POST-PALEOZOIC UPLIFTS. 311 



characteristic Silurian fault couise (north 25 degrees east), while the Post- 

 Paleozoic uplifts have affected them in common with the higher beds. Paleon- 

 tologically, the generic types are, perhaps, a little more near the Niagaran 

 than the Carboniferous, although the specific forms are commonly Upper 

 Devonian, and the composition of the beds is usually nearer that of the 

 higher system. Still, these generalizations do not always apply, and it may 

 be that further discovery will even enable us to construct an important transi- 

 tion system; for, in the northeastern part of Menard County, near the old 

 Pegleg Crossing of the San Saba River, south side, specimens of Dictyonema 

 fenestration, Hall, Loxonema, and Favosites were found in chert much like cer- 

 tain strata of the San Saba series, and the Devonian (if it be such) near 

 Marble Falls, in Burnet County, resembles the neighboring Silurian, carrying 

 also a Lower Devonian fauna in part. 



The provisional reference of this little known system to the Devonian is 

 based upon the occurrence of the following fossils: Dictyonema fenestration, 

 Hall, Aneimites, sp. ind., Psilophyton, sp. ind., Nozggerathia? (or Rhacophyllumf), 

 Taonurus (Spirophyton) caudagalli, Vanuxem, Aulopora serpuloidesf, "Winchell, 

 Cyathophyllum, Favosites, sp. ind,, Centronella, sp. ind., Aviculopecten duplicatus, 

 Hall, Discina senecaf, Hall, Bellerophon, Holopea, sp. ind., Loxonema solidum, 

 Hall, Dalmanites cegeria, Hall, Phillipsia, etc. 



THE POST-PALEOZOIC UPLIFTS. 



Much of the most interesting geology of our district is connected with 

 events of later date than those we have been discussing. While it is not in 

 the province of the writer to make detailed observations in Post-Devonian 

 territory, it happens that no observer in that field in Texas can completely 

 understand the dynamic history of his district without a knowledge of what 

 is revealed within our area. It is therefore very important to report here 

 such facts as have been collected bearing upon the later upheavals. In the 

 foregoing dissertation we have noticed all the classes of granite in Central 

 Texas, save two. Those which have not been mentioned occupy different 

 territory from the Pre-Niagaran uplifts. Leaving the details of Post-Devonian 

 history to be treated by those who have charge of that geology, it is proper 

 to state what are essential features of our district. The conclusions now to 

 be given are partly verified by the observations of Messrs. Cummins and 

 Tarr in the Carboniferous area northward, and of Mr. Hill in the Cretaceous 

 region upon the north and east, as I understand them. Within the core of 

 the Central Texas region, especially in the district hachured upon the pro- 

 gress map by vertical lines, the later uplifts are more extensive than the out- 

 bursts at the close of the Silurian. Excepting the secondary northwest 

 trend of that epoch, concerning which the collected evidence lacks precision, 



