CRETACEOUS FORMATION OX STATEN ISLAND. 417 



Series " was given by Dr. Lester F. Ward to the strata repre- 

 sented on these islands.' 



The "Island Series" would therefore lie above the Amboy 

 clays as described by Newberry,^ and below those of the clay 

 marls at Clifford, as described by me in a recent paper.^ 



The sequence of the strata and their relations to the localities 

 where they are prominently exposed may be understood from 

 the following table : 



Geological Horizons. 



Strata. 



New Jersey Localities. 



Matawan. 





Cliffwood. 





Island Series. 



Morgans. (?) 



Upper Potomac 

 (Amboy CI ays j. 



Albirupean Series. 



South Amboy. 

 Perth Amboy. 



Sayreville. 

 Woodbridge. 



-> 



(" Iron Ore Series" ?) 





Middle Potomac. 



Acquia Creek Series. 



Not known in New 



Basal Potomac. 



Mount Vernon Series. 



Rappahannock Series. 



James River Series. 



Jersey. 



Whether or not all of Dr. Ward's conclusions will stand, ap- 

 pears to me, will depend upon future investigation. Thus far I 

 have failed to find the equivalent of the Island Series on the 

 mainland of New Jersey in the region where it should theoretic- 

 ally occur, nor have the ferruginous concretions and fragments, 

 by which the series is characterized on the islands, been found 

 there, and the fact of their absence on the mainland, and their 

 presence on the islands only in connection with the terminal 



1 The Potomac Formation, 15th Ann. Kept. U. S. Geol. Surv., 335, 336, 



2 The Flora of the Amboy Clays, Mono'g. U. S. Geol. Stti'v., XXVI. 



^The Cretaceous Clay Marl Exposure at Cliffwood, N. J., Trans. A'. Y. Acad. 

 Sci., XVI (1897), 124-136. 



