Mr. Winch on the Eastern Part of Yorkshire. 555 
in structure, but in colour being black as jet. Seams of this fossil 
are suspected to exist between the strata of bituminous shale before 
mentioned. 
On the Yorkshire beach, common and jasper agates, together 
with resplendent felspar, are collected. These must be the products 
of the Northumberland and Scotch mountains, where amygdaloids 
and porphyries are the predominant rocks. 
Of the organic remains in this district, the first particularly worthy 
of notice are the tusks and teeth of the Siberian elephant or mam- 
moth, and which are not mineralized, but remain in their original 
state. Tusks supposed to belong to the same species of quadruped,, 
have been found on the coast near Scarborough. 
The mineralized skeletons of animals formerly supposed to be 
those of alligators, occur in the Whitby cliffs. One of these was 
noticed in the year 1758, by Capt. William Chapman, and his 
account is printed in the Philosophical Transactions, at p. 688, and 
that of Mr. Wooller, at p. 786, plate 9, fig. 5. From the vertebrse, 
which I had the opportunity to examine, I make no doubt but 
these bones belonged to the same species of animal as the one 
found in the lias between Lyme-Regis and Charmouth, on the 
Dorsetshire coast, and accurately described by Sir Everard Home, 
in the same publication, at p. 571, and pi. 17, 18, 19, 20, and since 
called by him Proteo-saurus. 
The following petrefactions in the alum-shale are also worthy of 
notice : 
Echinus vulgaris * . . Parkinson, vol. 3, tab. 2, fig. 3. 
Ammonites serratus . . Sowerby, tab. 24. 
... . . . armata . . Sow. tab. 95. 
heterophillus Sow. tab. 166. 
Nautilus lineatus . . . Sow. tab. 41. 
