(29) 
I should be very glad if this, and many more of 
the productions of our rocks, could be carefully 
investigated ; as I am well persuaded, that numbers 
of them have never yet been described, or classed, 
in any publication. 
In the fragments of Limestone, raised from pits 
that were opened on the North side also of this 
hill, while the houses were building in Union-street, 
which leads from Stonehouse to Plymouth, I obtained 
’ several satisfactory specimens of Bzvalves and Madre- 
porites; and observed, that they were abundant in 
different parts of these rocks. And, in masses of 
blue, or grey Limestone, mixed with clay-slate, taken 
up from some wells that were sinking at the time, 
at the back of those houses, both on the North and 
South side, Madreporites, Trochites, and other relics 
were in considerable quantities. In one, if not in 
two instances, Pyrites was mixed with them; a sin- 
gular circumstance, and not unworthy of notice.— 
These are the only places, where I. have found Py, 
rites so blended with Animal Remains, throughout 
the whole distance, from the Plym to the Tamar. 
