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Show 466 ISLAND LIFE. (rART H. · 1 d stretc hm. g from far south of comparatively narrow 1S an ' . h ystalline and Secondary G · a . w h1le t e cr . . h Tasmania to New u1m Ne o'r th A us t ra1 1. a probably mdlCate t e formations of centra . I ds in that direction. ore Iarcre 1s an . existence of one or ro o . I nds-with whiCh we are d the western 1s a . . The eastern an ld then differ considerably m theu now chiefly concerned-wou A DURING THE CRETA C11:0US PERIOD. BOWING THE PROBABLE CONDITION OF A.USTRALI MAP s 1 d . the sluvlccl part~ sea. 'Ihe w~ite portiodns fr1~:~~~~o. ~~shown in outline. The extstlng lan o . . 1' f The western and more ancient land vegotatwn and amma~ 1 e. . £ t es the peculiar Australian d · 1 ts ma1n ea ur , . already possesse ' m 1 f f 1. ts strange marsupial d 1 the ancestra orms o . flora, an a so . . robabl received at some earher fauna, both of whiCh It h~d p 'th ~e Asiatic continent over epoch by a temporary umEon tw1 Australia on the other hand, what is now the Java_sea. as ern ' CHAP. XXIl.] THE FLORA OF NEW Z-EALAND. 4G7 possessed only the rudiments of its existing mixed flora, derived from three distinct sources. Some important fragments of the typical Australian vegetation had reached it across the marine 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, accompanied, probably, as now, with lofty niountains, favoured tho immigration of south-temperate forms from whatever Antarctic lands or islands then existed. 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, tho extinct Dromornis of Queensland, and the moas and kiwis of New Zealand, are the modified descendants. The Ori,qin of the Australian element in the New Zealand Flora. - ¥,T e have now brought down the history of Australia, as deduced from its geological structure and the strongly marked features of its flora, to the period when New Zealand was first brought into close connection with it, by means of a great northwestern extension of that country, which, as already explained in our last chapter, is so clearly indicated by the form of the sea bottom (See :Map, p. 443). The condition of New Zealand previous to this event is very obscure. That it had long existed as a more or less extensive land is indicated by its ancient sedimentary rocks ; w bile the very small areas occupied by Jurassic and Cretaceous deposits, imply that much of the present land was then also above the sea-level. The country had probably at that time a scanty vegetation of mixed .Antarctic and Polynesian origin; 1 but now, for the first time, it would be open I In Dr. Hector's address as Pl'esident of the Wellington Philosophical Society, in 1872, he refers to the fluviatile deposits of early Tertiary or Cretaceous age as containing valuable deposits of coal, and adds:-" In the associated sandstones and shales the flora of the period has been in many cases well preserved, and shows that at a period anterior to the deposit of the marine stratum the K ew Zealand area was clothed with a H H 2 |