MARCELLUS LIMESTONES AND THEIR FAUNAS 121 



i 



near the south line of Buffalo in the town of West Seneca. These 

 shafts penetrate the rock to a depth of 64 feet and transect a soil 

 covering of 26 feet. Of this rock section 49.6 feet are the black 

 highly bituminous shales of the lower part of the Marcellus and 

 beneath are 9.6 feet referred to the gray Onondaga limestone. 

 Parts of the black shale are somewhat calcareous and bear the 

 peculiar fauna at the base of the Marcellus section of the Livonia 

 salt shaft, referred to more fully on a subsequent page. In the 

 limestone beneath A g o n i a t i t e s expansus has been found, 

 associated with some small brachiopods which accompany it in its 

 occurence at Cherry Valley. 1 



From the data given above we conclude that in the region west 

 of Madison county to its extinction in Ontario county the Agonia- 

 tite limestone continuously approximates to the horizon of the 

 Onondaga limestone and that still farther westward its horizon 

 (the limestone itself having disappeared) actually coincides with 

 and merges into that of the Onondaga limestone. 



We now observe the following facts in its passage to its east- 

 ward extinction. 



Otsego county 2 



Cox's ravine, which begins f of a mile northwest of Cherry 

 Valley, shows the following section at base. 3 



Feet Inches 



1 Black fissile Marcellus shale with the usual fossils. 7 11 



Covered 7 4 



, 2 Heavy, black shale with L u n u 1 i c a r d i u m 



marcellense 2 8 



Covered 7 10 



3 Heavy, black shale with large concretions 6 5 



4 Limestone at 32 2 



i Prof. I. P. Bishop directed my attention to these excavations in October of this year and has 

 very kindly given me the rock section there exposed. Richard F. Morgan has at my suggestion 

 made a collection of the organisms there thrown out. I am under obligations to both of these 

 gentlemen. 



2 Dr Ruedemann has recently supplemented the data in our possession bearing on these sections 

 by a careful review of those in Otsego and Schoharie counties considered here. 



s The top of the Onondaga limestone is not clearly exposed in this section. Levels made from 

 exposures y z mile north of the railroad station indicate that this first outcrop of Marcellus shales 

 does not lie more than 7 to 10 feet above that limestone. 



