Prossek — Hamilton and Chemung Series. 



119 



1. Jjumdica/i'diurn fragile^ Hall. (it) 



2. IAoptei-ia sp. (it) 



3. Crinoid stems. 



A single specimen of IAorhynchus mesacostalis, Hall, was found, but it 

 was on a loose piece of stone in the quarry, and may have come from farther 

 up the hillside. On the highway below the quarry are black, argillaceous 

 shales of the Genesee, and in the run below the road is the Tully limestone. 

 The thin sandstones which contain an occasional fossil, and the blue shales 

 that weather to an olive color, belong to the Sherburne formation. 



The clear stratigraphic succession of the rocks forming this section ; the 

 very fossiliferous shales with abundant Hamilton fossils in the lower part of 

 the run, belonging in the Hamilton formation ; followed by twenty-seven feet 

 of calcareous layers, part of which are impure massive limestones, referred to 

 the Tully ; succeeded by a black, argillaceous shale similar in all its litho- 

 logic characters to the Genesee ; capped finally by thin sandstones and blue 

 or olive shales, called the Sherburne, and which contain a few fossils, seem to 

 prove the correlation offered by the writer for the rocks of this region. The 

 stratigraphic order of the rocks just described is shown diagrammatically in 

 the accompanying section. 



XVIII A z . Gorge and falls in Pleasant brook at Upperville. The water 

 falls over about fifteen feet of coarse, blue, arenaceous shales, in which fossils 

 are common, particularly Spirifer granulosus (Con.), Hall and Clarke, and 

 some large Lamellibranchs. Some of the shales which contain many shells are 

 somewhat calcareous, and the outcrop extends along the bed and sides of the 

 brook for some distance below the falls. The rocks belong to the Hamilton 



formation, and the following species were collected : 



1. Spirifer audaculus (Con.), Hall and Clarke. (c) 



•2. Spirifer granulosus (Con.), Hall and Clarke, (c) 



3. Spirifer murronatus (Con.), Bill. (it) 



4. Curtina Hamiltonensi*. Hall. (c) 



5. Orthis Vanuxemi, Hall. (r) 



6. Chonetes mucronata, Hall. (rr) 



7. Pala-oneilo fecunda, Hall. (?) (rr) 



8. Palceoneilo emarginata (Con.), Hall. (rr) 



9. Modiomorpha eoncentrica (Con.), Hall. (rr) 



10. (rrammi/sia arcuata (Con.), Hall. (rr) 



11. Phacops ran a (Green), Hall. (r) 



12. BelUrophon crenistria, Hall. (?> (rr) 



