CHARACTER OF THE^ RED BEDS NEAR BAINBRIDGE. 151 



folds between Wileys landing and the edge of the coast swamps appeared 

 to be not more than five or six, and as nearly as could be judged the 

 folds are successively higher, culminating at Alum bluff, which reaches 

 161 feet above low water by careful measurement. Part of this difference 

 in height may be due to the slope of the channel of the river seaward, 

 but it is probable that a moderate increase in absolute height does take 

 place. The bluffs along the river furnished convenient sites for Indian 

 villages, and shards of pottery, arrow-heads, flint chips, excavations and 

 other evidences of occupation are readily found. 



Localities in Detail. 



Bainbridge. — Professor Pumpelly * has recently described the remnants 

 of the Chattahoochee and Chipola beds which are found in various places 

 about Bainbridge superposed upon the Vicksburg Eocene rocks, from 

 which they are separated by an unconformity. These Miocene remnants 

 represent what is left after solution by water and carbon dioxide has 

 removed the greater jDortion, estimated by Professor Pumpelly as having 

 reached in some places a thickness of 200 feet. Only the silicified frag- 

 ments of rock and molds or siliceous pseudomorphs of the fossils now 

 remain. Over and partly including them is an extensive series of reddish 

 clays, sands and gravels, which of late have been referred to the Lafayette 

 formation of Hilgard and McGee, covered by yellowish gray incoherent 

 superficial sands (Columbian?) and a thin coating of humus. Else- 

 where in this paper (page 169) reasons are given for the belief advanced 

 by Professor Pumpelly that the red ])eds are of a composite nature, and 

 to a greater or less extent, depending upon locality, are made up of 

 residual material in its original location or but slightly transported by 

 aqueous' action. Tiie remnants of small quartz dikes broken up into 

 fragments but still retaining a nearly vertical position and of thin broken 

 siliceous sheets hardly moved from their horizontality in the gravels 

 seem to establish this fact beyond controversy. Elsewhere and espe- 

 ally on the upper surface of the red beds, worn and rounded material 

 testifies to a rearrangement and more or less transportation of part of 

 the original material. As further seaward similar material covers beds 

 later than the newer Miocene, it is probable that this part of the red beds 

 of this region is of not earlier than Pliocene age. 



Blue Springs. — At Blue springs, Flint river, Georgia, about four miles 

 below Bainbridge, limestones with Vicksburg fossils are the prevalent 

 rock, but above them Professor Pumpelly obtained fragmelits of highly 

 silicified rock containing casts of Orthaulax and Amauropsis hirnsii, be- 



* Am. Jour. Sci., vol. 46, December, 18'J.3, pp. 445-44T. 



