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H. Hamshaw Thomas. 
ments of succession : (a) Reed swamp passing into fen and ultimately 
becoming birch thicket where the peat is thick and moist; (b) 
Calcareous bog passing into Pine forest where the soil is dryer and 
more calcareous and the peat thin. In view of this it might be 
more correct to place the limestone bog in a separate formation, 
but it is nevertheless very closely allied to the fen vegetation proper. 
In another locality which I saw there was an interesting patch of 
limestone bog forming a tussocky turf of grasses with much Sclicenus 
and Eriophorum and an interesting series of orchids, viz.:— 
Habenaria odoratissima. Orcliisi ncarnata va.\\Trannsteineri. 
Epipactis palustris. Orchis pyramidalis, etc. 
Herminium vionorchis. 
Some Utricularia was growing in a pool in water which quickly 
turned red-litmus paper blue. Many pines were also springing up 
here, seedlings from the pine woods which surrounded the place. 
This limestone bog vegetation bears considerable resemblance 
to some of the calcareous bogs of Teesdale. Professor Lindman 
of Stockholm informs me that much of the bog vegetation of 
Gothland closely resembles the vegetation round Haweswater 
in Lonsdale (North Lancashire), a locality which I have not yet 
seen. The examination of such an area as has been described 
tends to show that the physical and chemical factors of the soil 
which limit existence of the floras of our northern limestone bogs 
and of the East Anglian fens, are more nearly related than might be 
supposed. 
The Pine Forest. 
Gothland, like the mainland of Sweden, is a typical forest region. 
Trees, usually pine and birch, spring up wherever there is any 
available space, and extensive forests occur. On the mainland, 
where the rock is mostly granitic and very compact, trees are able 
to colonise rocky spots which are almost bare of soil save for a few 
small pockets of humus, but in Gothland, where the limestone rock is 
well jointed and very porous they are unable to do so. Good forests 
are, however, found on the sandy and gravelly tracts of drift and in 
some places on the dry peaty deposits. Johansson divides the 
forests into two types, one characterised by an abundance of spruce 
fir, the other by the Scots pine; some smaller deciduous woods 
occur in the south, chiefly of birch and rowan ( Sorbus Aucuparia). 
The spruce-woods occur on the more loamy soils and contain such 
ground vegetation as Melampyrum sylvaticum, OxaEis Acetosclla and 
Viola sylvestris, 
