THE HAMILTON ASSOCIATION. 7 
in or about this city yet undescribed, like the graptolites. Many of 
the Polyzoa have frequently been figured from mere fragments. 
“Their study is thus attended,” remarks the late Professor H. A. 
Nicholson in “ Palzeontology of Ontario,” ‘‘ with special difficulty,” 
Since there is no class of organisms requiring greater skill and 
patience in their interpretation, the learned Doctor made the 
Bryozoans a particular study. He was specially selected by the 
Director-General of the Ohio Geological Survey to report on the 
Corals and Polyzoans of the State, and his work proved that no 
better selection could have been made by Dr. Newberry. He and 
his friend, Dr. G. J. Hind, discovered in the Devonian rocks of the 
Province quite a number of Bryozoans new to science. They are 
so accurately drawn that I cannot see how any mistake can possibly 
arise regarding them. But, unfortunately, we did not hear of the 
Professors’ arrival until they had left Hamilton, and no person 
pointed out to them the places where the most interesting fossils 
were to be obtained. Few collectors would ever imagine that 
ploughed fields on the Niagara Escarpment were likely hunting 
grounds for sponges and various other organisms of the Silurian 
Age. Nevertheless, it so happened here that when the upper chert 
beds were removed, ground into muddy sediment in fact (which any 
one may notice on the lower clay resting on the glaciated layers) 
some of the harder and more flinty nodules successfully resisted the 
grinding process, and are now found resting on the surface of the 
glaciated layers. It is quite true that in some instances the plough 
has turned up the upper beds, near the brow of the Escarpment 
where the surface soil is shallow ; but such was a rare occurrence. 
The flint (or chert flake fossils), except occasionally an odd 
one, are confined to two fields close to the corporation drains, 
reclaimed swamps, and to a low-lying part of a field in rear of the 
reservoir. The frost in winter generally exposes the interior, if it 
holds any organic remains, splitting it into thinner slabs. 
I am inclined to think, instead of being washed down from 
higher ground into the hollows, the chert flakes were deposited by a 
local retreating glacier. The higher ground, near the Corporation 
drain, is the base of the new Barton, Niagara beds, hard shales, etc., 
not like the new chert ones. 
Barraude asserted, many years ago, that the graptolites in 
Europe attained their chief development at the time when the upper 
