1S07.] ASHLEY — GEOLOGY OF ARKANSAS. 243 



Little Missouri, the grit appears about four hundred feet above the 

 black novaculite. In the Cossatot section it appears east of the 

 river just below the shales and not more than six hundred feet 

 above the black novaculite. This, together with the fact that it is 

 usually found elsewhere close to the anticlines, indicate that it is 

 not far above the novaculite, probably within a few hundred feet. 

 Its relation to surrounding beds varies greatly : in places it is just 

 below thick beds of shale, in other places it is just below thick 

 beds of sandstone ; hardly any two exposures agreeing, so that 

 while lithologically it is very similar wherever found, it is quite 

 possible that the different exposures are only local in extent and 

 occur in different horizons. In several places, however, the grit 

 has been traced in more or less continuous exposures for several 

 miles. 



A General Section. — Could we construct a general section it would 

 be somewhat as follows : 



5. Sandstones forming top of exposed beds and having a thick- 

 ness at one place of four thousand feet or more. 



4. A variable set of beds of shale and sandstone measuring at 

 least several hundred feet in which occur, 



(«) A bed of beds or grit. 



(^) A thin bed of novaculite and silicious shales. 



3. A bed probably of igneous origin, thirty-three feet. 



2. A thin bed of novaculite breccia. 



I. Silurian novaculites, shales and sandstones. 



IV. Fossils and Age of the Strata. 



Caddo River Locality. — The first and most promising locality at 

 which plant remains were found is in 5 S., 21 W., on the tongue 

 of land just east of the mouth of Point Cedar creek. There is here 

 a goodexposure of black, carbonaceous shale having a peculiar 

 hackley fracture. This contains a great many minute fragments of 

 plants. Only a few are large enough to show any characters ; of 

 these the most common are long stems showing no branches, but 

 ribbed longitudinally. These stems average a quarter of an inch 

 in width by several inches in length. They are the most common 

 fossils found in the area. They occur at several places, but at none 

 of these places were any obtained which would permit a closer 

 identification than that they were the stems of some plant. There 



