yellowstone River, at Mud Springs 51 



12. Hot spring, southwest of Yellowstone Lake 52 



13. Camp of United States Geological Survey, on shore of lake 53 



14. United States Geological Survey en route 53 



15. Yellowstone Geysers 54 



16. Terraces, valley of the Madison ! 62 



17. Banded gneiss ^ ., '. 67 



18. Dike on the Missouri J 68 



19. Exposure of Silurian shales, eight miles below the Three Porks . 69 



20. Section across the Missouri below the Three Forks 71 



21. Connection between Missouri and Gallatin 72 



22. Silurian beds of the Gallatin 73 



23. Deceptive weathering, Liberty Peak 76 



24. Section through Flathead Pass 84 



25. Block of granite with feldspathic seams 106 



26. Arch in Spring Canon 109 



27. Section of the beds in Spring Canon 110 



27«. Section from Spring Canon to Bridger Peak 113 



28. Section of coal-bed 114 



29. Second canon of tbe Yellowstone River 119 



