98 PROCEEDINGS OF THE ACADEMY OF [1895. 



Tyler and Polk Counties, is broken and hilly and generally rough, 

 many of the hills rising in the form of steep side knobs to elevations 

 more than 150 feet above the level of the river bottoms. The Neches 

 River flows along the northern border of these sandstones for nearly 

 twenty miles before breaking through them near Rockland, and 

 along the whole of this distance the Fayette sands rise almost pre- 

 cipitously from near the river bank to altitudes varying from 120 to 

 275 feet above the river. 



The dip of these beds is gentle, as a whole, but in many places 

 faulting and sliding has obscured the true dip to such an extent that 

 it is difficult to tell its exact rate. Extensive erosion also appears 

 to have taken place throughout the whole. area and long narrow pro- 

 jections of the overlying Neocene beds appear in many of the 

 valleys. Along the eastern side of Billum's Creek, about two miles 

 west of Colmesnil, a ridge of brown sand and quartz gravel and 

 coarse pebbles, fifteen feet thick extends in a northeastern direction, 

 for several miles. 



The Fayette sands of Eastern Texas tie up both stratigraphically 

 and lithulogically in the northern portion of Washington County, on 

 the western side of the Brazos with those recently described as 

 occurring from that point westward across the State by Mr. Dumble, 24 

 and may be considered but an eastern extension of the same. 



There can scarcely be any doubt but that these beds, with the Frio 

 clays and overlying Neocene ("Navasota Beds" of the Fourth Annual 

 Report and Dumble's ' 'Oakville Beds" 25 ) formed what was under- 

 stood by Hilgard, Hopkins, Loughridge and others to be the western, 

 or Texas, extension of the Grand Gulf beds and considered of 

 Miocene age. Whether the Neocene division as seen in the Navasota 

 beds of'theeastor the Oakville beds of the west maybe correlated with 

 the Grand Gulf beds or not, future investigation must decide, but 

 manifestly with the evidence at present before us no such correlation 

 can be made as far as the Frio clays and Fayette sands are concerned. 

 There can be no doubt as to their Eocene age, and moreover, a great 

 hiatus occurs between the lowest Neocene beds and the highest Eocene 

 deposits represented in the section as the whole of the Vicksburg and 



-' Fourth Annual Report Geol. Survey of Texas, 1892, pp. 9-15. 

 20 Journal of Geology for Sept., 1894, pp. 557-558. 



