500 



ISLAND LIFE 



PART II 



It is therefore no matter of surprise, but exactly what we 

 should expect, that the great mass of pre-eminently 

 temperate Australian genera should be absent from New 

 Zealand, including the whole of such important families 

 as, Dilleniacese Tremandrese, Buettneriacse, Poly galeae, 

 Casuarinese and Hsemodoracese ; while others, such as 

 Rutaceae, Stackhousieae, Rhamnese, M3rrtace8e, Proteaceae, 

 and Santalaceae, are represented by only a few species. 

 Thus, too, we can explain the absence of all the peculiar 

 Australian Leguminosae ; for these were still mainly 

 confined to the great western island, along with the 

 peculiar Acacias and Eucalypti, which at a later period 

 spread over the whole continent. It is equally accordant 

 with the view we are maintaining, that among the groups 

 which Sir Joseph Hooker enumerates as "keeping up the 

 features of extra tropical Australia in its tropical quarter,'* 

 several should have reached New Zealand, such as Drosera 

 some Pittosporeae and Myoporineae, with a few Proteaceae, 

 Loganiaceae, and Restiaceae ; for most of these are not only 

 found in tropical Australia, but also in the Malayan and 

 Pacific islands. 



Tropical Character of the New Zealand Flora Explained. — 

 In this origin of the New Zealand fauna by a north-western 

 route from North-eastern Australia, we find also an 

 explanation of the remarkable number of tropical groups of 

 plants found there : for though, as Sir Joseph Hooker has 



Cassia, Dalbergia, Eucalyptus, Diospyros, Dryandra, Casuarina, and Ficus ; 

 and also such northern genera as Acer, Planera, Ulmus, QuercuSj Alnus, 

 Myrica, and Sequoia. All these latter, except Ulmus and Planera, have 

 been found also in the Eastern-Australian Tertiaries, and we may therefore 

 consider that at this period the northern temperate element in both floras 

 was identical. If this flora entered both countries from the south, and was 

 really Antarctic, its extinction in New Zealand may have been due to the 

 submergence of the country to the south, and its elevation and extension 

 towards the tropics, admitting of the incursion of the large number of 

 Polynesian and tropical Australian types now found there ; while the 

 Australian portion of the same flora may have succumbed at a somewhat later 

 period, when the elevation of the Cretaceous and Tertiary sea united it with 

 Western Australia, and allowed the rich typical Australian flora to overrun 

 the country. Of course we are assuming that the identification of these 

 genera is for the most part correct, though almost entirely founded on 

 leaves only. This, however, is strongly contested by many botanists, and 

 fuller knowledge is requisite before any trustworthy explanation of the 

 phenomena can be arrived at. 



