considering the greatest part of the materials of this formation as existing in the English basin, but differently modified.
For this purpose I shall consider the organic remains, which the French have observed to belong peculiarly to these beds, as very important.
The general correspondence between the fossil shells of Grignon and those of Hampshire, has been already pointed out by several able naturalists, and in particular lately by Mr. Parkinson. I should therefore scarcely have considered it necessary to state here what is already so well known, had I not been enabled during my late journey to the Isle of Wight, to add several not hitherto observed, and which bring the agreement still closer; and since organic remains furnish one of the best methods of identifying strata, or rather perhaps formations, it may at present be interesting to bring into one view the most characteristic fossils that have been observed in this formation in England.
The liberal assistance of Mr. Parkinson has enabled me not only to give the scientific names of Lamarck to the several fossil shells which I found, but also to add the corresponding Linnean names, by which they are chiefly known in this country. This however could not be done in every case, since many of the fossils of Lamarck were not known to former naturalists.