354 W. B. CLARK — UPPER CRETACEOUS FORMATIONS OF NEW JERSEY. 



Lignitic may have antedated the lower bed of the Pamunkey, but that 

 is not at all sure. 



Let us now return to a consideration of the Rancocas-Manasquan-Shark 

 River formations. The Rancocas fauna, so far as its generic forms are 

 concerned, as well as in a few instances of specific identity, is clearly 

 Cretaceous, but from its position is later than the Ripley. The Manas- 

 quan fauna, which succeeds it in conformable deposits, is far less typically 

 Cretaceous, although it could hardly be associated with the Eocene, while 

 the conformably succeeding Shark River bed, only 12 feet in thickness, 

 has a fauna which shows unmistakable Tertiary affinities. 



It seems highly probable that the conformable Rancocas-Manasquan- 

 Shark River group may occupy a position between the Ripley and the 

 Lignitic of the Gulf, and may be in its two basal members of Cretaceous 

 and in its upper member of Eocene age. Clearly defined unconformity 

 exists between the Ripley and the Lignitic, and during the interval rep- 

 resented by this physical break deposition must have taken place some- 

 where along the continental border. It is highly probable that the 

 Rancocas-Manasquan-Shark River group represents the whole or a part 

 of this interval (plate 50). 



To the nOrth of New Jersey there are many indications of the former 

 wide extension of the Upper Cretaceous formations. On both Staten 

 island and Long island, fossils belonging to the Matawan-Monmouth 

 fauna have been obtained from the drift, while the deposits are still found 

 in place on Block island, Marthas Vineyard, and at Marshfield, in Mas- 

 sachusetts. It seems highly probable that the deposits of all these locali- 

 ties belong to the Matawan formation. To the south of Maryland, 

 in eastern Virginia, the upper Cretaceous has been penetrated in well- 

 borings, but the records are not sufficiently complete to determine the 

 horizons with accuracy. In North and South Carolina the presence of 

 the upper Cretaceous has been known for a long time. The fossils de- 

 scribed from this district show that the Matawan-Monmouth fauna is 

 represented, but it is not certain whether the same divisions exist there 

 as in the northern Atlantic states. Nothing similar to the higher forma- 

 tions of the upper Cretaceous in New Jersey and Maryland has appar- 

 ently been observed. 



Some statements regarding the approximate equivalents of these Amer- 

 ican formations among western European deposits may well close this 

 chapter. Any attempt at a detailed correlation of the strata must, from 

 the necessities of the case, be fraught with many difficulties. Almost 

 none of the species are identical, yet the assemblage of forms is such as 

 to warrant the conclusion that we have in the New Jersey formations 



