346 MESOZOR' FLORAS OF UNITFD STATES. 



The paper l)y XuttuU from wliich Mr. Taylor takes the above state- 

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

 PhihKlelphia. \o\ 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 tlie 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 

 l)y Prof. W. B. Rogers, State geologist of Mrginia, 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 theu- 

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

 the vicinity of Fredericksburg and l)elow Richmond and Petersburg, 

 mentioning the Aquia Creek cjuarries. 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- 

 mation 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 formation" 

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

 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 afteiwards 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, aufl are younger than, the coal basins of Henrico, 

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



" Report of the Geological Reconnaissance of the State of Virginia, made under the appointment of the 

 board of puhlir works, by William B. Rogers, Philiiilclpliia. 18.36, p. fil. 



It sbmild be stated tlmt tliis and nil tlie subs('i|iicnt reports of I'rofessor Rogers arc lili'ially n'|)riiiti'il in a 

 much more accessible form in the volume entitled, A Reprint of Annual Reports and ullicr I'npers, on the 

 Geology of the Virginias, by the late William BartDii Rogei's, New York, 1.SS4. 



'' Report of the Progress of the Geological Survey of the .State of \'irginia for the year 1839, by William B. 

 Rogers, Richmond, 1840. 



<■ Ibid., 1840, Richmond, 1841. 



