too Hart, Encalypts about Creswick and Clunes. [vo^xxix 



Vicl. Nai. 

 XXIV. 



the plains forming an obstacle to migration, for it is seen even 

 in those species which grow most freely on the plains. 



To sum up the difierences, E. Stuariiana, E. amygdalina, 

 E. coriacea, and E. nibida, which are found near Creswick, dis- 

 appear as we go to the north-west ; besides these, E. ovata was 

 not noticed on the bedrock or volcanic country about Clunes, 

 but only at a spring on Mount Beckworth. Its absence from 

 the plams about Clunes is a striking feature. Even the 

 Messmate becomes much less prominent and absent from much 

 of the bedrock country. On the other hand, Yellow Box, 

 which is limited in its occurrence about Creswick, becomes 

 more general. Red Stringybark is probably commoner, and 

 there appear also other species not present at Creswick — Grey 

 Box, Long-leaved Box, Yellow Gum, Red Gum, Yertchuk, 

 Red Box, and Red Ironbark. The JMessmate-Peppermint- 

 Apple forest of Creswick gives place to the Box forest about 

 Clunes. 



The explanation of the appearance and disappearance of so 

 many species within such narrow limits is to be found in the 

 conformation of the country and the climatic changes con- 

 nected with it. If a line were to be drawn from the south- 

 east of Mount Beckworth in a north-easterly direction, passing 

 south of Clunes, it would mark the boundary, approximately, 

 of several species ; very closely that of Red Gum, Yellow Gum, 

 and Long-leaved Box on the north-west, and of Swamp Gum, 

 White Sallee, and Candle bark on the south-east. Along this 

 line the country would be all open plains, rising to higher levels 

 to the south-east, and its exposure causing the winter con- 

 ditions to be intensified. The land quicldy reaches an 

 elevation at which it has no shelter from the north and north- 

 west, a quarter from which much of the winter wind comes. 

 It is also not protected from the south-west, a quarter from 

 which much rough and wet weather comes, for the Main Divide 

 in this direction is lower than much of the plain to the north- 

 east. Mount Beckworth is certainly a shelter to the country 

 immediately to the east of it, but this only affects a moderate 

 extent of country. The shelter it gives may cause a reduction 

 in the Clunes rainfall, thus also allowing the drier climate to 

 extend further south, but increasing the rapidity of the change 

 in climate as we rise to the south-east. Ihus the general rise 

 of the land, assisted by the effect of Mount Beckworth and of 

 the low part of the Divide, cause the conditions to change more 

 rapidly within a narrow belt of country. 



i\utes on Sumc of the Species. — It must be remembered that 

 notes on the soil, aspect, and other conditions favoured by 

 each species in one district are not necessarily exactly applicable 

 in other districts, in which climatic and other features may differ. 



