341 



degree of moisture, capacity for being heated, porosity, &c, lias more influence on the 

 growth of plants than its chemical composition, though the latter has an indirect 

 influence on its physical nature. 



Wanning gives examples of the domintaing influence of the chemical constitution 

 of the soil : thus he uses the terms Halophilous. Calciphobous, Calciphilous, Silicolous, 

 and Xitrophilous plants. (" Ecology of Plants," English trans., p. 67.) But, p. 71, 

 Bonnier says that certain species, restricted to calcareous soil in one district, may 

 be calciphobous in another, and indifferent to soil in a third. Jensen's observations 

 on Eucalypts (quoted in Part 66 under "Additions to Range") also prove this. This 

 is an expression of the difficulty all observers of geological formations (soils) and the 

 plants that grow upon them find. 



a 



Victoria.— A. W. Howitt's " The Eucalypts of Gippsland " (Trans. Roy. Soc, 

 Vict., II, 81, 1890), is one of the earliest critical papers, containing observations in 

 regard to the effect of geological formations and climate in this genus. 



Following are some specific notes in regard to the preference of species for certain 

 geological formations. The subject is, as he hints, a very difficult one. A priori we 

 are inclined to expect a very distinct relation between a plant and the geological 

 formation (soil) on which it grows, but in practice it is rarely that such a correlation 

 can be traced, and in many cases in which such a relation has been announced, additional 

 research shows that the relation is not as general as was at one time supposed. 



He says that E. regnans, with E. obliqua and E. globulus, in south and west 

 Gippsland, are chiefly on Mesozoic Carboniferous formations (p. 87). 



E. Muelleriana ascends hills of Upper Silurian sediment to 1,000 feet in elevation, 

 Toongabbie district. It appears to grow largest on the sands and sandy clays of 

 South G-ippsland (p. 90). 



E. macrorrhyncha grows especially upon dry ranges, on Plutonic, Metamorphic, 

 and Sedimentary formations of Silurian or Devonian Age. He has not observed it 

 anywhere on Tertiary tracts (p. 92). 



E. odorata (Bosistoana is meant) grows principally on the Miocene limestones 

 in the littoral tracts of North Gippsland (p. 95). 



E. leucoxyhn grows upon various formations, as, for instance, at Toongabbie, 

 on recent Alluviums, Tertiary clays and Upper Silurian ; at Bairnsdale, upon Miocene 

 and later Tertiary beds ; at Glen Maggie, upon Upper Silurian sandstone ; at Upper 

 Freestone Creek upon Upper Devonian conglomerates; at Noyang, upon Palaeozoic 

 Plutonic rocks; and near Buchan, upon Tertiary sands and clays. 



E. Stuurtiana is found on all formations, but he has observed it especially on 

 the Tertiary clays of South Gippsland, and on the Metamorphic and Plutonic areas 

 of Tubbitt, Dargo, and Jingallala (p. 97). 



