THE EURYPTERIDA OF NEW YORK , 411 
EURYPTERIDS FROM THE NORMANSKILL SHALE OF NEW YORK 
After the foregoing discussion of the Frankfort shale eurypterids had 
been prepared our attention was directed by Professor G. H. Chadwick 
to similar remains which he had observed in the sandstones of the Broom 
street quarry at Catskill, N. Y. The only fossils heretofore known from 
the so called ‘‘ Hudson River beds’”’ about Catskill are the Normanskill 
graptolites, indicating horizons of Upper Chazy age,' and the presence of 
eurypterid remains in this early stage was a matter of so much interest as 
to justify a careful examination of the locality. 
The lithologic and faunal conditions at the Broom street quarry expo- 
sure were found to be a singularly complete duplication of those of the 
eurypterid-bearing exposures in the bluestone quarries at Schenectady. 
The Broom street quarry is also a bluestone quarry, the rock being mostly 
used in the crusher. The courses of ‘‘ bluestone’ (here an impure argil- 
laceous sandstone) are very compact, from 3 to 30 feet thick between 
the intercalations of black shales. There is distinct evidence of shallow- 
water conditions, one bed being conglomeritic and largely composed of 
pebbles, many of which appear to be mud pebbles; another beautifully 
exhibiting very regular, widely separated wave marks with winnows of 
commuinuted seaweeds and eurypterids in the troughs. 
Quite as in the bluestone quarries of the Schenectady beds, the surfaces 
of some of the sandstones are densely covered with rather poorly pre- 
served seaweeds and eurypterids. It was therefore natural to expect . 
that here too the black intercalated shales would contain better material 
‘In the body of this work the species from the Schenectady beds have been 
referred to the “Schenectady facies” of the Frankfort beds. Investigations since 
carried on by the junior author in the thick formation of sahdstones and shales in the 
lower Mohawk valley, hitherto referred by all authors to either the Hudson River 
shale or the Frankfort beds, have shown that the faunal differences which induced us 
to distinguish the beds as Schenectady facies are of such nature that the whole form- 
ation has to be placed within the middle and upper Trenton. It will therefore in a 
forthcoming bulletin be distinguished as the Schenectady formation. 
