FORMATIONS OF DEVONIAN AGE. 97 
The Orbiculoidea jervensis Zone. 
The total thickness of the siliceous limestone beds which bear the 
Orbiculoidea jervensis fauna are nowhere entirely exposed. The beds, 
however, are probably not of great thickness, the estimate being twenty 
feet, but this may be too great. But few outcrops have been observed, 
and the fauna has been detected only at intervals from the New 
York State line to about Hainesville. Beyond this point the fauna 
is either not differentiated from the general Oriskany fauna or the 
beds are so heavily drift covered as to escape observation. 
Locality 2 A**—The only exposure of the Orbiculoidea jervensis 
beds detected in the Nearpass section is a very limited one on the 
Werden farm, just north of the Sanford Nearpass place, near a pri- 
vate road leading over the hill to the gravel pits. It was from here 
that the type specimens of Orbiculoidea jervensis were originally col- 
lected by Dr. Barrett. The following species have been identified 
from this locality: 
1. Orbiculoidea jervensis (Barrett). 
2. Chonetes hudsonica Clarke. 
3. Spirifer murchisoni Castel. 
4. Beachia suessana (Hall). 
Locality 7 A——An outcrop of this zone occurs in the first cross-road 
over the Wallpack ridge, south of the New York State line, about 
three miles from the line. The following species have been recognized 
from this point: 
1. Orbiculoidea jervensis (Barrett). 
2. Chonetes hudsonica Clarke. 
3. Spirifer murchisoni Castel. 
4. Actinopteria sp. undet. 
Locality 6 A——By far the best locality observed for collecting the 
fossils of the Orbiculoidea jervensis zone is along the edge of the 
woods just south of the second wagon road crossing the Wallpack 
ridge, about five miles from the New York State line. From this 
locality the following species have been identified : 
. Trachypora oriskania n. sp. 
. Fenestella? sp. undet. 
. Orbiculoidea jervensis (Barrett). 
. Stropheodonta magnifica Hall. 
. Orthothetes sp. undet. 
7 
Or HB OF Ww fF 
