Thus it contains seven species of Cypraea,
some larger than any existing cowry of the Mediterranean, several species of
Oliva, Ancillaria, Mitra, Terebra, Pyrula, Fasciolaria, and Conus. Of the cones
there are no less than eight species, some very large, whereas the only European
cone now living is of diminutive size. The genus Nerita, and many others, are
also represented by individuals of a type now characteristic of equatorial seas,
and wholly unlike any Mediterranean forms. These proofs of a more elevated
temperature seem to imply the higher antiquity of the faluns as compared with
the Suffolk Crag, and are in perfect accordance with the fact of the smaller
proportion of testacea of recent species found in the faluns.
Out of 290 species of shells, collected by myself in 1840 at Pontlevoy, Louans,
Bossee, and other villages twenty miles south of Tours, and at Savigne, about
fifteen miles north-west of that place, seventy-two only could be identified
with recent species, which is in the proportion of twenty-five per cent. A large
number of the 290 species are common to all the localities, those peculiar to
each not being more numerous than we might expect to find in different bays of
the same sea.
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