82 The American Geologist. August, 1903. 
The Moscow Shale. The Encrinal Limestone. The Lnd- 
lowvillc, etc.. Shales. But these divisions cannot be recognized 
at any considerable distance from bis typical locality. 
The Tally Limestone. — Above the topmost layers of tbe true 
Hamilton in New York — tbe Moscow shales — and occupying 
only a small area in the region of tbe present "finger-lakes," is 
found a remarkable bed of impure calcareous material, which 
received from professor Hall the name of the Tully limestone. 
Seldom exceeding ten feet in thickness, it is yet quite persist- 
ent over an area of perhaps fifty miles in diameter, separating 
the Hamilton strata below from the Genesee shale above it. 
This insignificant band would itself require little mention were 
it not for some interesting palseontological facts connected with 
it and certain important discussions to which the facts have 
given rise. 
All attempts to identify the Tully limestone beyond tbe small 
area around tbe "finger-lakes" has failed. Professor X. H. 
Winchell thought that he had discovered it in Ohio, and in his 
report on Delaware county he says : 
"The shaly limestone near the base of the Olentangy shale is im- 
mediately underlain by a very hard crystalline limestone which is some- 
times black, but frequently purplish, containing pyrites in abundance, 
but very few evident fossils. — In the report on Marion county it has 
been referred to the Hamilton, where it probably belongs, and seems to 
represent the Tully limestone of Xew York."* 
But Dr. Newberry comments on the above passage thus in 
a foot-note : 
"The Tully limestone of Prof. Winchell's sections is certainly Ham- 
ilton, as I have obtained from it Tropidoleptus carinatus, Pterinea 
ftabellum, Nyassa arguta, Spirifer mucronata, etc. That it is the equiv- 
alent of the Tully limestone is not indicated by any evidence yet ob- 
tained." 
Again, in bis report on Montour county, Penna., professor 
White, speaking doubtfully, says: 
"The Tully limestone is identified in this region only by its appear- 
ance, its fossils being the common Hamilton forms. But as the beds 
immediately above it are certainly the representatives of the Genesee 
there can be no impropriety in referring it to the Tully horizon." 
The wisdom of professor White's caution can scarcely be 
doubted on examining his list of fossils. On a later page | _> 
he says : 
* Geo!, of Ohio. vol. ii, p. 288, 
