16 Journal of the Mitchell Society [September 



no intermediate developmental stages were found, and no adult 

 worm was found in the alimentary canal from which it could come. 

 The investigation of this organism is continuing. 



The Age of the Ocoee and Associated Rocks of Clay County, Alabama. 

 W. F. Prouty. 



The geological age of many of the rocks occurring in the semi- 

 crystalline area in the southern Appalachians has long been in doubt. 

 Dr. Safford of Tennessee, in 1856, assigned the Ocoee to the Pots- 

 dam Group (Cambrian). Arthur Keith of the U. S. Geological Sur- 

 vey, working in portions of Tennessee and North Carolina in more 

 recent times, demonstrated the conformity of the Ocoee with the 

 fossiliferous Cambrian. In 1903 Dr. Eugene A. Smith of the Alabama 

 Geological Survey discovered Carboniferous fossils in a small area 

 of the Talladega Phj^llites (the unquestioned equivalent of at least 

 a part of the Ocoee of Tennessee). 



It fell to the lot of the author to work out the relationship of 

 this small fossiliferous area to the associated rocks. This work was 

 carried on in the geological mapping of Clay County, Alabama. 



The area in which the Carboniferous fossils occur is considerably 

 faulted, but the fault block in which these fossils occur is connected 

 with and proves to be conformable to a series of dark slates and con- 

 glomerates underlying it with a thickness of several thousand feet. 

 From a careful study of the sequence of sediments in this area with 

 those in the Coosa and Cahaba Coal Fields, a little to the west, one 

 is brought inevitably to the conclusion that the conglomerate of Tal- 

 ladega Mountain just to the west of and geologically older than the 

 fossil l)eds is the Millstone Grit of the Pennsylvanian, and that the 

 underlying formations for some distance to the west, in the area of 

 the Ocoee (Talladega), are of Mississippian age. 



The Hillabee Schist, a metamorphic basic igneous rock, both cuts 

 across the strike of the Carboniferous Ocoee and intrudes it, thus 

 demonstrating its Post Carboniferous age. A little farther to the 

 east in Clay County areas of altered Talladega (Ocoee) of prob- 

 able Carboniferous age are intruded by the Pinkneyville granite, 

 thus suggesting if not proving their Post Carboniferous age. 



It is thus evident that the Ocoee is a group and that it includes 

 rocks varying in age from Cambrian to Pennsylvanian. It is also 

 evident that some of the larger areas of green schist in contact with 



