REPORT OF THE STATE PALEONTOLOGIST I903 179 



GENERALIZED SECTION AT TRILOBITE MOUNTAIN^ 



Feet Feet 

 Onondaga limestone (max. exposure) 235 ± 



Esopus grit 55o± 



Oriskany limestone t8o± 



Upper or Spirifer muchisoni zone 15^''' 



Lower or Dalmanites dentatiis zone 30± 



Port Ewen beds 20O± 



Becraft limestone 16 



New Scotland beds i7o± 



Upper or Spirifer cyclopterus zone 125 ± 



Lower 45 ± 



Coeymans limestone 42 



Upper or Cherty 11 



Middle or Chert free 28 



Lower or Favosites bed 3 



Manlius limestone (max. exposure) 41 



GENERAL DESCRIPTION OF HORIZONS 



Manlius limestone 



The Manlius limestone is exposed in six of the sections. It is a 

 very compact, dark blue or almost black rock, containing many black 

 shale seams. All the beds give evidence of more or less disturbance, 

 the thin shale layers being at times minutely and irregularly crum- 

 pled, while the thicker beds, incapable of this minute displacement, 

 present rather the appearance of little hillocks. Many calcite veins 

 penetrate the rock mass, specially separating shale seams from the 

 limestone. Chert occurs as scattered nodules but is not nearly as 

 abundant as in tlie higher formations ; it seldom gives any evidence 

 of the presence of fossils, and even when deeply weathered it shows 

 little else than a few crinoid joints. 



The greatest thickness, 41 feet, is exposed in section F. The other 

 sections give exposures varying in thickness from 2 to 31 feet. 



Fossils are comparatively rare except in very restricted beds. The 

 most characteristic and abundant species are Spirifer vanux- 



^See fig. 3. 



