Bridgeton Formation — Local Details. 45 



lies at the base, on the Cohansey sand. Bowlders up to 3 feet 

 in diameter on the floor of the pit apparently came from this 

 basal bed. The largest bowlders are of brownish sandstone, of 

 a type common throughout southern New Jersey. 



The low altitude of this gravel and sand at Buck Hill raises the 

 question whether it is not younger than Bridgeton. So far as its 

 position is concerned, it might be Pensauken, or even Cape May ; 

 but at this locality, there are slabs of shale, even up to 2 feet in 

 diameter, at the base of the formation, in precisely the same 

 relations as at Folsom. This material, in this position, is so 

 distinctive as to point strongly to its correlation with that at 

 Folsom. Similar materials have never been found in the Cape 

 May formation, or in the Pensauken formation southeast of the 

 Amboy-Bordentown-Delaware valley lowland, if present cor- 

 relations are correct. 



The character and condition Oif the Triassic slabs at Buck Hill 

 is such as to' preclude the idea that this material has been re- 

 worked since its deposition. The general character of the forma- 

 tion is such as to rule out the Cape May formation at sight. 

 This youngest of the Coastal Plain formations is everywhere com- 

 posed of fresh, undecomposed material, whereas the decayed 

 condition of everything that will decay is conspicuous at Buck 

 Hill. Furthermore, the altitude of the gravel at Buck. Hill is in 

 keeping with the altitude of the Bridgeton to the northwest 

 where it is characteristically developed. The same formation 

 occurs at various intermediate points at harmonious levels, as at 

 Russia, Doughty's, Richland, Newtonville, and Williamstown. 

 In other words, if we project a line from Cross Keys at 150 feet, 

 to Buck Hill, at 40, it will correspond closely with the base of 

 the Bridgeton at all intermediate points. 



Between the headwaters of Maurice River and Great Egg 

 Harbor River. — Maurice River has its source near Glassboro 

 and Cross Keys and flows to Delaware Bay at Port Norris. 

 Great Egg Harbor River has its source a few miles farther 

 northeast, near Berlin and Williamstown. In the area between 

 the upper parts of these drainage systems, north of the head- 

 waters of the Manantico and Manumuskin creeks, there are 



