41 
nating white and blue concentric coats, with a geodetic cavity 
of quartz crystals forming the center of some of them. 
At the Green Lake west of Jamesville this formation occurs 
as a thin bed of black concretions, three inches thick, with a small 
quantity of yellow sand. The exposure described is just west of 
the lake and is not easily located, owing to the talus which cov- 
ers it at many points. 
The fossils are few and poorly preserved. Parts of the casts 
of Spirifera arenosus and Strophomena rhomboidalis were seen. 
At Britton’s quarries on the eastern ridge of Onondaga Val- 
ley, four miles southeast of Syracuse, the sandstone outcrops on 
the southern side of the quarry. It is of a rusty red color, twenty- 
one inches thick, with many dark, globular concretions. The 
rock is quite fossiliferous; the lower part in particular, seems to 
be made up of the casts of the various species. The rock is dis- 
integrating near the top and is darker in color. The overlying 
layer of Onondaga limestone contains some sandy nodules in the 
lower part. These nodules are quite often in contact with char- 
acteristic Corniferous Corals. 
At Hibbard’s quarry, one-half mile south of Britton’s, the 
Helderberg and Corniferous limestones are separated by a thin 
bed of rusty sandstone, five or six inches thick. The black con- 
cretions are also present. 
At Russell’s quarry, just south of Hibbard’s, the Oriskany is 
to be seen near the top of the eastern wall of the quarry, likewise 
the southern wall. The exposure, with six feet of Corniferous, 
passes beneath the over thrust Helderberg, at the line of fault 
which crosses the quarry at this point. It does not occur on the 
uplift farther south. The rock is about eight inches thick, the 
lower half being unconsolidated and including some thinly lamin- 
ated clay not thicker than paper. The upper part is harder and 
exhibits many shades of grey and black colors. Dark colored 
concretions and fragments of rock are included in it. Some sam- 
ples of the rock are decidedly calcareous. There are also a few 
white quartz pebbles as large as beans. A few fragments of fos- 
sils can be found here. 
The layer of underlying limestone is sandy in the upper part. 
