l8 NEW YORK STATE MUSEUM 



west to Hemlock lake; on Conesus lake in the ravines between 

 Old Orchard point and McPherson point, on the east side, and 

 between Eagle point and Long point on the west side. 



Fossils are rare in the West River beds, A few individuals of 

 the following species occur: 



Bactrites aciculum (Hall) 

 Gephyroceras sp.f 

 Pleurotomaria rugulata Hall 

 Buchiola retrostriata v. Buck 

 Pterochaenia fragilis {Hall) 

 Lunulicardium curtum Hall 

 Panenka sp. 



Lingula spatulata Vanuxem 

 Orbiculoidea lodensis Vanuxem 

 Melocrinus clarkei Hall 



MIDDLESEX BLACK SHALE 



A bed of black shale similar in appearance to the Genesee beds, 

 succeeds the West River shales to the thickness of 30 to 35 feet. 

 As the transition to the adjacent formations is gradual both above 

 and below, the assigned thickness is somewhat arbitrary. It may 

 be recognized beneath the lighter Cashaqua shale as far east as 

 Cayuga county, where it ceases to be separable from the West 

 River shale. Toward the west it is more distinctly differentiated 

 from the adjacent formations and on the shore of Lake Erie it is 

 a homogeneous band of black slaty shale six feet thick. 



This formation is exposed in the ravines in the Honeoye Lake 

 valley and in the region two miles south of Richmond Mills. It 

 is finely displayed on the road one-half mile southeast of Hemlock 

 and in the ravine at Glenville. It also appears in all of the ravines 

 on both sides of Conesus lake in the vicinity of McPherson point. 



Fossils are exceedingly rare in the Middlesex shale. The follow- 

 ing occur: 



Plant remains 



Fish remains 



Conodonts 



Sandbergeroceras syngonum Clarke 



Ontaria suborbicularis (Hall) 



