On the Age of the Sandstones of the Newark Group. 357 



Art. XXYII. — On the Relations of the Fossil Fishes of the Sand- 

 stone of Connecticut and other Atlantic States to the Liassic and 

 Oolitic Periods; by W. C. Kedfield. 



Read before the American Association at Albany, Aug. 28, 1856. 



In the publications of Professor W. B. Sogers and Mr. E. 

 Hitchcock, Jr., on the red sandstone beds of Connecticut, New 

 Jersey and other States, founded on some of the contained fossils, 

 a higher geological position than that of the New Eed Sandstone 

 has been assigned to the formation by these writers.* Without 

 questioning their conclusions, I would here observe that the fossil 

 fishes of these rocks are the most characteristic and apparently 

 reliable fossils for determining the age of the formation. The de- 

 terminative value of these fossils is perhaps enhanced, also, by 

 the small vertical range to which some of the species, and at least 

 one of the genera, are probably limited. But these fishes, although 

 numerous as well as characteristic, do not appear to have been 

 referred to, in any manner, by the above named writers. 



Attention is invited, therefore, to a descriptive account of one 

 genus or group of these fishes, which was read to the New York 

 Lyceum of Natural History, in Dec. 1836, by Mr. John H. Ked- 

 field, and is found in vol. iv of the "Annals " of that Society. It 



* Prof. W. B. Rogers On the age of the coal rocks of Eastern Virginia, Am. Jour, 

 of Science, vol. xliii, p. 175, (1842). Also, in Proceedings of the Boston Society 

 of Natural History, vol. v, p. 14, (1864). — E. Hitchcock, Jr., M. D. in Arn. Jour, of 

 Science, vol. xx, (N. S.) p. 22, (1855). 



Prof. Rogers first assigns to the coal rocks of Eastern Virginia a position near the 

 bottom of the Oolite formation of Europe ; while from some fossils " discovered in 

 a particular division of the New Red Sandstone of Virginia," he expects to be able 

 confidently to announce the " existence of beds corresponding to the Keuper in 

 Europe," — doubtless in the extensions of the New Jersey Sandstones or Newark 

 group. I propose the latter designation as a convenient name for these rocks, and 

 those of the Connecticut valley, with which they are thoroughly identified by foot- 

 prints and other fossils, and I would include also, the contemporary sandstones of 

 Virginia and N. Carolina. 



At a later period, (1854) Prof. Rogers recognizes the general equivalency of the 

 eastern and middle belts of Virginia, and the eastern or Deep River coal belt of N. 

 Carolina : all of which in his view ought to be placed in the Jurassic series, not far 

 probably above its base. In relation to the more western belt, the occurrence of 

 Posidonise, and Cypridse, in Pennsylvania, with sauroid coprolites and imperfect im- 

 pressions of Zamites leaves, he considers as sufficient to identify, as one formation, 

 the disconnected tracts of this belt, in N. Carolina and Virginia and the prolonged 

 area of the so-called New Red Sandstone of Maryland, Pennsylvania and New Jer- 

 sey ; and that they are of Jurassic date, but little anterior to the coal rocks of 

 Eastern Virginia. 



Prof. H. D. Rogers (1839) proposed the name of middle secondary to this group 

 (for convenience sake) to distinguish it from the Appalachian formations on the one 

 hand, and from the green sand deposits on the other. — Third Report on Geol. of 

 Pennsylvania, p. 12. 



Mr. Hitchcock describes a new species of Clathopteris, discovered in the sandstone 

 of the Connecticut valley. This fossil fern, found near the middle of the series in 

 Massachusetts, he refers to the liassic period. 



