BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Vol. 28, pp. 945-958 DECEMBER 19, 1917 



PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



STEATIGEAPHIC EELATIONSHIPS OF THE TULLY LIME- 

 STONE AKD THE GENESEE SHALE IN 

 EASTERN NORTH AMERICA^ 



BY AMADEUS W. GRABAU 



{Presented before the Paleontological Society December 29, 1916) 



CONTENTS 



Page 



Character and distribution of the Tully limestone 945 



Relationship of the Tully limestone and Genesee shale \ 949 



Southward disappearance of the Tully limestone 951 



Origin of the Genesee shale 952 



The Tully fauna ; .*. 956 



Character and Distribution of the Tully Limestone 



In its type locality near Tully, in the central part of New York State, 

 the Tully limestone has a thickness of about 23% feet and rests conform- 

 ably on the Upper Hamilton (Moscow) shales. The contact between the 

 two is well shown in the cliff of Tinkers Falls, several miles east of Tully, 

 and appears to be an absolutely gradational one. This is shownT by the 

 fact that the somewhat sandy shales of the Upper Moscow gradually be- 

 come finer and more calcareous and beds of a more strongly limy char- 

 acter alternate with layers of more argillaceous material. Finally, the 

 lime entirely replaces the clay and the impure Tully limestone is devel- 

 oped. The contact is thus a transitional one, and the Tully must be re- 

 garded as marking the passage of sedimentation without break from the 

 Middle to the Upper Devonic. The faunas, too, partake of this transi- 

 tional character, as is shown by the fact that the majority of species found 

 in the Tully limestone are forms equally characteristic of the Upper Ham- 

 ilton (Moscow) shales of central New York, only a comparatively small 

 proportion being of types newlv added. 



Manuscript received by the Secretary of the Geological Society July 25, ]917. 



(945) 



