1897 



ASHLEY — GEOLOGY OF ARKANSAS. 245 



Panther Bluff Locality. — At Panther Bluff on the Saline river in 

 6 S., 29 W., section -^-Ti^ shales are interbedded with sandstones, 

 and in these shales a fragment showing the peculiar ribbing and 

 jointing of the Calamites was found. This was the only specimen 

 found of which the genus could be determined with certainty. 



Saiifie River Locality near Antimofiy Cave. — Prof. Purdue found 

 fragments of plants on the Saline at the bend just above Arsenic 

 Cave in 7 S., 29 W., section 21. They are too poorly preserved 

 for identification. 



Animal Remains. 



Some fragments of crinoid stems and a few bryozoans, were 

 found in a loose quartzite boulder near the crossing of Antoine 

 creek by the Old Military road (8 S., 23 W., section 24). The 

 only other evidences of animal life found were what are thought to 

 be tracks of worms or crustaceans. These were found at two 

 localities in 5 S., 23 W., section 31, on the Amity-Kirby road, 

 a quarter of a mile west of the crossing of the North Fork of 

 Antoine creek, and also in section 14, on a knoll southeast of Sugar 

 Loaf mountain. 



Geologic Age of the Rocks. 



The age of the Silurian strata has been determined by means of 

 the numerous graptolites found in the shales associated with the 

 novaculite. The shales containing these graptolites have been cor- 

 related with the Norman's Kill beds of New York, and are referred 

 to the lower portion of the Trenton series.^ These fossils fix the 

 age of the Silurian beds. 



Of the fossils found in the overlying Lower Coal Measures rocks 

 only three have any diagnostic value : the two specimens of Cala- 

 mites and the stem found on the Caddo, which shows the leaf scars. 

 These plant remains are probably of Carboniferous age. The stems 

 and other fragments often found are of no value, as they might 

 occur anywhere from the Cambrian up, but from their association 

 on the Caddo with the stems believed to be Carboniferous, it has 

 been assumed that they belong to the Carboniferous, and that all 

 beds in this particular region in which they occur are Carboniferous. 



Upon the above grounds it has been thought safe to refer the 

 strata above the novaculites to the Carboniferous age. The grits 

 which cap the mountains along the northern face of the Boston 



1 Geol. Surv. of Ar/c., An. Rep. for 1890, Vol. iii, p. 418, e^ seq. 



