THE VICTORIAN NATURALIST. 65 



upper regions of the mountains the tree-growth ceases, and a belt 

 of stunted bushes and herbs continues, occasionally covering 

 large areas with unbroken vegetation, or forming patches amongst 

 rocks. The term generally applied to this region is the " Alpine 

 region," and the vegetation thereon is known as the " Alpine 

 flora." This paper deals exclusively with the " Alpine flora" and 

 not with the " flora of the Alps," by which expression a flora is 

 understood whicli would comprise plants growing in all eleva- 

 tions of the Alps in question. It must not be understood, how- 

 ever, that the Alpine flora forms a distinct geographical or 

 systematic class of vegetation, for this is not the case in either of 

 the Alpine flora. 



It is generally accepted that the lower border of the Alpine 

 regions is formed by what is known as the tree-line ; but, clear as 

 this definition may appear, it cannot be strictly accepted as such, 

 for the following reasons : — The tree-growth does not cease 

 abruptly, but gradually becomes more and more stunted, and in 

 the shade of these bushes grow plants which decidedly belong to 

 the Alpine flora. In every case there is a considerable over- 

 lapping of the Alpine and the lowland flora. 



The most important characteristic of an Alpine flora in general 

 is therefore to be found in its habit — its physiognomy — which is 

 the product of many and varied factors, such as soil, temperature, 

 air, moisture, situation of mountains and their incline, and other 

 influences. 



A striking difference between the Australian and European 

 Alpine vegetation is noticed as regards the tree-line. Careful 

 examinations and records have established the tree-line of the 

 Eastern Alps of Europe at 5,700 feet approximately (in the 

 western part of the Alps even 6,400 feet), whereas, in my 

 estimation, the tree-line in the Victorian portion of the Australian 

 Alps is at 5,300 feet approximately — that is, 400 feet lower than 

 in the Eastern Alps of Europe. Mr. J. H. Maiden, F.L.S., 

 Government Botanist of New South Wales, in his pamphlet, 

 " A Second Contribution towards a Flora of Mount Kosciusko " 

 (1899), says: — "The height of the tree-line is fairly constant 

 (about 6,500 feet)." I have taken the tree-line in the Victorian 

 portion of the Australian Alps to be where the normal growth of 

 forest trees ceases, at 5,300 feet, and have not taken into con- 

 sideration the dwarfed tree-growth into which the normal growth 

 is transformed. Mr. Maiden, however, does not explain in his 

 pamphlet the basis adopted by him for his statement. No doubt 

 the greater height and possibly more favourable conditions in 

 the Kosciusko group may explain the difference in the tree-line. 



The diff'erence between the European and the Victorian Alps 

 is all the more striking when we consider their respective 

 geographical positions. The high plains of Bogong and Omeo 



