124 THE VICTORIAN NATURALIST. 



by birds and animals which feed on both, and are themselves 

 influenced by such conditions. A perusal of the town and 

 country papers cannot but impress the most casual observer that 

 the people in the country attach considerable importance to the 

 early and late blossoming of p'ants, conditions of crops and 

 orchards, the times and appearances of insects, especially those 

 classed as pests to agriculture and horticulture, and the migration 

 of birds, especially those protected by the Game Act, as witness 

 the recent press discussion on the wild duck. All these show 

 that the public taste is more in sympathy with biological than 

 physical data regarding the methods of distinguishing climate and 

 the advantages thereof. On the other hand, writers on climat- 

 ology do not recognize its importance, but trust too implicitly to 

 mere averages of meteorological data, forgetting that similar 

 averages may result from very different ranges of climatic con- 

 ditions. It is the extremes of temperature, moisture, &c., which 

 determine the character of the vegetation of a locality or district, 

 and these are also the conditions which determine the character 

 of a health resort. 



Plants and trees, moreover, may be looked on as natural 

 registering " weather-glasses " of different degrees of sensibility. 

 Some botanists assert that what may be termed the zero, or 

 stationary condition, of vegetation is at 6 deg. C. (about 42 deg. 

 F.) and that the various phases of plant life depend on the 

 accumulated heat to which they are exposed; and many observa- 

 tions and calculations have been made with the object of testing 

 the truth of this theory, especially on plants which are of economic 

 importance. The Government Astronomer informs me that our 

 zero would be 3 deg. F. higher than Europe, or 45 deg. F., as the 

 standard. In this way the temperature equivalent of our flora 

 can be determined, and also, in a less definite way, their moisture 

 equivalent. The reverse of this is also true. The blossoming of 

 the various plants indicates the existence of their temperature and 

 moisture equivalents — facts of extreme interest to farmers and 

 gardeners as well as to meteorologists, which would be greatly 

 enhanced in value if we were able to possess a similar set of 

 observations on the germination of seeds and the ripening of 

 fruits and seeds. 



For observation the best scheme to be adopted would be to 

 follow that admirably laid out by the Government Botanist in the 

 " Key to Victorian Plants," part 2. Taking them in their order 

 as laid down by him we have : — The north-western region, from 

 the sources of the watercourses in the north-west to the River 

 Murray, which includes Echuca, Kerang, Swan Hill, the valley 

 of the Glenorchy, and Mildura. In the south-west region, from 

 the sources of the watercourses in the south-west to the coast 

 west of Cape Otway, and to the vicinity of the Glenelg River, we 



