D2 Proceedings of the Royal Society of Victoria. 



in the Broadribb and Bemm watersheds, and along the south 

 side of the coast range in the heads of the Bemm and Cann 

 rivers. While it is patent, that many of the giant gums 

 exceed a height of 350 feet, I have not yet observed any 

 over 400 feet ; if there are any exceeding the latter length, 

 it is probably in the Arte, Goolingook, or Cabbage- 

 tree Creek valleys that they will be met with. The tallest 

 trees are not always those with the greatest diameter of 

 trunk. I have certainly measured trimks fully 4-0 feet in 

 circumference, but as a rule the taller trees measured had a 

 lesser circumference of from 20 to 30 feet. Next to the 

 Eucalypts the Acacias have the greatest range, and after 

 these the Daviesias, Haloragis tetragyna, Comesperma 

 ericinum, and Kennedya rubicunda, together with the wire- 

 Sfrass. 



The Evolution of Varietal Forms. 



Between the summits of the higher peaks, Mount Ellery, 

 Mount Kate, Mount Goonmurk, on the Coast Range, Mount 

 Tingiringy nori/h of it and the coast line, there are consider- 

 able variations in the hygrometric and other meteorologic 

 conditions, which I believe so powerfull}'^ affect the evolution 

 of varietal forms. I have elsewhere* endeavoured to point 

 out as regards the Alpine and sub- Alpine florula of South- 

 East Australia that under the slowly changing surface 

 configuration, due to prolonged sub-aerial denudation and 

 erosion, the transfer of soils, abraded and decomposed from 

 the great rock masses, and the action of their chemical 

 constituents on plant, food, &c., gradually modifying its 

 environment, may eventually result in the differentiation of 

 the varieties as to assume characters so distinct and 

 apparently constant as to justify the appelation of species. 

 Among many species which present differential characters 

 over large areas in different habitats, I would mention 

 Craspedia Richea, Daviesea latifolia ; some Heliclnysa, 

 especially Helicluysum rosmarinifolium ; some Rutacea', 

 Drimys aromatica, Hymenanthera Banksii, Claytonia Aus- 

 tralasica, Panax sambucifolius, Gentiana saxosa, Styphelia 

 •ericoides, and Microseris Forsteri. 



* Ou the Physiography of the Anstrahan Alj^s. Transactions of Austrahan 

 Association for Advancement of Science, 188 s. 



