REPORT OF THE STATE PALEONTOLOGIST 1001 621 



Cashaqua shale on the river section, 165 feet, or 314 feet higher 

 than it is on the Genesee river, thus showing an average east- 

 ward elevation or pitch of 10J feet a mile. 



The Cashaqua shale is abundantly exposed in a large number 

 of ravines that score the hillsides between Canandaigua lake 

 and the village of Naples. The beds are quite sandy, flags being 

 common and a few layers of sandstone reach a foot in thick- 

 ness. The upper part is more argillaceous and calcareous than 

 the lower, and it is also more fossiliferous, the characteristic 

 fossils of the group being quite common in the softer shales. 



The second black band, less than half as thick as in the Gen- 

 esee river section, but well defined and easily distinguished is 

 exposed in the same ravines, and also in the rock cut on Rhine 

 street, and at the foot of Hatch hill, opposite the village of 

 Naples, where it dips under the water of Naples creek at about 

 775' A.T. 



Abundantly exposed at the foot of Hatch hill, and in the 

 upper parts of the ravines at the north, but much better in the 

 Tannery gully, 1 mile south, and the Grimes gully ^ mile west of 

 the village, there are about 300 feet of shale and flags that cor- 

 respond very closely, both in structure and fossils, to the Lower 

 Gardeau beds as they appear in the escarpments between Smoky 

 hollow and the top of the upper Portage fall. The shales are 

 black, bluish or olive, in all varieties, and the sandstones light 

 bluish gray with different degrees of hardness. At some hori- 

 zons the j)roportion of arenaceous matter is very small, while 

 at others it is equal to the argillaceous. 



At the top of these beds, and about 600 feet above the Gen- 

 esee shale a series of sandstones, varying in thickness from an 

 inch to 8 feet, and separated from each other by thin shaly 

 partings, and aggregating about 50 feet thick, produce the third 

 falls in the Grimes gully, the High falls in the Tannery gully, 

 and prominent escarpments on the sides of Hatch hill and West 

 hill. They are known as the Grimes sandstones. Their most 

 southern exposure is on Olney brook at the waterworks reser- 

 voir 1J miles south of Naples, at the elevation of 975' to 1025' 



