182 president's address — section d. 



Then we come to an address : " On the Influence of Physio- 

 graphic Changes in the Distribution of Life in Australia," Kalph Tate. 

 (Presidential address, Sec. D., Aust. Assoc. Adv. Science, I., 312-325, 

 1887). This is an address of special interest to the botanist. 



Professor Tate indicated that the flora of Australia consists of the 

 following constituent elements : — 



1. " An immigrant portion, derived from at least two separate 



sources — 



(a) " Oriental, which is dominant in the littoral tracts of tropical 



Australia ; but despite the large assemblage of Asiatic 

 species, the Australian character is deeply impressed by 

 numbers, specifically and individually, of EucalyrAus, 

 Gtevillea, Phyllodineous Acacia, and others. 



(b) " Andean (including also certain species of the cool and 



temperate regions of the North Hemisphere). For the 

 most part this type of vegetation is restricted to the high 

 mountains of Tasmania, Victoria, and New South Wales. 

 The peculiarity of the Tasmanian flora is only in its 

 Alpine types. 



2. " An endemic portion, a localised type of which occupies the 



extreme south-west of the continent." 

 He divides the Australian endemic flora into three tj^pes, " to 

 which, for convenience of reference. I apply distinctive names." See 

 his plate XVIII.) 



" 1. Euronotian (lit. south-east wind), dominant in the south and 



east parts of the continent. 

 " 2. Autochthonian (lit. of the original race), restricted to the 

 south-west corner of Western Australia, and approximately 

 coinciding with the rainfall limit of 20in. 

 " 3. Eremian (lit. desert), dominant in the dry region, which has 

 its centre in the Lake Eyre Basin. It corresponds with the 

 saltbush country, and approximately coincides with the area 

 having less than lOin. of rainfall per annum. It is bounded 

 on the north and north-east by the Indio-Australian vegeta- 

 tion, on the east and south-east by the typical Euronotian 

 flora, and on the extreme south-west by the Autochthonian." 

 He then proceeds to discuss the Euronotian and Autochthonian 

 floras, but especially discusses the characteristics of the Eremian 

 region. 



This botanic region has its centre at Lake Eyre, where the average 

 annual rainfall does not exceed Sin. But despite the high temperature 

 and limited rainfall, the florula of the depressed country around Lake 

 Eyre shows that it contains (at that date, 1887) no less than 368 

 species. 



The total number of species catalogued for that portion of the 

 Eremian region within extra-tropical South Australia is 813 (1887). 

 He then notes the principal genera of endemic or exotic origin. Pro- 

 fessor Tate points out that there cannot be a doubt that the Eremian 



