498 



ISLAND LIFE 



PART II 



strait, and had spread widely owing to the soil, climate and 

 general conditions being exactly suited to it : from the 

 north and north-east a tropical vegetation of Polynesian 

 type had occupied suitable areas in the north ; while the 

 extension southward of the Tasmanian peninsula, accom- 

 panied, probably, as now, with lofty mountains, favoured 

 the immigration of south-temperate forms from whatever 

 Antarctic lands or islands then existed. This supposition 

 is strikingly in harmony with what is known of the ancient 

 flora of this portion of Australia. In deposits supposed to 

 be of Eocene age in New South Wales and Victoria fossil 

 plants have been found showing a very different vegetation 

 from that now existing. Along with a few Australian 

 types — such as Pittosporum, Knightia,and Eucalyptus, there 

 occur birches, alders, oaks, and beeches ; while in Tasmania 

 in freshwater limestone, apparently of Miocene age, are 

 found willows, alders, birches, oaks, and beeches,^ all except 

 the latter genus (Fagus) now quite extinct in Australia.^ 

 These temperate forms probably indicate a more oceanic 

 climate, cooler and moister than at present. The union 

 with Western Australia and the establishment of an arid 

 interior by modifying the climate may have led to the ex- 

 tinction of many of these forms and their replacement by 

 special Australian types more suited to the new conditions. 



At this time the marsupial fauna had not yet reached this 

 eastern land, which was, however, occupied in the north by 

 some ancestral struthious birds, which had entered it by 

 way of New Guinea through some very ancient continental 

 extension, and of which the emu, the cassowaries, the 

 extinct Dromornis of Queensland, and the moas and kiwis 

 of New Zealand, are the modified descendants. 



The Origin of the Australian Element in the New Zealand 

 Flora. — We have now brought down the history of 

 Australia, as deduced from its geological structure and the 

 main features of its existing and Tertiary flora, to the period 



^ *' On the Origin of the Fauna and Flora of New Zealand," by Captain 

 F. W. Hutton, in Annals and Mag. of Nat. Hist. Fifth series, p. 427 (June, 

 1884). 



2 To these must now be added the genera Sequoia, Myrica, Aralia, and 

 Acer, described by Baron von Ettingshausen. {Trans. N.Z. Institute^ 

 xix., p. 449.) Many botanists, however, doubt the correctness of most 

 of these identifications. 



