THE CRETACEOUS FLORA 



OF 



SOUTHERN NEW YORK AND NEW ENGLAND. 



By Arthur Hollick. 



INTRODUCTION. 



SCOPE OF THIS MONOGKAPH. 



The flora described in this monograph belongs in part to the Raritan and in part 

 to the Chffwood formation of the Atlantic Coastal Plain Cretaceous, as represented in 

 southern New York, on Staten Island and Long Island, and in southern New Eng- 

 land, on Block Island and Marthas Vineyard in the States of Rhode Island and 

 Massachusetts, respectively, and these formations within the above-described geo- 

 graphic limits are collectively the equivalent of the "Island series" of Dr. Lester F. 

 Ward, as defined by him in his paper on the Potomac formation" (pp. 335, 336) as 

 follows : 



From Morgan [N. J.], the most easterly point, the formation may be traced northward across Staten Island 

 and the northern shore of Long Island, and it reappears on Marthas Vineyard in the celebrated cliffs of Gay 

 Head. At all of these points the stratigraphical evidence is strongly supported by paleontological evidence. 

 Along this most eastern line a new phase is seen, viz, the occurrence of concretions in the variegated clays, in the 

 form of hard ironstones, which when broken open are often found to contain vegetable remains in an admirable 

 state of preservation. I am therefore disposed to regard these ferruginous, concretionary beds, extending from 

 Staten Island to Marthas Vineyard, as the very latest phase of the Potomac formation, which I shall call the 

 Island series, although from the similarity in the flora I am disposed to include them, along with the Raritan 

 and Amboy clays, in the Albirupean series. 



Since the date when the above was written, our knowledge of the geology of the 

 region has been considerably enlarged by the discovery of new exposures and by the 

 critical examination and identification of the paleontological material collected, so 

 that we are now in a position to defuie with reasonable certainty the present and 

 probable former areal extent of the deposits of Cretaceous age in the region and to 

 correlate them more satisfactorily than heretofore with equivalent deposits elsewhere. 

 In this connection the evidence derived from fossil plants has been of greatest value, 

 and these it is the special object of this monograph to describe and discuss. 



oFifteenth Ann. Rept. U. S. Geol. Survey (1893-94), 1895, pp. 307-397. 



