XIV ILLUSTRATIONS. 



Fig. 17. Twomey Greek disturbances 241 



18. Section of iron ore deposit four miles north of Timpson 249 



19. Wolf Mountain sandstone 253 



20. Faulted lignite bed 254 



21. Section at Sulphur Spring, Rusk County 264 



22. Ideal section of oil bearing region. Nacogdoches County 214 



23. Section one mile southeast of Fitze Station 282 



24. Section near brickyard at Nacogdoches . . . 283 



25. Oil bearing greensand marl 284 



23, 24. Temnocheilus conchiferous 329 



25, 26. Temnocheilus depressus 331 



27, 28, 29. Temnocheilus crassus 333 



30, 31, 32, 33. Metacoceras cavatiformis 334 



34, 35. Metacoceras dubium 336 



36, 37. Metacoceras walcotti 336 



38, 39. Metacoceras hayi 339 



40, 41. Metacoceras inconspicuum 340,. 34] 



42, 43, 44. Tainoceras cavatum 341 



45, 46, 47. Damatoceras umbilicatum 343, 344 



48, 49. Asymptoceras newloni 346 



50, 51. Phacoceras dumbli 347 



52, 53, 54. Ephippioceras divisum 350 



55, 56. Bndolobus gibbosus 353 



57, 58. Gastrioceras compressum 355 



59. G-astrioceras compressum 355 



60, 61. Hadrophyllum aplatus 552 



62. Section|through Northern Copper Field 579 



63. Section crossing Mason Copper Field 581 



64. Section crossing most southern Burnetian folds 583 



65. Section of lead region of northwest Burnet County. 585 



66. Section of lead district north of Hye ....... 586 



67. Section crossing Caylor tract, Mason County 587 



68. Complications in structure at eastern end of tin belt 601 



69. Neighborhood of Shaft Mountain, Mason County 601 



70. Spiller mine, Mason County 603 



