Association of American Geologists and Naturalists. 155 



Our Primal series embraces the four great rocks between the base 

 of the Palaeozoic strata and the base of the first limestone, the calcife- 

 rous sandstone of New York. Of these the primal white sandstone, 

 would seem to be the only formation existing in New York, or accor- 

 ding to Owen, on the northwestern margin of the basin in the western 

 states. 



The Matinal series includes all the strata from the horizon of the 

 base of the calciferous sandstone, to that which marks the top of the 

 Hudson River slate in New York, and the top of the blue limestone of 

 the western states. This series in southwestern Virginia and East Ten- 

 nessee, embraces a thick and important middle group consisting of 

 three formations, not extending northeast of the New River, and only 

 imperfectly represented in some portions of the westeraTstat.es. 



The Levant series includes all the formations between the horizon 

 terminating the Matinal rocks and one running through the top of the 

 water lime formation of New York, the top of the non-fossiliferous 

 a nd " pitted rock" of Lake Huron, and through a plain low in the cliff 

 hmestofle of the western states* It takes in, therefore, the Medina, 

 Winton, Niagara and Onondaga salt groups, and water lime of the New 

 York survey. 



Jne Premedidial series embraces the strata between the top of the 

 mt€r tone and the top of the Oriskany sandstone of New York, and 

 deludes, therefore, the Pentamerus and Cat skill shaly limestones of 



1 State as its oldest formation, and the Oriskany Sandstone as its 

 ^west ; and besides these, a middle formation not there seen but well 

 oped * n Pennsylvania, with characteristic fossils. 



* he Medidial series ranks in it all the strata between the top of the 



Oriska 



New York, or the black bituminous slate of Ohio, Indiana, Kentucky 

 * nd Midd 'e Tennessee. It, therefore, includes the Schoharie grit and 

 nondaga and corniferous limestones of New York, and the upper 

 vision of the cliff limestone of the west. 



The Postmedidial series embraces that very natural assemblage of 



Nations commencing with the black slate just named, and crossing 



*** the horizon which marks the base of the Catskill red sandstone. 



Contains, therefore, for New York the Marcellus shades, the Hamil- 



ton group, the Tully limestone, the Genesee slate, the Portage group 



and the Chemung group, and for the west all the strata between the 



t0 P of the cliff limestone and the bottom of the carboniferous lime- 

 stone. 



n y or Premedidial sandstone and the Marcellus black slate of 



