206 TRANSACTIONS OF THE WAGNER FREE 



These beds on the Neuse were referred by Kerr to the Quaternary/ under 

 the mistaken impression that the fossils contained in them were all of recent 

 species. It is probable that other beds of this sort occur near Cape Fear and 

 near the shores of the Sound, by Beaufort and east of the Pungo and Chowan 

 Rivers, judging from incidental remarks by Kerr and Emmons, and the nature 

 of the fossils described by Emmons and by Conrad. The latter boldly refers^ 

 " all those strata of sand and clay which border the Atlantic from Cumber- 

 land County, New Jersey, to the middle of South Carolina " to the " Miocene 

 Age." 



The discussion of the species in the beds above referred to is beset with 

 difficulty. The original method of determining the nomenclature of a divi- 

 sion of the Tertiary — by the percentage of living and extinct species of fossils 

 contained in them — has been practically abandoned. Tuomey reckoned that 

 42 per cent, of the species in his (composite) Pliocene were still found recent, 

 yet this did not prevent Conrad and Heilprin from regarding the beds as 

 Miocene. 



Since these authorities discussed the subject, the researches of the 

 U. S. Fish Commission have shown that a considerably larger number of them 

 are still living a short distance off shore, in less than 100 feet of water. A 

 more careful discrimination and comparison of the recent and fossil species 

 shows beyond question that the range of many species in time is far greater 

 than was formerly supposed, and that some species are still living which had 

 assumed their present characters in the Eocene. The comparison of the fauna 

 by parallelism with beds of known and admitted Miocene or Pliocene age, as 

 those terms have come to be used, is the plan to which we must resort. Yet 

 this is by no means easy, since large numbers of our so-called Miocene species, 

 and especially those with which these forms would be best compared, have 

 been described and catalogued without that particularity of location which 

 alone would enable us to decide whether their Miocene character was really 

 beyond dispute. I have been obliged, therefore, in the assignments of age 

 tabulated below, to depend upon collections of more recent date for decision 

 on such points ; and as quite a number of species are still to be precisely 

 located, the results are liable, with further information, to be slightly modified. 

 In the present case, however, the evidence is so strong that it would seem that 

 such modifications, in any event, could not change the main conclusions to 

 which the study of the fauna has led me. 



In the publication to which I have already referred,"* I have endeavored 

 to correlate the names heretofore assigned to the subdivisions of our Tertiary, 

 with the ph3^sical changes which are indicated by the stratigraphic and faunal 

 unconformities which characterize them. The continuity of deposition in the 



' Report of the Geol. SurTey of North Carolina, p. 155, 1675. 

 2 Rep. Geol. Siirv. N. C, 1875, App. A, p. 24. 

 = Bull 81, U. S. Geol. Survey. In press 



