Pkosser — Hamilton and Chemung Series. 



179 



5. Modiomorplia concentrica (Con.), Hall. (it) 

 (5. Palceoneilo emarginata (Con.), Hall. (it) 



7. Mytilarca (PfatTwmiyUhbs) oviformis (Con.), Hall. (r) 



8. Orinoid segments and part of stems. (c) 



XX F*. On top of the hill, one and one-half miles northeast of Pitts- 

 field and near the township line between Pittsfield and Ednieston, are thin, 

 rather irregular arenaceous shales containing Hamilton fossils. The top of 

 the hill is barometrically 370 feet above the railroad at New Berlin, but it is 

 two and one-half miles northeast of the locality at which the top of the 

 Hamilton was found at an altitude of 135 feet above the railroad, and if the 

 dip remains seventy feet or more per mile it would bring the top of the 

 Hamilton near the summit of this hill. The nature of the rocks and fauna 

 seems to favor the above conclusion and shows that the entire hill is com- 

 posed of Hamilton rocks. Eighty feet below its summit are very coarse 

 shales grading into sandstones that form rather prominent ledges containing 

 an abundance of Hamilton fossils. Spirifer granulosus (Con.), Hall, is abun- 

 dant ; Tropidoleptus carinatus (Con.), Hall, common; Pleurotomaria ca/pil- 

 laria, Con., rare. A careful search would yield considerable numbers of 

 characteristic Hamilton species. 



For some distance along the first brook entering Wharton creek from the 

 east, one and one-half miles above Pittsfield, the fossiliferous Hamilton shales 

 are found. To the south on the hillside the shales and sandstones of the 

 Sherburne occur, while on the high hill to the south, 500 feet above the 

 Hamilton shales in the brook, are those containing the fossils of the Ithaca 

 formation. This exposure occurs on the high hill to the north of Ketchuni. 

 However, on account of the thick deposit of drift covering the rocks of the 

 divide between the Wharton and Butternut creeks, it is difficult to describe 

 very closely the geological formations of the region. 



Geology of Southern Otseoo County. 



The southern part of Otsego county is covered by rocks belonging to the 

 Hamilton, Sherburne, Ithaca and Oneonta formations. In tracing the line of 

 division between the Hamilton and Sherburne formations across this county, 

 the geology of its southern part was quite carefully studied and will now be 

 described. 



