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of the Recent Flora of Britain . 
The specimens from Southampton Dock were received from 
Mr. Whitaker ; those from the Tilbury and Albert Docks 
from Mr. Spurred. Those from other English localities are 
nearly all of my own collecting. 
Age of the Plant-bearing Deposits. 
Roughly, the deposits from which plants have been obtained 
may be divided into Postglacial, Interglacial, and Pre- 
glacial. 
The first group includes the ‘ submerged forests,’ and con- 
temporaneous upland deposits ; raised marine deposits, like 
the Clyde beds ; and beds with arctic plants, lying directly 
above the latest boulder clay of the district. This group is 
apparently separated from the next one by a period of intense 
cold. 
The second group includes all beds which underlie boulder 
clay, but are newer than the Cromer Forest-bed. These are 
cut off from both the newer and older deposits by periods of 
intense cold and glaciation. With these may be classed the 
bed with arctic plants which underlies the lowest boulder- 
clay in Norfolk. 
The third group contains the Cromer Forest-bed, which 
underlies all the glacial deposits, and forms the highest 
portion of the Pliocene formation. 
It is not suggested that the different beds in each group are 
exactly contemporaneous, but that they occupy somewhat 
similar positions in the series. For instance, further study 
may show that there are several interglacial periods grouped 
together in section 2 , but at present I see no means of 
separating them. Some of the postglacial deposits in the 
south of England may also be equivalent to interglacial 
deposits further north. But this point also cannot yet be 
settled. 
Commencing with the newest group, the prehistoric peat of 
the mountain districts has been very imperfectly searched, the 
only sample examined being one given me by my colleague, 
