28 



thickness from ten to thirty feet. Virginia seems to be the region of 

 change for this formation. In the region to the west and north of 

 Washington, the earlier Columbia is at high altitudes, and the later 

 lies on the low terraces in the deeper portions of the depressions, but 

 to the east and south the later Columbia lies in regular succession on 

 the earlier. As we go farther south from Virginia,- the later Colum- 

 bia advances more upon the earlier, and in South Carolina, where it 

 is almost impossible to make any division at all, perhaps it is that 

 the later has entirely overlapped the earlier. 



NORTH CAROLINA. 



In this State the interfluvial phase of the Columbia has almost 

 eclipsed the fluvial in extent and in importance. The Pleistocene 

 formation here is so closely similar in occurrence and in composition 

 to the same formation in South Carolina that it need not be spoken 

 of at length. About 1840 Conrad wrote a description of a Pleisto- 

 cene locality on Neuse River, and gave a list of the fossils found 

 there 1 , thirty-four in number. But upon further investigation this 

 locality has been classed as Pliocene within late years. However, 

 there are some fossiliferous Pleistocene beds along the coast of North 

 Carolina. As in South Carolina, these beds are confined to a belt 

 along the shore extending inland only a few miles. 



SOUTH CAROLINA. 



Inasmuch as a separate discussion of the Pleistocene of this State 

 is to be given in this paper, nothing further need be said concerning 

 it here. 



GEORGIA. 



Very little has been done upon the geology of the Coastal Plain 

 of this State. But Couper and McCallie have given brief descriptions 

 of the region, and McGee, in "Lafayette Formation," gives a few 

 pages to Georgia. The Coastal Plain extends over all that part of 

 Georgia lying south of a line running from Augusta westward across 

 the State by Columbus and Macon. Here, as elsewhere along the 

 margin of the region, the different formations advance in varying 

 degree. The Pleistocene sometimes comes so far inland as to rest 

 upon the Piedmont crystallines, and at other places upon the Potomac, 



1 "Observations on a Portion of the Atlantic Tertiary Region, etc' 

 (National Inst. Proc., Vol. I, pp. 171-94). 



