346 MESOZOIC FLORAS OF UNITED STATES. 



The paper by Nuttall from which Mr. Taylor takes the above state- 

 ment appeared in the Journal of the Academy of Natural Sciences of 

 Philadelphia, Vol II, Pt. I, 1821, and the statement occurs on page 37. 

 "On examining the context I am satisfied that the fossil wood described 

 came from the Older Mesozoic and is of the same age as the Richmond 

 coals and not of Potomac age." 



In this same year (1835) was begun the important series of reports 

 by Prof. W. B. Rogers, State geologist of Virginia, on the geology of that 

 State. In the first of these, which was only a reconnaissance, he devotes 

 a section to the "sandstones overlying the Primary rocks along their 

 eastern boundary,"" in which he describes the Older Potomac beds in 

 the vicinitjr of Fredericksburg and below Richmond and Petersburg, 

 mentioning the Aquia Creek quarries. He says that "in the superior 

 portion of these beds lignites, silicified wood, and vegetable impressions 

 are frequently to be seen — all of which contribute to render the exam- 

 ination of these deposits a subject of much curious interest to science." 



Professor Rogers did not again discuss the beds of this age until 1840. 

 In his report for 1839* he characterizes it as the "Sandstone foi'mation" 

 (p. 20), and traces it as far south as Boilings Bridge on the Nottaway 

 River (p. 17). In his next report" he devotes most of Chapter III to 

 this formation, which he first describes as "The narrow belt extending 

 along the eastern margin of the primary from Petersburg to the Potomac 

 River (p. 26), and afterwards designates the "Upper Secondary" (p. 29). 

 He devotes a section (Sec. II) to bounding the formation and another 

 (Sec. Ill) to describing its characters and contents. He sometimes 

 speaks of the freestone as "loose-grained feldspathic sandstone" and 

 accurately describes its mineralogical character, but does not make use 

 of the term " arkose." On page 36 he takes some pains to show that these 

 beds are not the same as, and are younger than, the coal basins of Henrico, 

 Chesterfield, etc., counties, now known as the Richmond coal field, but 



« Eeport of the Geological Reconnaissance of the State of Virginia, made under the appointment of the 

 board of public works, by William B. Rogei-s, Philadelphia, 1836, p. 61. 



It should be stated that this and all the subsequent reports of Professor Rogers are literally reprinted in a 

 much more accessible form in the volume entitled, A Reprint of Annual Reports and other Papers, on the 

 Geology of the Virginias, by the late William Barton Rogers, New York, 1884. 



^ Report of the Progress of the Geological Survey of the State of Virginia for the year 1839, by William B. 

 Rogers, Richmond, 1840. 



<■ Ibid,, 1840, Richmond, 1841. 



