Comparatire Taxonomir TttlJ, 



Clark and Bibbins, 

 1897. 



W. B. Rogers, 

 1841. 



J. C. Booth, 

 1841. 



P. T. Tyson, 

 1862. 



G. H. Cook, 

 1868. 



W.B.Rogers, 

 1879. 



Ch. E. Hall, 

 1881. 



R. P. Whitfield, 

 1885. 



W J McGee, 

 1888. 



P. R. Uhler, 



1SSS. 



W.M. Fontaine, 

 1889. 



N. H. Darton, 



.1. s. Newberry, 

 1895. 



1.. k Ward, 

 1895. 



O.C. Marsh, 

 1898. 





Raeitan. 









Plastic clays 



(Woodbridge 



and Amboy 



clays). 







Raritan clays. 





Alternate 

 clay-sands. 



Albirupean. 





Magothy. 



Amboy clays. 



[gland series, 

 iUbirupean 



scries. 





a 



| 



i 



Patapsco. 





Red clay for- 

 mation 

 (Upper Sec- 

 ondary in 

 part). 









Wealdenclay. 





Upper or clay 

 member. 





Upper or clay 

 member. 







[ron ore 



series. 









Upper 

 Secondary. 





Upper Oolite 

 (iron ore 

 clays). 





Juiusso- 



Cretaceous. 







Potomac. 



Baltimorean. 



Potomac 



or 

 Younger 

 Mesozoic. 



Potom AC 





Aquia Creek 

 series. 



Mt. Vernon 

 scries. 



Potomac 



Jurassic 

 Formation 





ARUNDEL. 

















(Varicolored 

 clays). 





(Variegated 

 clays). 











I 





























Rappahan- 

 nock series. 







Patuxent. 







Lower Oolite 



(sands and 



clays). 











Lower or 

 sandstone 

 member. 





Lower or 

 sandstone 

 member. 







James River 

 series. 



1 



