Cape May Formation — Local Details. 209 



portation of glacially derived gravels along the shore of the nar- 

 row bay thus formed. 



At the mouth of Mill Brook, on the north side of the river, 

 there are terraces comparable to those at the mouth of Lawrence 

 Brook on the south side, in both places at or near the 60-foot 

 level. The terraces at the mouth of Mill Brook contain no 

 glacial material brought down by the Raritan. 



Below South River, the Cape May formation has some repre- 

 sentation east of Sayreville, and thence along the bank of the 

 river to South Amboy, being confined to levels below 40 to 50 

 feet. Well-defined terraces are wanting. 



It is not demonstrable from the phenomena now presented by 

 this valley, either that submergence did or did not affect this 

 region in the last glacial epoch. It seems clear that glacial waters 

 went from Bound Brook up the Millstone at that time, either as 

 a river, or through a narrow strait. If the latter, they must 

 have gone down the Raritan also, cutting off the southern part 

 of the State from the northern by a narrow strait. The phe- 

 nomena farther south do not seem to give this hypothesis firm 

 support. 



South shore of Raritan Bay. — The Cape May formation has 

 little representation on the south shore of Raritan Bay from 

 South Amboy to Keyport, though it appears in a few small areas, 

 and in some places, as at Morgan, Lawrence Harbor and Cliff- 

 wood, in well-defined terraces, at elevations of 30 to 40 feet. 



South and east of Keyport its development is more consider- 

 able. It extends up Matawan Creek, reaching an elevation of 

 50 feet, a mile above Matawan. It covers a, considerable area 

 east of Keyport, mostly below an elevation of 40* feet, and ex- 

 tends up the valley of Waycake Creek for 4 miles. It is mostly 

 on the east side of the valley, and covers most of the lowland 

 (below 40 feet) between Keansburg and Bedford. Farther east, 

 it covers a belt from Atlantic Highlands across the peninsula 

 by way of Navesink and Clay Pit creeks, to Shrewsbury River, 

 rising to altitudes of 50 feet or so at its higher points. 



