162 The American Geologist. March, isoo. 
and that seven., not a single one^ of the abundant fossil plants 
occurring in the coal of Moquis, do not suffice to Dr. Newberry 
himself, notwithstanding his stricture on Taylor's view. . 
In 1843 William B. Rogers referred the "coal of eastern 
Virginia to a place in the Oolite system on the same general 
parallel with the Carboniferous beds of Whitby and Brora — 
that is, in the lower part of the Oolite group." ( On the age of 
the coal rocks of eastern Virginia, in "Trans. Assoc. Amer. 
Geologists," vol. i, p. 300, Boston, 1848). He based his views 
more especially on the Equisetuni cohimnare, Brong., 
Jceniopteris lohiibiensis and some Zamites- 
Charles Lyell, in 1847, in a paper entitled : On the struc- 
ture and pr oh able age of the coal field of the James river near 
Richmond^ Virginia. ("Quart. Jour. Geol. Soc. London," vol. 
Ill, p. 261) arrived at the same conclusion as William B. 
Rogers, adding : "If future researches should require any 
modification of this opinion, we may then expect that the 
Trias will be the group to which the American formation will 
be referable." Three fossil fishes collected by Lyell in Decem- 
ber, 1845, were referred by Agassiz to the age of the Lias. And 
C. J. F. Bunbury regarded the geological evidence afforded by 
the fossil j)lants as to a certain degree ambiguous. "On the 
whole," he says, "we may say with tolerable confidence that 
the Richmond coal field belongs either to the Triassic or to 
the Jurassic series." ("Quart. Jour. Geol. Soc. London," vol. 
Ill, p. 288). 
Henry D. Rogers, in 1848, read a paper before the British 
Association for the Advancement of Science, in Avhich he 
maintained the Jurassic age of the Richmond coal field, re- 
ferring it to the Inferior Oolite and even to the Great Oolite. 
Professor Newberry in his "Geological equivalents" p. 9 of 
the Mon. cit. says : "Profs. W. B. Rogers and H. D. Rogers 
were led by the general resemblance of the ferns and cycads 
of the Richmond basin to those of the Lias of Whitby, 
England, to consider these rocks Liassic, that is, Lower Juras- 
sic." The whole is incorrect, for the coal of Whitby has never 
been considered as belonging to the Lias, and was not called 
Liassic by the brothers Rogers, who did not refer the rocks of 
the Richmond basin to the Lias, but to the Lower Oolite and 
even to the Great Oolite. 
Such was our knowledge of the age of the eastern Virginia 
