12 NEW YORK STATE MUSEUM 



A shallow cut of the Lehigh Valley Railroad 2 miles north of 

 Auburn shows Rondout waterlime and it is well exposed along and 

 near the New York Central Railroad east of Sennett. 



Fossils. The fauna of the Rondout waterlime in this region com- 

 prises but few species and they are very rare. Leperditia alta 

 Conrad and L. scalaris Jones occur and fragments of euryp- 

 terids are occasionally found. 



i 

 Manlius limestone 



This formation, formerly well known as Tentaculite limestone, is 

 'j'j feet thick at Manlius, Onondaga co., but it diminishes rapidly 

 toward the west and disappears in the vicinity of Seneca Falls. 



It is composed of a series of distinct layers of hard, dark blue lime- 

 stone from 2 to 5 feet thick, separated by thin partings of black 

 bituminous matter. Some of these layers are quite compact and the 

 lines of deposition are faint, but in others the rock has a straticulate 

 appearance due to an alternation of thin plates of dark bituminous 

 limestone and lighter colored impure limestone or waterlime. The 

 laminations are from ^ to 2 inches thick and exposure makes the 

 contrast more noticeable. 



The rock splits easily along the lines of deposition and breaks into 

 angular blocks making it valuable for building purposes and road 

 metal. 



It is exposed to the thickness of 18 feet 8 inches in the extreme 

 southern quarry on the east side of the Lehigh Valley Railroad a mile 

 south of Union Springs, where it is separated into five distinct 

 layers, with Onondaga limestone above, separated from it by a thin 

 uneven band of dark material representing the Oriskany sandstone. 



In the upper bed, 4 feet 5 inches thick, the rock is blue gray with 

 faint lines of deposition and few fossils. The next bed in descending 

 order is 5 feet 3 inches thick and contains Stromatopora 

 concentrica Hall abundantly, making the limestone somewhat 

 purer and harder than the adjacent layers. 



This stratum possesses the same condition eastward across Cayuga 

 and Onondaga counties and is well known as the upper Stromatopora 

 layer, a stratum of almost precisely the same appearance in the 

 Cobleskill limestone on this quadrangle and farther west being dis- 

 tinguished as the lower Stromatopora layer. 



The stratum next below, 3 feet i inch thick, contains the fossil 

 less abundantly and it is absent in the two lower tiers. 



