CARBONIFEROUS SYSTEM. 287 
At this point the conglomerate was not seen in situ, though numerous fragments were found 
upon the slope of the hill. 
The following is a section showing a similar structure in a block of conglomerate in the 
“ Rock city,” south of Ellicottville. 
134. 
Concretions and seams of iron ore. 
In many places this rock is traversed with seams of iron ore, which often stand out from the 
surface of the blocks, having resisted the influence of the weather which destroys the mass. 
These seams are sometimes in right lines ; at other times, undulating ; and rarely, if ever, in 
the direction of the lines of deposition. They are evidently segregations from the mass, and 
the irregular and undulating direction is due to accretionary force. In some instances, nodules 
of hydrate of iron have been found; at other times, the folded seams or laminae enclose a 
mass of sand, which has apparently resisted the formation of a solid concretion of iron ore. 
135. 
