REPORT OF THE STATE PALEONTOLOGIST 1902 1009 



The Wiscoy shales are also exposed in Scotts ravine 2 miles 

 northeast of Fillmore and in several other ravines on the east 

 side of the valley opposite Rossburg. 



Naylor's quarry near the Erie Railroad station at Castile 

 shows a small section in the Wiscoy shales in which 

 Manticoceras rhy nj3 hostoma is common at one hori- 

 zon in the soft sandy shale. 



Toward the east the Wiscoy shales are more arenaceous, and 

 the horizon is one of laminated or flaggy olive sandstones in 

 which Chemung brachiopods are abundant. 



Long Beards riffs sandstone. There are no rock exposures 

 along the river between the Genesee Bluestone Co.'s quarries 

 and Long Beards riffs, y 2 mile south of Fillmore, a distance 

 of about 8 miles. 



At this point an uneven layer of hard calcareous sandstone 

 makes a low cascade in the river and is exposed on both sides 

 of the channel. 



An escarpment on the east side of the riffs shows 10 feet 

 of shales and flags below the principal layer, and 3.5 feet of 

 shales with a few even layers of sandstone above it. 



This heavy layer and another 4 inches thick 25 feet higher 

 contain Chemung brachiopods abundantly. 



This horizon is the lowest in which Chemung brachiopods 

 were found in place in the Genesee river section. 



Estimates based on such measurements as could be made, 

 show it to be about 167 feet above the top of the " Portage 

 sandstones " as exposed at Portageville. 



Resume 



The Portage group, as exposed in the gorge of the Genesee 

 river, which is the type section, includes between the top of the 

 shales bearing a distinctively Genesee fauna at the mouth of 

 the gorge and the top of the Wiscoy shales at Long Beards 

 riffs, 1207 feet of strata. 



Marked changes in the character of the sedimentation make 

 the following subdivisions of these beds recognizable, beginning 

 at the base of the section: 



