RUSK COUNTY. 267 



The direction of the pressure cracks in the marl, the direction of the pres- 

 sure cracks in the lignite in the western portion of Shelby County, and fault- 

 ing disturbance at Grand Bluff, on the Sabine River, are nearly if not quite 

 in parallel lines, and not many miles apart. The inference may fairly be 

 drawn that they were closely connected phenomena and belong to the same 

 time. 



This inference becomes more important in consideration of the probability 

 that the Eocene epoch ended with the formation of the iron pebble conglom- 

 erate which now caps or has capped the hills and ridges of highest elevation, 

 and that a period of grand erosion, accompanied with a land elevation or sea 

 subsidence, intervened between the formation of the iron pebble conglom- 

 erate and the estuary deposition of the calcareous greensand shell marl. 



The writer is indebted to Dr. W. D. Holleman and Esquire L. D. Stevens 

 for courtesies received during several trips in this region. 



