354 Review of the New York Geological Reports. 



Art. XII. — Review of the New York Geological Reports. 



(Continued from Vol. xlvi, p. 157.) 



New York System. — In the first part of the review of the New 

 York Reports, it has been shewn that the older palaeozoic or pro- 

 tozoic rocks of Marchison form the characteristic geological fea- 

 tures of the state of New York, and hence they are designated the 

 New York system by the state geologists. These, therefore, es- 

 pecially demand, and will now receive, a more detailed notice. 



As a vast multitude of facts have .been accumulated by the 

 able individuals who have prosecuted this survey during the last 

 seven years, we can of course only cull from these, those forma- 

 tions which, either from their geographical extent, economical 

 importance, or peculiar geological interest, will occupy most of 

 our attention, while the minor, partial formations can receive on- 

 ly a passing glance. 



The following hst presents, in a tabular form, the divisions and 

 subdivisions of all the rocks embraced in the New York system : 



Systematic subdivisions, founded upon the fossil and lithological 

 characters. 



1. Potsdam sandstone. 



2. Calciferous sandrock. 



3. Black River limestone group, embracing the Chazy 

 and Birdseye. 



4. Trenton limestone. 



5. Utica slate. 



6. Hudson River group. 



7. Grey sandstone. 



8. Oneida or Shawangunk conglomerate. 



9. Medina group. 



10. Clinton group. 



11. Niagara group, including shale and limestone. 

 '12. Onondaga-salt group. 



13. W^ater-lime group. 



14. Pentamerus limestone. 



15. Delthyris shaly limestone. 



16. Encrinal limestone. 



17. Upper Pentamerus limestone. 



18. Oriskany sandstone. 



19. Cauda-galli grit. 



20. Schoharie grit. 



21. Onondaga limestone. 



22. Corniferous limestone. 

 '23. Marcellus slate. 



C Moscow shales. 

 24. Hamilton group, < Encrinal limestone. 

 f Ludlovvville shales. 



Geographical subdivis- 

 ions. 



Champlain Division. < 



Ontario Division. < 



Heldereerg Series. < 



Erie Division. 



25. Tully limestone. 



26. Genesee slate. 



27. Portage or Nunda 



28. Chemung group. 



;roup, 



' Portage sandstone. 

 ' Gardeau flagstones. 

 Cashaqua shale. 



