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NEW YORK STATE MUSEUM 



the Green lake, 1^2 miles west and the White lake, 2 miles north- 

 east from Jamesville. They are also seen in the Onondaga valley 

 in the old quarry east of the cemetery, y 2 mile north of Dorwin's 

 Springs and in several other quarries and ledges on both sides be- 

 tween the north line of the quadrangle and the reservation quarry. 

 The rock thins out and disappears at Split Rock near the northwest 

 corner of this quadrangle but reappears farther west and is 17 feet, 

 9 inches thick in the Corrigan quarry on the Skaneateles outlet. 



Fossils abound, specially Stromatopora, Favosites and Leperditia; 

 S p i r i f e r cyclopter us, Leptocoelia, Leptostrophia 

 becki, Leptaena rhomboidalis, Meristella 

 1 a e v i s , Rhynchospira f o r m o s a , Tentaculit.es 

 elonga^us and a few other species have also been recognized 

 and these occur most abundantly in the upper part of the strata. 



Oriskany quartzite 



This formation is very variable in thickness, sometimes not more 

 than 4 inches and sometimes 6 to 7 feet. It is a light gray occa- 

 sionally pinkish granular quartzite. The basal part which is nodular 

 for a few inches, usually contains flattkh fragments of dark hy- 

 draulic limestone. In some of the localities the sand grains are 

 well cemented and the rock durable, at others it is friable and 

 weathers to a dark rusty brown. In the northeastern corner of this 

 area it composes the lower part of the layer 2 feet 3 inches thick, 

 the upper part of which is limestone into which the transition is very 

 gradual Near Jamesville it is 3 feet, 6 inches thick, dark colored 

 and friable and on the west side of the Onondaga valley opposite 

 Onondaga Castle, it is 5 or more feet thick, light colored and quite 

 durable. 



The rock is exposed in the ravines and north of the highway to 

 Manlius, 4 miles east of Jamesville, in the cliffs at the White lakes 

 and the Green lake, in the Alvord quarry south of Jamesville, in 

 the highway near the Reservation quarry and in ledges northward 

 on the east side to the jamesville road. On the west side opposite 

 Onondaga Castle it is shown in a prominent ledge near the highway 

 and extends for about V2 mile, the rock here being a clean sandstone. 

 Many loose blocks are scattered along the side of the valley north- 



