244 Scottish Mountain Plants. [Sess. 



While these changes take place, mountain floras, however, 

 are usually isolated from interferences due to land cultivation 

 and traffic, and may be peculiarly instructive in instances 

 where the lowland floras have become much altered by civil- 

 isation. If any portion of a fertile country is likely to hold 

 what is called a virgin or indigenous flora, it is most likely 

 to be found in a mountainous part. But, of course, even 

 mountainous districts are not always free from lowland traffic. 

 Such plants as the Holly appear in isolated plants in very 

 out-of-the-way districts, brought probably by fruit - eating 

 birds. In Scotland the ISTettle not infrequently ascends with 

 the cattle or sheep — in fact, this social plant is seldom absent 

 from the track of man, as M. Lavall^e has pointed out. On 

 the Continent goats are the principal carriers of lowland 

 plants to mountain heights, and colonies of weeds are not in- 

 frequently to be found in the vicinity of their mountain 

 shelters. Occasionally man himself is the introducer, some- 

 times as a designing rather than an accidental one, as when 

 the Continental Primula Auricula and Erinus alpinus were 

 found — planted or sown by hand, of course — near Glen Shee. 



There are certain plants which, if introduced, might play 

 havoc with an indigenous mountain flora. Such an occur- 

 rence is actually taking place to-day in New Zealand. Some 

 of the most vigorous mountain plants of these islands, such 

 as the large New Zealand Flax (Phormium) and the enormous 

 Wild Spaniards (Aciphyllas), which form huge rosettes of 

 rigid sharp-pointed leaves, are, according to Mr T. Kirk, being 

 ousted from their haunts by the vigorous growth and com- 

 petition of introduced Grasses and Clovers. The pressure 

 that sturdy aliens of the lowlands can exert on even a moun- 

 tain flora may be particularly well observed from their begin- 

 nings in New Zealand, where large tracts of the country have 

 only within recent years been opened up. 



Mountains as Plant Asylums. 



From the preceding it may be gathered that a mountain 

 flora is less liable to change than a lowland one. The exact 

 Toh that mountains have played as places of refuge for plants 

 driven from the lowlands by land cultivation, &c., would form 



