4 INDEX TO THE STEATIGRAPHY OF NORTH AMERICA. 



Page. 

 Figure 10. Sketch map showing the distribution of Carboniferous rocks that are undivided on the geologic map 



of North America and the key to references in the text 356 



11. Sketch map showing the distribution of Mississippian rocks that are separately represented on the 



geologic map of North America and the key to references in the text 402 



12. Sketch map showing the distribution of Pennsylvanian rocks that are separately represented on the 



geologic map of North America and the key to references in the text 426 



13. Sketch map showing the distribution of Permian rocks that are separately represented on the geo- 



logic map of North America and the key to references in the text 475 



14. Sketch map showing the distribution of Triassic rocks and of undivided Triassic and Jurassic rocks 



that are so represented on the geologic map of North America and the key to references in the 



text 501 



15. Sketch-map showing the distribution of Jurassic rocks that are separately represented on the geo- 



logic map of North America and the key to references in the text 550 



16. Sketch map showing the distribution of Lower Cretaceous rocks represented on the geologic map of 



North America and the key to references in the text 580 



17. Sketch map showing the distribution of Upper Cretaceous rocks represented on the geologic map of 



North America and the key to references in the text 638 



18. Sketch map showing the distribution of earlier Tertiary rocks represented on the geologic map of 



North America andthe key to references in the text 707 



19. Sketch map showing the distribution of later Tertiary rocks represented on the geologic map of 



North America and the key to references in the text 795 



INSERTS. 



Page. 



Stratigraphy of the Pennsylvanian of Kansas, as interpreted by different authors 458 



Carboniferous formations in different parts of the western interior coal field 458 



Correlations in eastern interior coal region 468 



Correlation of the Cretaceous deposits of the eastern Gulf region and of the Carolinas 654 



Section of older Tertiary formations in Arkansas, Louisiana, and eastern Texas 724 



