300 ON THE AGE OF THE 



would appear to have furnished the principal materials of the 

 sti'atum. No remains bearing any resemblance to Stigmaria have 

 been discovered either in the soft carbonaceous slates beneath, 

 above, or in the midst of the seams, or in the other slaty and 

 gritty strata of the series. 



With such a striking agreement, as regards not only the general 

 character of the vegetation, but the individual plants belonging to 

 the rocks now under consideration, and those of the Oolite coal of 

 Europe, it can scarcely be doubted that they were formed during 

 the same or very nearly the same geological period, and I there- 

 fore feel no hesitation in referring the coal of Eastern Virginia to 

 a place in the Oolite s//stem on the same general parallel imth the 

 carbonaceous beds of Whitby and Brora — that is, in the lower 

 part of the Oolite group. 



This determination possesses, I conceive, no small degree of 

 interest in its connection with our geology generally, inasmuch 

 as it supplies a very important link in the great geological suc- 

 cession of formations, which had not previously been discovered 

 anywhere within the United States. Nor is its importance less, 

 when connected with the striking discovery of Capt, Grant, of an 

 Oolite coal-series in the opposite hemisphere, near the mouth of 

 the Indus, some of the fossils of which appear to be almost iden- 

 tical with plants, from the Virginia coal rocks, hereafter to be 

 described."* With these discoveries in view, it can scarcely be 

 doubted that the fossil flora of even the middle geological periods 

 has sufficient uniformity of character, even in opposite parts of the 

 globe, to furnish a very useful guide in the comparison and iden- 

 tification of great geological groups. 



Of Animal remains, so abundant in the Oolite generally, the 

 only traces yet discovered in the Oolite coal series of Virginia 

 consist of teeth, apparently Saurian, recently found by me in and 

 a little above one of the coal seams in the northern pai't of the 

 district, and the scales and sometimes entire impressions of a 

 slightly Heterocercal fish, referred to, doubtingly, by Mr. Nuttall,t 



* See " Memoir to illustrale a Geological Map of Cutch." By C. W. Grant, Esq., 

 Trans. Geol. Soc. Lend., Vol. V., 2d series, 

 t See Trans. Acad. Nat. Sciences, Philadelphia. Vol. 3. 



