ECHINODERIIATA. 
The crinoidea, at least one family of them, are said to 
be especially partial to New York State. Not only is this 
true in regard to the vast number of crinoids found, but 
also in regard to the size which many of them have at- 
tained. In our county crinoid stems are the only parts 
found. These, however, grew to be quite large, speci- 
mens half an inch in diameter being common, while those 
an inch in diameter are not rare. Their length also is 
remarkable. It is notastrange thing tosee them extend- 
ing across the entire breadth of some of our stone side- 
walks, often several feet in length. Since these crinoids 
are not found entire, but the stems only, there has been 
some doubt as exactly where to classify them. In the 
early State reports they are called Axcinztus Lavis. Some 
of these stems are very beautiful, having a radiating struct- 
ure extending from a central star, circle or polygon. 
Usually these stems are the same color as the limestone, 
but occasionally specimens are found having a very deli- 
cate pink color; the latter are, of course, the more highly 
prized. This variety is often found at Split Rock. 
GASTEROPODA. 
This family is well represented in the Corniferous 
Period, and is, no doubt, more abundant in that formation 
in our county than anywhere else. The particular layer 
that abounds in these specimens is an impure shaly mass 
overlying the Onondaga Limestone. It is well exposed 
at the Indian Reservation. In referring to this layer at 
the Reservation, State Geologist Hall says: ‘‘ This shale 
has probably afforded twenty times as many specimens (of 
Platyostoma turbimata) as all the other localities in the 
State.” Again, in commenting upon the great variety in 
genera and species found at this place, he says: ‘‘It would 
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