BUFFALO SOCIETY OF NATURAE SCIENCES 



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projects from the lake cliff just north of the mouth of Silver 

 creek. This is unsatisfactory, however, as it is the only exposure 

 of this layer in the county. Luther (p. 1024 Rept State Pal. 

 1902) describes a black layer four feet above a gray nodular 

 layer and seems to consider this the top of the Angola. There 

 is really nothing to distinguish one from the other. If the 

 Angola and Hanover shales are in the horizon of the Hatch 

 shales of Canandaigua, this name should be retained. 



F. Houghton, Photo. 

 Fig. 21. Sandstone ledge in Angola shale, Griffin's Mills, Cazenovia creek. 



The type exposure of Angola shale is in the cliffs of Big 

 Sister creek from the cemetery at Angola to Pontiac. There are 

 numerous exposures along the south branch of Eighteen Mile 

 creek from the Erie railroad bridge to a point well beyond the 

 State Road, and in a small gully debouching into the creek just 

 above the Erie railroad. A fine exposure begins at the junction 

 of the two branches of Cazenovia creek and extends upward 

 beyond Griffin's Mills. The beds in detail may be seen in a small 

 gully running from the west into Cazenovia creek at the bridge 

 south of Jewettville. 



