lOO Origin of the British Flora. 



ranging throughout Europe except in the north and in 

 Britain. It is living in the Rhine. 



A certain number of our fossil-plants, though still living 

 in Britain, formerly had a range markedly different. The 

 majority of these species are northern forms, which formerly 

 occupied our lowlands, but on the passing away of the 

 cold of the Glacial Epoch could only live on our mountain 

 tops. They are Dry as octopetala, Arctostaphylos Uva-ursi, 

 Androineda Polifolia^ Loiseleiiria procumbens, Oxyria digyna, 

 Betula nana, Salix Myrsinites, Salix herbacea, Salix reti- 

 culata, Carex alpina. The Temperate species of which the 

 ancient distribution within Britain was markedly different 

 from that now existing were only three or four. 



Quercus Robur appears at one time to have grown at 

 higher elevation ; for remains of well-grown oaks occur 

 occasionally in peat mosses above the limit of any but 

 stunted trees. 



Pinus sylvestris seems to have been abundant through- 

 out Britain during part of the Neolithic Period, for its 

 cones are abundant at the base of peat-mosses and in 

 ' submerged forests.' It afterwards disappeared from the 

 South of England and only recently has been re-introduced. 



Potamogeton trichoides occurred in Sussex and Hamp- 

 shire in Interglacial times ; it is now confined in Britain to 

 Norfolk, Suffolk, and the West of Ireland. 



Najas marina, now confined to a single locality in 

 Norfolk, was formerly widely distributed. It has now 

 been found fossil in Norfolk, Suffolk, Hertfordshire, and 

 Glamorgan. 



Clematis Vitalba, L. 

 Interglacial (?) : — 



Stoke Newington, London. 



Mr. Worthington Smith has recorded leaves of this 

 plant from a Palaeolithic deposit at Stoke Newington. 



