145 
verian Museum, and which had frequently been with me an object 
of admiration, seems to exhibit nearly the complete form of the shells 
of this genus. The particular figure of this fossil had been, by most 
of its observers, attributed to some changes which it had undergone 
whilst in a soft mineralized state ; but I had been always satisfied of 
its existing in its original shape, from reflecting on the improbability 
of its spiral turns having been unfolded without fracture : a circum- 
stance, indeed, which an examination of the specimen renders at once 
evident. This curious fossil, which is formed of a blueish clay, was 
found, as appears by a label, which is attached to it, in Shotover Hill, 
near Oxford. 
LXXX. Scaphites. A fossil concamerated shell, commencing with 
spiral turns ; the last of which, after being elongated, is reflected 
towards the spiral part. 
I have ventured to form the present genus for the reception of the 
very rare and interesting fossil, Plate X. Fig. 10, from Dorsetshire, 
there being no genus in which it could be placed. 
This fossil is in a very excellent state of preservation : the nacre is 
visible on some parts of it, and in others the foliaceous terminations of 
the chambers may be discovered. At the termination of the reflected 
part, the mouth of the shell, a border is formed, by the edge of a regu- 
larly rounded groove, with which the shell appears to have been here 
surrounded. 
The very wide difference between its form and that of the shells of 
the genus Ammonites, to which it approaches the nearest, is sufficient, 
I conceive, to show the propriety of a separation. I acknowledge that 
I was at first disposed to consider it as a monstrosity ; supposing that 
the animal had by some accident been misdirected in its operations of 
forming its shell, and had thereby been led to the formation of it in 
this uncommon shape. A closer examination of the shell, however, 
set aside this opinion ; for I then noticed the tubercles on the sides of 
the straight part, which did not appear at all in the spiral, and but 
vol. hi. u 
