5421 ON THE PHENOGAMIC VEGETATION OF 
where it continues throughout the year, unless the season 
be unusually warm. 
From a little below the summits of the highest mountains 
to a height of about 3500 feet, the more common plants are 
Salijc lierhacea, and Juncus tr'iglumis, very abundant, and 
in their true native place^ Polygonum viviparum, Aira 
alpina, Festuca vivipara^ Hieracium Halleri, Apargia 
Taraxici, which is only an alpine variety of A. autumnalis. 
Luzula spicata, Phleiim alpinum, seen only on Ben-na- 
buird, Silene maritima^ seen only on Ben Vrotan, and Aza- 
lea procumhens^ besides the plants of the highest elevation, 
and those of lower situations which ascend thus high ; for 
alpine plants do not occupy very distinct zones, their limits 
being too much influenced by circumstances to be defined 
with precision. 
Farther down, to the height of about 3000 feet, the plants 
are of the following species : — and here it becomes neces- 
sary to arrange tl\em under three divisions. 1^^, Those 
peculiar to the situation, being in their true native place : 
Saocifraga nivalis, Cerastium alpinum, Rhodiola rosea, 
the latter generally of small size compared with its state 
when on the sea-shore ; Alchemilla alpina, perfect about 
the height of 3000 feet, and disappearing lower down in 
dry places, though along the rivulets exceedingly common 
in the lowest valleys ; Cochlearia officinalis, of rather rare 
occurrence ; Oxyria reniformis, Saxifraga oppositifolia, 
Aira alpi^ia, Veronica alpina, Veronica humifusa, and 
Phleum alpinum. 9.dly, Those of the higher regions, all 
of which, excepting Statice Armeria, Salix lierhacea, and 
Silene acaulis, grow here also. Sdly^ Those of the lower 
regions which ascend thus high, of which the most general 
are the following : Vaccin'ium myrtillus, very stunted and 
without fruit; Juniperus alpina, whose true place is 
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