the variety and profusion of the fossils found in this group. 
The study and classification of all its different forms would 
give ample employment to an enterprising student for no 
small portion of his lifetime. 
If we overlook the fact that some of the sandstones of 
this group have been used for building purposes, and that 
the entire group furnishes a valuable addition to our soil, 
we can say that it has no economic importance. 
FOSSILS. 
Leltophylium Hallt is the most abundant of the cy- 
athophylloid corals, although, as already stated, there are 
many different species. Most of these are extremely 
abundant, and in some places constitute a large part of 
the rock, 
Other genera represented are: Zaphrentis, Cyathophyl- 
lum, Favosttes, Taentopora, Stictopora and Reptaria. 
Gasteropods.—If it 1s possible for any family to be 
more abundant than the corals, we must reserve that place 
of honor for the gasteropods. Many of the layers are just 
filled with Pleurotomaria, and with a little labor almost 
any number of them may be secured. 
Pleurotomaria sulcomarginata is the most abundant. 
It can be distinguished from all the others by the two dis- 
tinct revolving carina of each volution, which are crossed 
by numerous well marked striae. This species is said to 
be more abundant at Pratt’s Falls and Delphi in our 
county than at any other locality in the State. 
P. rotalia, Although this species is quite similar to 
the preceding, it can be distinguished from it by its shorter 
spire and more convex volutions, which are less distinctly 
marked by striae. Itis abundant in the harder layers at 
Pratt’s Falls, the preceding being more common in the 
softer. 
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