CANANDAIGUA AND NAPLES QUADRANGLES 



31 



all the ravines already mentioned and in the Hamilton gully, Mill 

 gull and Jason gull in the valley of Honeoye lake. 



Cashaqua shale 



This name was introduced by Professor Hall for the characteris- 

 tic olive gray shales with occasional flags and sandstone as devel- 

 oped along the Cashaqua creek, a confluent of the Genesee river. 

 As these beds are continuous from that point eastward to the area 

 under consideration the term is completely applicable here. 

 In this area this mass of shales attains a thickness of about 230 

 feet, and is mostly bluish gray and olive shale with a few thin dark 

 layers and with two bands of thin sandstone and numerous flags 

 in the lower part. Calcareous concretions and discontinuous con- 

 cretionary layers occur in the upper part. As a whole the deposit 

 in Ontario county is more arenaceous and less calcareous than 

 that in the Genesee river section. In the lower 75 feet the more 

 sandy beds are rarely fossiliferous, showing occasional lignites and 

 frequently the object termed F u c o i d e s graphicus. At 

 about the middle of the series the shales become softer, and here 

 the characteristic fauna of these Portage rocks is typically devel- 

 oped with numerous goniatites, Bactrites and lamellibranchs of 

 the genera Buchiola, Lunulicardium, Ontaria etc. The character 

 of this fauna is referred to in a subsequent paragraph. Above 

 these more highly fossiliferous beds is a band of compact sand- 

 stone and hard shales which is succeeded by 57 feet of soft, blue 

 and olive clay shales, characterized by nodular structure due to 

 irregular concretions of lime carbonate of small size. Six feet 

 above the sandstone is a singular concretionary limestone which 

 is continuous in character, attains a thickness of about 6 inches 

 and is a mass of red and greenish kramenzel abounding in gonia- 

 tites and Orthoceras. This layer is so distinctive, both on account 

 of its color, its contents and its composition that it is here desig- 

 nated as the 



Parrish limestone. It appears first on the western boundary of 

 the Naples valley and is continuous from there eastward as far 

 as Big stream and Glen Eldredge on Seneca lake. Its place in 



