38 FOOTNOTES FROM 



and uniformly elevated land in Great Britain. These 

 species are pre-eminently Arctic and Norwegian, and pre- 

 sent many striking peculiarities which distinguish them 

 at a glance from the mosses of the woods and the valleys. 

 Though confined to the shoulders and the summits of 

 our loftiest mountains, they are common hyperborean 

 mosses, growing most luxuriantly and spreading in wide 

 patches on the rocky plains of Spitzbergen, and in the 

 upland woods of northern Norway. A few of them are 

 found on the highest mountains of Wales and the south 

 of Ireland ; while the remaining representatives of these 

 Alpine and Arctic mosses cover the projecting rocks 

 which tower up through the glaciers of the Alps and 

 the avalanches of the Pyrenees. No less than nine are 

 exclusively restricted to the very highest summits of 

 the most elevated peaks in Britain, never, except when 

 brought down by streamlets in isolated tufts along their 

 course, descending to a lower altitude than 4000 feet; 

 while upwards of twenty of the rarest species are found 

 on Ben Lawers and the lofty hills in the neighbourhood, 

 of which no less than thirteen are to be found nowhere 

 else in this country. 



Mosses, in many instances, are limited in their range 

 to rocks and soils of the same specific character; their 

 limits of distribution, and of the rocks and soils possessing 

 such character, being identical. For instance, some are 

 confined to limestone districts and chalk cliffs ; a cal- 

 careous soil being indispensable to their existence. 

 Others affect granite; numerous species luxuriate in soil 

 formed by the disintegration of micaceous schist ; while 

 not a few are found growing chiefly on sandstone and 



