ORISKANY FAUNA OF BECRAFT MOUNTAIN 11 



10 Oriskanian. The Oriskany formation varies considerably in the chai acter of 

 its sediment. Its calcareous facies is highly developed in eastern New York, while 

 the more silicious sediment excludes all others in the central part of the state. The 

 fauna of the Oriskany from its lowest beds, as at Camden Tenn., to its highest beds, 

 as in the province of Ontario, shows progress in differentiation, but it is not yet 

 practicable to subdivide the New York development of the fauna. 



11 Ulsteriaii (new). From the outcrops of all the members in Ulster county, 

 N. Y. 



12 Erian. The Erie division comprised the formations from the top of the 

 Onondaga limestone to the top of the Chemung. We propose to save the term to 

 the New York nomenclature by reviving it with a restricted meaning. 



13 Senecan (new). In Senesa county and along the shores of Seneca lake are 

 excellent exposures of these beds. 



14 Ch'autauquan (new). From exposures in Chautauqua county, N. Y. 



15 Beekmantown limestone (new). The Calciferous sandrock of Eaton and authors 

 generally. This formation took its original name from sections in the Mohawk valley, 

 where the rocks are without fossils. At Beekmantown N. Y., the normal fauna is finely 

 developed and the rock section essentially complete. 



16 Lowville limestone (new); instead of Birdseye limestone of common use. 

 Lowville is a town in Lewis county, N. Y., where these beds are well exposed. 



17 Hudson river beds. It is becoming increasingly evident that the great mass of 

 shale in the Mohawk and Hudson river valleys which was designated at an early date by 

 this term is resolvable into horizons extending from the middle Trenton to and including 

 the Lorraine beds. At present it seems unlikely that, when this determination of horizons 

 has been carried through the series, any part will remain to which the original term can 

 be applied by virtue of its distinctive fauna, though it may still serve to designate a 

 facies of the formations mentioned. 



IS Rondout waterlime (new). From the fine development of these beds in the 

 extensive cement quarries at and near "Rondout N. Y. 



19 Manlius limestone. Tentaculite limestone of Gebhard, Mather and later writers. 

 The name here used was introduced by Vanuxem and is entitled to first consideration. 

 Manlius is the place of typical exposure in Onondaga county, N. Y. 



20 Coeymans limestone (new); and 



21 New Scotland beds (new). These terms designate respectively the Lower 

 Peritamerus (Helderberg and Pentamerus limestones of the New York geologists) and 

 the L'atskill or Dalthyris shaly limestones. Coeymans and New Scotland are adjacent 

 towns in Albany county, N. Y., through which runs the Helderberg escarpment, affording 

 the finest exposures of these formations. 



