THE EUCALYPTM OF GIPPSLAND. 1U7 



mountaiuous and littoral tracts of Gippslaud, of the several tyj^es of Eucalypts, seem 

 to me to show that elevation above sea level, rainfall, and aspect have had more to 

 do in their distribution than have the geological formations, or than have the different 

 soils produced therefrom. 



The range of mountain and littoral types has, it seems, varied from time to time ; 

 that is to say, the mountain types have at times spread into or over the littoral tracts, 

 while at others the littoral types have spread into the mountains. 



The manner in which E. piperita, E. obliqua, E. goniocalyx, E. polyanthema, 

 and others climb up the southern slopes, and tbere meet with the subalpine forms, 

 and others whose habitat is in the dry valleys within the coast range, shows that the 

 distribution of these forms is regulated by climate. 



It would only require that the conditions which now prevail on the southern 

 slopes sliould extend over the drier mountain pleateaux ; in other words, that the 

 rainfall should be greater there than it is now for those Eucalypts to extend still further 

 northwards from the lowlands. 



I have been led to suspect, from the study of the Gippsland Eucalypts, that 

 varieties have arisen, not only through the impulse of the favouring conditions of 

 climatic change, but also that to the same cause is due an emigration from the 

 lowlands to the highlands, and vice versa. 



The instance of E. goniocalyx is signilicant. It is at present almost entirely 

 confined to the cool, moist littoral regions, where the soil is good, and the cool, 

 humid gullies of the southern slopes ; it does not, in its typical form, extend across 

 the watersheds into the warmer and comparatively dry northern slopes. Its place is 

 there taken by a dwarf variety havmg marked differences. 



Were the climate to become so much altered that the same conditions obtained 

 throughout the district as are now found, for instance, at Dargo, Ensay, or Glen 

 Falloch, 1 conclude that the lowland form of E. goniocalyx would disappear, and the 

 dwarfed mountain form might take its place. The species would no longer be 

 represented by a tree reaching 2U0ft. to 260ft., with a smooth-barked massive bole, 

 but by a straggling tree with, often, a short gnarled trunk, a wrinkled strongly 

 persistent bark, scanty foliage, and a young form, in which the leaves, although 

 opposed, are not pointed-ovate or broadly lanceolar, nor having the powerful odour 

 which characterises the lowland form. 



The existence of small colonies of mountain species in the lowlands, as, for 

 instance, the before-mentioned E. pauciflora and E. viminalis [b) points, I think, to 

 survivals from a time when the climate was much colder than it is now. The 

 oscillations of level which have affected the coast line of the southern half of this 



