LtTTHEK — PORTA* i B Sa NDSTON ES. 



'2'M\ 



exposure and its stratigraphic position can not be ascertained with precision. 

 •It is, however, not far from one hundred feet above the top of the third falls 

 sandstones. The layer is a compact sandstone, five inches thick, and contains 

 the following fossils: 



Dicfiyophyton tuberosu ni. 



Hystram-nthitx. 



Spirifer ))ie*<(<mtalix. 



_ Ytrijpn hystrioB. 



Prodtwtella speciosa. 



AiiibocuJia nmhonata var. grega/ria. 



Crinoid stems and heads, sp. und. 



This is clearly a Chemung fauna. About twenty feet higher in this 

 exposure a sandy layer contains Productella xpeciosa quite abundantly, and 

 forty-two feet above the lower fossiliferous layer there occurs a bed of plant 

 remains, in which I>. tuberosum and two or three other species of fossil 

 sponges are common. Other Chemung fossils are also found here. 



On the road leading from Naples village to West Hollow, near the resi- 

 dence of Charles S. Sutton, one of the thin sandstones of this horizon exposed 

 at the roadside contains Orthis Tioga, Liorltynchus mesacostalis, Production 

 spinuMcosta, AmboGcelia umbonata^ Atrypa n j ti<'idaris and sections of crinoid 

 columns. 



In a layer in the west branch of the Tannery gully, opposite M. Hatch's 

 house, Atrypa reticularis, Ortlwthetes Chemungensis, Amboccelia umbonata, 

 and a mass of crinoid plates and segments occur. This horizon is a little 

 higher than the others mentioned. 



Above these fossiliferous layers, others occur at frequent intervals, in 

 which the number of individuals and of species, which nearly or quite all 

 belong to the ordinary lower Chemung fauna, is much increased, sometimes 

 producing more or less persistent calcareous layers. The sandstones also 

 become coarser and lighter colored. 



From the foregoing it will be seen that the heavy sandstones at the top 

 of, and above the third falls in Crimes gully are the " Portage sandstones," 

 and are the upper and most southerly division of the Portage- group. They 

 are here about fifty feet thick, including the interstratified shales, and from 

 599 t<> 650 feet above the bottom of the lower black band. 



Toward the east from Naples, the line of outcrop of these sandstones is 

 easily followed around the head of Italy hollow, thence with a northerly bend 

 over Italy hill, and then south above Keuka lake, crossing the valley about 



