No. 50.] 379 
the Erie canal, and were it not for the deep valley of excavation whose 
course is north and south, they would merely exhibit a superficial north- 
ern outcrop. They all disappear in the order enumerated, one pass- 
ing under another, and finally the whole are covered in their progress 
south by the shales and the sandstones which succeed to them, the for- 
mer sinking deeper and deeper, as newer or higher rocks in the series 
appear, the whole series or class ending only with the coal of Pennsyl- 
vania. The characteristic fossil of the Seneca limestone is the Stro- 
phomena lineata. The rock in some localities swarm with them ; they 
are more abundant to the west of Oneida creek, than to the east of that 
creek. 
Marcellus shales. The colour of these shales are of deep black from 
carbon. In some localities from the accumulation of its colouring mat- 
ter it appears as well characterized coal, exciting high expectations of 
abundance by excavation and in every attempt disappointing its explo- 
rers. From place to place along the long line of its extension east and 
west, pits may be seen which were dug for coal. 
These shales contain in some localities layers of limestone separated 
by shale, in others the layers are interrupted from diminution of material 
appearing elsewhere as Septaria, and finally disappearing altogether. 
In Oneida Creek and near Manlius square, there are two layers of lime- 
stone which abound in Fossils consisting chiefly of Goniatites and Ortho- 
cera and confined to this rock. At Cherry Valley, the shales are abun- 
dant in fucoides retaining their carbonaceous material, and it is proba- 
ble that the shales owe their carbon to vegetation of their kind. At 
Cherry- Valley the shales are interposed or separated by irregular layers 
of limestone, their surfaces covered with knobs, the result of irregular 
accretion. 
Upper shales of Marcellus. These are less highly coloured than 
the lower ones. They contain no fossils for one or two hundred feet, 
or more where thickest. They are disposed to break into small frag- 
ments, flat and showing a tendency to a peculiar concretionary struc- 
ture, exhibiting slight stains from iron rust, owing to minute particles 
of pyrites. The whole of this mass has been formed from mud, whose 
particles were of great tenuity. This mass is thickest to the west, 
thinning out to the east. At the village of Marcellus, Onondaga county, 
both these shales may be seen to the greatest advantage. Going from 
