ON THE PLANT REMAINS IN THE SCOTTISH PEAT MOSSES. 59 



Lower and Upper Forestian, or the lower zone of trees in the Upper Forestian of 

 the Highlands. 



In any case, the first arctic bed of Shetland and the Outer Hebrides must belong 

 to the same horizon as the arctic bed first described by Nathorst from the base of the 

 Swedish peat mosses. 



The Geographical Distribution of the Zones in the Peat. 



As about twenty-four districts have been investigated during the last three years 

 between the south of Scotland and the Shetland Islands, Aberdeenshire and the Outer 

 Hebrides, the geographical distribution of the principal zones and the variations shown by 

 the same horizons in different districts may now be briefly indicated. 



The following stages are represented in the peat of the south of Scotland, the High- 

 lands and the Hebrides : — 



1. Recent peat. 



2. Forest. 



3. Peat bog plants with arctic plants. 



4. Forest. 



5. Peat bog plants. 



6. Arctic plant bed. 



7. Peat bog plants. 



8. Forest. 



9. Arctic plant bed. 



It is obvious that some terminology must be used in discussing the distribution of 

 these beds, and it will be simpler to provisionally name them for the purpose of descrip- 

 tion and then point out the possible correlation of these strata with stages in the glacial 

 period for which a terminology already exists. 



The following names will then be adopted : — 



1. Recent peat. 



2. Forest bed. \ 



3. Peat bog plants with Arctic plants. I Upper Forestian. 



4. Forest bed. ) 



5. Peat bog plants. Upper Peat Bog. 



6. Arctic plant bed. Second Arctic Bed. 



7. Peat bog plants. Lower Peat Bog. 



8. Forest bed. Lower Forestian. 



9. Arctic plant bed. First Arctic Bed. 



Strata 2, 3, 4 are all classified as "Upper Forestian," for reasons which will be 

 given later. 



The First Arctic Bed. — This bed has, so far, only been met with in the Outer 

 Hebrides and the Shetland Islands. Occurring at the base of all the beds, and resting 



