204 JOURNAL OF THE PLYMOUTH INSTITUTION. 
THE PALAONTOLOGY OF PLYMOUTH. 
BY MR. R. N. WORTH, F.G.S. 
(Read October 18th, 1877.) 
Two years ago I had the honour of lecturing to the members of 
this Society on the ‘‘ Geology of Plymouth” and the surrounding 
district. I have now to offer a few notes upon the local pale- 
ontology—the extinct natural history of the district, the records of 
which are embodied in our rocks, or entombed within our caverns. 
As the local geology of this, like other parts of Devon which le 
within the limits of the commonly accepted Devonian system, 
opens up subjects of wide scientific controversy, which we cannot 
yet hope to settle conclusively ; so the local paleontology embraces 
many points of special interest upon which we are not adequately 
informed, while it requires to be worked at considerably before we 
can regard it in anything like its full extent. Therefore although 
the known paleontology of Plymouth is rich and varied, I take it 
up now simply in a tentative spirit. Before we can be said to 
have had a full and complete review of the ‘‘ Geology of Plymouth”’ 
it will be necessary that some remarks should be made upon the 
local petrology. This was a branch of the subject particularly 
handled by our late revered member Mr. John Prideaux, while 
another of the honoured fathers of this Society, the Rev. Richard 
Hennah, dealt specially with our paleontology. Petrology now, 
however, occupies a far different position to that which it did 
forty years ago; and upon some future occasion I hope to be enabled 
to offer some remarks on that topic also, and to make more com- 
plete the present cursory paleontological review. 
Before I proceed, however, let me supply an accidental omission 
in my paper on the “Geology of Plymouth” by mentioning the 
existence of a small Triassic outlier between Cawsand and Pickle- 
combe—a mass of conglomerate resembling the Triassic conglo- 
