Alpine and Arctic Floras 
has been done both in the Berlin and in the Zurich 
botanical gardens, it changes into Juniperus communis. 
This has been tried both with seeds and by transplanting 
a mature specimen. 
The distribution of Juniperus nana is very interesting. 
It occurs in the Scotch highlands, Wales, and West- 
morland, to 2700 feet altitude. It is also found in the 
Alps and Caucasus, to 3575 metres (11,600 feet) altitude 
in the Himalayas, and it is also widely scattered over 
the arctic regions both of America, Europe, and Asia. 
Its growth is extraordinarily slow. An ancient plant 
103 years old was only 48 mm. in diameter (1.1811 
inch) and increased in thickness by only .g mm. per 
annum (.035633 inch per annum), 
This dwarf, stunted habit of many alpine and arctic 
plants may be quite simply explained by the fact that 
they have a very short season to grow in, and therefore 
have neither time nor (at least in Tibet and Siberia) 
water enough to become of a respectable size. 
Some of our far too hardy and adaptable weeds seem 
to thrive both at great altitudes in the Caucasus or 
Tibet, and in the arctic regions, as the following short 
list clearly proves :— 
Lapland 
Caucasus. | Tibet. or Perthshire. t 
|Siberia.* 
Ranunculus acris (buttercup) , _— + + 3980 feet 
Taraxacum officinale (dandelion) . 4 + + 3900 ;, 
Festuca ovina (sheep’s fescue) . + + +  |atalllevels 
Capsella bursapastoris pepuerels 
purse). 1-2 inches | — + 1750 feet 
Euphrasia officinalis (eyebright) + _ + 3500 ,, 
Poa annua . + = + 3980 ,, 
But in Switzerland, or even in our own mountains, 
* Sewell.6 Tt White, 
95 
