226 



large masses or concretions of a singular ferruginous sandstone 

 of a cellular structure. These occur in many places in the cliffs 

 of the Highlands of Nevesink, especially at' their southeast extre- 

 rrtity. In the cliffs neegr the mouth of the Nevesin|j river the 

 ferruginous sands contain also numerous hollow concretions 

 composed of the same brown mixture of sand and oxide of iron, 

 having the shape of bottles, flasks, and hollow balls or bombs; 

 and what is curious, these are full of white sand, the ferruginous 

 particles seeming to have been withdrawn from the sand within, 

 during the formation of this concretion. 



The nearly uniform height at which the yellow ferruginous 

 sand and the overlying brown sandstone occur, wherever they 

 are found in the greensand region and the tract bounding it on 

 the northwest, leads us to infer, that these beds were once conti- 

 nuous over the whole area at present occupied by the lower 

 members of the series. 



The denuding currents, which have removed so much of these 

 materials from the surface of the marl tract, have, in their pro- 

 gress towards the ocean, deposited apparently a large portion of 

 the looser particles, in a general diluvial covering, concealing the 

 strata, throughout the whole southeastern side of the southern 

 half of the Slate. 



The superficial sands thus derived occupy the area generally 

 known as the Pines. Constituting as they do the debris of strata 

 remarkable for their ferruginous composition, we can readily 

 account for the extensive deposits of bog iron ore, which they 

 furnish wherever circumstances favour a sufficient infiltration of 

 water through them. 



ORGANIC REMAINS OF THE UPPER SECONDARY STRATA. 



It is of little importance to the practical purposes of the present 

 report, to enter into any details respecting the numerous highly 

 curious fossils which abound in the formations, a general de- 

 scription of which I have now given. The most fossiliferous beds 

 are the greensand or marl stratum and the limestone, which so 

 generally reposes immediately upon it. The fossils from these 

 deposits, together with others from some equivalent formations in 

 the Southern States, are described with the requisite details in an 



