Hart — Planta of some of the Moujifain Ranges of Ireland. 245 



to the Ordnance Survey. The Sawel and Dart mountains are an 

 utterly monotonous and featureless range of wide moors and heather- 

 clad humps of schists, quartzites, and metamorphic limestones, reach- 

 ing an elevation of 2240 feet at Sawel. This group is usually called 

 the Sperrin Mountains. On the north side of Dart, at 1750 to 1850 

 feet, is a small area where a few alpines still hold their ground. Else- 

 where the common species have it all their own way. 



One record of great interest I failed to verify. Ruhus chammnorus 

 has its only Irish locality "on the top of Glengana mountain, in the 

 Stranagalwilly range, to the west of Dart, close to the boundary between 

 the counties of Tyrone and Derry," where it was found by Professor 

 Murphy in 1826. I found an old fellow in Stranagalwilly who knew 

 the name Glengana, and directed me to it, which was that part of the 

 range called on the Ordnance map Mullaghclogher. From this I 

 walked the whole range, and searched especially those summits west 

 of Dart, but altogether failed with regard to the cloud-berry. I also 

 made numerous inquiries amongst shepherd lads and others for a berry- 

 bearing plant, which the Rev. Mr. Ross, of Dungiven, has promised to 

 continue for me, and I trust the plant may be re-discovered ; but a 

 more unlikely range for any variety in the alpine flora I have not yet 

 set foot on. 



Omitting the ubiquitous lowland species which reach all summits, 

 except where there is insufficient soil, I will include all my Derry 

 notes in one Table in descending order. Many lowland species seem 

 capable of extending to a higher zone on the warm and fertile trap 

 rocks : into these I shall go with some detail. 



The correspondence between the lingering vestige of an arcti® 

 flora met with on Ben Evenagh vegetation, and that I have observed 

 along the trap rocks, a few hundred feet above the sea west of English- 

 man's Bay, in Disco, in lat. 69° 15', struck me forcibly, and is, I 

 think, worthy of quoting. Thus, the following are characteristic and 

 common to both localities : — 



Saxifraga oppositifoUa, Dryas octopetala, 



Stlene acaulis, Plantago maritima; 



Draha incana, 



while Alsine verna, Saxifraga sponheimica, Plantago maritima, and 

 Campanula rotundifoUa have their closely allied representation in 

 the arctic station, viz. Alsine hiflora, Saxifraga caspitosa, Campanula 

 rotundifoUa, var. linifolia ; and this enumeration comprises the major 

 part of the flora of the two stations quoted. This coincidence at so 

 vast a distance across the ocean (seventeen or eighteen hundred miles) 

 illustrates at once the source of our arctic flora, and the geological 

 instincts of some of its members. Some of these plants as Pryas 

 alsine and Silene, &c., also thrive on limestone, and whether there be 

 a similar constitution in the derivative soils is a question of interest. 

 I believe it is the presence of highly alkaline zeolites in the friable 



2 E2 



