CONTENTS. 5 
Analyses— Continued. Page. . 
Igneous and crystalline rocks — Continued. 
Utah — Continued. 
2. Rocks from Henry Mountains 189 
3. Rocks from Bingham 190 
4. Rocks from La Sal Mountains 190 
5. Miscellaneous rocks 192 
New Mexico 193 
1. Basalts from the Rio Grande Canyon 193 
2. Mount Taylor region 194 
3. Colfax County 194 
4. Miscellaneous rocks 196 
Arizona 197 
1. Globe district 197 
2. Bradshaw Mountains quadrangle 199 
3. Morenci district 200 
4. Miscellaneous rocks 201 
Nevada 202 
1. Tonopah district 202 
2. Miscellaneous rocks 205 
California 209 
1. Mount Shasta 209 
2. Lassen Peak region 210 
Rhyolites 211 
Dacites and andesites 212 
Basalts 217 
3. Plumas County 220 
4. Butte County 223 
5. Sierra County 225 
6. Nevada City and Grass Valley 227 
7. Placer County 230 
8. Eldorado County 232 
9. Amador County 233 
10. Calaveras County 236 
11. Tuolumne County 236 
12. Mariposa County 240 
13. The quicksilver region 245 
14. Mount Diablo 247 
15. Miscellaneous rocks 251 
Oregon 255 
1. Basalt, Mount Thielsen 255 
2. Peridotite, Douglas County 256 
3. Crater Lake 256 
4. Port Orford quadrangle 260 
5. Miscellaneous rocks 263 
Washington 264 
Alaska 267 
British Columbia , 272 
Hawaiian Islands 272 
Guatemala 273 
West Indies 274 
Brazil ... 275 
Tasmania 276 
