386 Tne American Geologist. Juno, 1897 
affords no reason for assuming the presence of a strong tidal 
current. 
A constant and only slightly changing current produces an 
even bedding in the deposits, while beneath strong tidal cur- 
rents, owing to the strong flow during the incoming tide and 
its alternation with high-water and low- water quiet, in the 
ebbing tide, laj^ers that are obliquely laminated alternate with 
ordinary layers. The Utica shales and slates in this neigh- 
borhood are remarkably even-bedded and there are no traces 
of cross bedding noticeable.* It is possible that the lack of 
oblique lamination in the Utica shale is due to the greater 
depth in which that sediment was deposited, but then it would 
seem strange that an inconstant and irregular tidal current 
near the coast should have resulted in a constant, apparently 
regular current in water of a greater depth such as that de- 
positing the Utica shale most probabl^y W:is. Tidal currents 
further are, however strong they may become in certain places, 
f)nly local phenomena; their influence extends neither far into 
the open sea nor into the oceanic depths. The uniform litho- 
logical and faunistic cliaracter and wide extension of the 
Utica shale, however, show that it cannot be the result of lo- 
cal and irregular physical agents. Moreover, the fine grain, 
even bedding, and rich admixture of carbonaceous matter in- 
dicate that the shale is the result of a very slow and equal 
deposition, such as generally takes place onl}^ in the deepest 
l)art of the littoral region. It is the concurrent opinion of ge- 
ologists that the graptolite shales and slates, in general are 
stow, deep-water deposits. This opinion is founded on the 
wide horizontal and small vertical distribution of the grapto- 
lites and graptolite shales. Hall has already reached this 
eonelusion in his exhaustive study of the Quebec graptolites. 
A glance at the accompanying map will show that the 
shale in the localities where the parallel arrangement of the 
fossils has been observed, must have been deposited in consid- 
erable depths, for the outliers of Utica shale at Wellstown on 
*OV)liqae striation in the Trenton limestone has been observed east 
of the Hudson (cf. Report of State Geologist for 1893, p. 428) which is 
of interest as it probably points to the presenee of shallower water in 
that region during the Trenton epoch and. as during the Trenton and 
Uti'.'B epochs the sea stood at the same level, also to a shallow region in 
the Utica epoch. 
