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place in Eocene times. The flora shows a gradual change from 
upland-character to valley and to swamp — then lagoon con- 
ditions are traced, shingle and sea sand, and finally open sea 
deposits. A noteworthy fact is that in the marine beds we have 
fruits which, although comparatively few in number, are im- 
portant, because similar to or identical with those fromSheppey. 
j Bracklesham Series. — A mass of marine sands distinguished 
lithologically from the London-Clay series, by the presence of 
green grains. The marine fauna is totally distinct and far more 
tropical than that of the London Clay, whence it is inferred 
that these beds were deposited in a sea shut off from the more 
northern London-Clay sea. They occupy most of the Hamp^ 
shire Basin, and are traced in the London Basin as far as 
Chertsey, but their principal extension is in the Paris area. 
They appear in England to have been deposited in the quiet 
estuary of a great river, and are partly contemporaneous with 
the Bournemouth series. 
Barton Beds. — These are marine deposits occupying a limited 
area. Although separated by a greater lapse of time, their mol- 
lusca far more closely resemble those of the London Clay than do 
those of the" Brackleshams ; many species of the latter which 
had disappeared now reappearing. The fauna has in fact a 
more northern facies than the Bracklesham fauna, only twenty 
per cent., and these the more temperate mollusca, remaining. 
The Upper Bagshot Beds. — These are mostly white siliceous 
sands. Mr. Godwin- Austen has shown that the sudden succes- 
sion of sand to clay involves no physical change. The fauna, 
where present, is of the Barton type. 
The Upper Eocene . — The remainder of the Eocene strata in 
England are of fluvio-marine origin, and 560 feet thick. They are 
alternations of marine, brackish, fresh-water and occasionally sub- 
aerial deposits. They are only found in the Isle of Wight, and 
on the contiguous main-land, and the newest beds have the 
most circumscribed area. The fauna and flora are tropical, but 
show a gradually decreasing temperature. The highest bed, 
which is marine, is limited to a single hill, and contains a 
strangely dwarfed and impoverished, but purely Eocene marine 
molluscan fauna. It is thought, nevertheless, by many to be 
contemporary with European Miocenes. The divisions, purely 
arbitrary, are : — Lower , Middle , and Upper Headon, Osborne 
and St. Helens , Bembridge Limestone , Bembridge Marl , 
Hempstead fresh, water and marine. The marine beds are 
relatively most developed in the east, the fresh- water in the west 
of the island. 
Having thus glanced at the salient features of the strata 
composing the Eocene in England, I will now endeavour to 
