EXPLANATION OF TABLE IV. 

 Pages 99 & 101. 



Are the same rocks as Table III, (divided and described by others of the 

 New York State Geologists,) in a descending series from 1 to 13 ; on the 

 top of which are two groups, viz., the Coal Measures and Old Red Sand- 

 stone or Catskill Group ; then at the bottom are placed the Volcanic, the 

 Primitive Slaty or Striated, and the Primitive Crystalline, with the 

 Granite, &c. at its base. 



