244 Dr. Mantell’s Notice of Molluskite. 
the coprolitic nodules and concretions which occur at Folkstone. 
Dr. Fitton states, “that they resemble coprolites in their chem- 
ical composition, though no traces of animal structure are appa- 
rent in them. 'They sometimes enclose portions of shells, but no 
fragments of bone or scales of fishes have been detected. In 
some cases they are of a very irregular figure, surrounding or 
incorporated with fossil remains, especially of ammonites, the an- 
terior of which is filled up with matter of the same kind.” ‘The 
last quoted remark of this eminent geologist, bears immediately 
on the subject of the present communication. 
In the grey Shanklin sand these substances also abound in 
some localities. I have observed them in western Sussex, in 
Surrey, in the Isle of Wight near Ventnor, andin Kent. But in 
no locality do they occur in greater number and variety, than in 
the “Iguanodon quarry” of Kentish rag near Maidstone, belong- 
ing to Mr. W. H. Beusted, to whose talents, zeal, and liberality, 
geology is indebted for many important discoveries. 
Mr. Beusted having long paid attention to this subject, had the 
kindness to submit to my examination (more than two years 
since) several specimens of Rostellarize, Trigoniz, Cucullea, and 
other shells, the cavities of which were filled with a dark brown 
substance, in every respect identical with the nodular and irregu- 
lar concretions of coprolitic matter, which abound in the sur- 
rounding sandstone. At the same time Mr. Beusted expressed 
his conviction that the carbonaceous substance was derived from 
the soft bodies of the mollusca, and that the concretionary and 
amorphous portions of the same matter, dispersed throughout the 
sandstone of this bed, were fossilized masses of the soft bodies of 
the animals which had become disengaged from their shells, and 
floated in the sea, till enveloped in the sand and mud, which is 
now concreted into the sandstone called Kentish rag. ‘The evi- 
dence collected by Mr. Beusted appears to me so conclusive, and 
so confirmatory of the correctness of the opinion I have previ- 
ously advanced, that I beg to place before the Society the fol- 
lowing abstract of his correspondence with me on the subject. 
“The bed of Kentish rag in my quarry which lies immediate- 
ly beneath the stratum that contained the remains of the Iguano- 
don, abounds in the usual shells of the Shanklin sand, particu- 
Jarly in Trigoniee, (generally 'T’. aleeformis,) and there is an abun- 
dance of a dark brown coprolitic looking matter, of which I send 
