238 
PALAEONTOLOGY OF NEW YORK. 
Orthoceras masculum, n. sp. 
PLATE LXXVIII B, PIG. 1. 
Shell large, straight. Transverse section circular. Tube very gradually 
expanding. Initial extremity unknown. 
Chamber of habitation not observed. Depth of air-chambers varying 
from ten to sixty-five mm.; their internal casts, in the specimen figured, 
show a crenulated or tuberculated band at the anterior portion of each. 
Septa irregular, generally very distant, straight and horizontal; concavity 
unknown. 
Position of the siphuncle not determined. Test removed from all 
observed specimens. 
The internal mould is essentially smooth, with the exception of the 
crenulated bands above mentioned. The chamber walls are flat, with the 
septal sutures but slightly impressed. The specimens are often covered 
with numerous individuals of a species of Spirorbis. 
One fragment having a diameter of eighty mm., and containing four 
air-chambers, measures 200 mm. in length. A similar specimen, with a 
diameter of nearly 100 mm. and seven air-chambers, has a length of 220 
mm. A smaller fragment with a diameter of the tube of sixty mm., and 
possessing nearly four air-chambers, has a length of 180 mm. Several large 
sections, referred to this species on account of their size, have a diameter of 
from 105 to 125 mm. 
This species is remarkable for the large size and very gradual enlargement 
of the tube, and the extreme variation in the depth of the chambers. These 
characters distinguish this form from any associated species, or any species 
now known in the Devonian period. 
Formation and localities. From the Schoharie grit, in the vicinity of Schoharie, 
and near Clarksville, Albany county, N. Y. 
