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Show 4G8 ISLAND LIFE. (PART lJ, to the free immiD"ration of such Australian types as were suita.ble to its clima.te, and which had alTeady Teached the tropical and subt? ·opical poTtions of the eastern Australian islaml. It is here that we obtain the clue to those strange anomalies and contradictions presented by the New Zealand flora in its relation to Australia, which have been so clearly set forth by Sir Joseph Hooker, and which have so puzzled botanists to account for. But these a.pparent anomalies cease to present any difficulty when we see that the Australian plants inN ew Zealand were acquired, not directly, but, as it were, at second hand, by union with an island which itself had as yet only received a portion of the flora. And then, further difficulties were placed in the way of New Zealand receiving such an adequate representation of that portion of the fiom which had reached East Australia as its climate anJ position entitled it to, by the fact of the union being, not with the temperate, but with tho tropical and sub-tropical portions of that island, so that only those groups could be acquired which were less exclusively temperate, and had already established themselves in the warmer portion of their new home. It is therefore no matter of surprise, but exactly w bat 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 Dilleniace::e Tremandrere, Buettneriacre, Polygalere, Casuarinere, and Hremodoracem; while others, such as Rutacere, Stackhousiere, Rhamnere, Myrtacere, Proteacere, and Santalacere, are represented by only a few species. Thus, too, we can explain the absence of all the peculiar Australian Leguminosre; for these were still mainly confined mixed vegetation of dicotyledonous leaves and ferns, that in general character represent those which now constitute the flora of the country. It would appear from the recent surveys of Dr. 1-Iaast that the large saurian reptiles in the Amuri and Waipara beds, the collections of which have been added to largely during the past year by the exertions of Mr. Henry Travers, lived during the formation of these coal-seams, and coeval wilh them was a species of the Kauri tree, the leaves of which have been found imbedded with the reptilian bones.'' He goes on to suggest that ''even at this remote period, New Zealand formed part of an area that possessed an insular flora, the peculiar characters of which have been preserved to the present time." (Trans. N. Z. Inst., V. p. 423.) CITAI'. XXH.] THE FLORA OF NEW ZEALAND. 469 to the grca,t western island aloncr with the I' A . Eucalypti wh. h t 1 ' ~ . pecu Htr caClas and . ' . IC a a ater penod spread over tho whole con- ~menlt. It IS equally accordant with the view we are maintain-mg", t 1at amono· the crro h' h s· J 1 • o b ups w IC Ir oseph Hooker enumerates ;; 0 i:~~pmg up ,~he features of extra tropical Australia in its p quarter, several should have reached New Zealand such as Drosera, ~ome Pittosporem and Myoporinere, with a fe"~ Proto~core, ~ogama:ere, and Restiacere ; for most of these are not onl~ fot~nd m tropiCal Australia, but also in the M I . d Pacific 1slands. a a) an an tl .TTop.ic~l chaTacteT of the N ew Zealand Plora explained-In f ·l iS oNn ob ·m of the New Ze- a I an d £a una b Y a north-western r. oute rom J o~th-eastern Australia, we find also an explanation of the ;emt~ w !e number of tropical groups of plants found there. or o~g ' as Sir Joseph Hooker has shown, a moist and uni~ form clunate favours the extension of tropical forms in th tcmp~rate zone, yet some means must be afforded ;hem foe reachmg .a temperate. isl~nd: On carefully going through th: Ilandbook, and companng Its mdications with those of Bentham' F_~·a Australiensis, I .find that there are in New Zealand thirt ~ ~Jbht thor?ughly tropwal genera, thirty-three of which arc fou~d m Australia-mostly in tho tropical portion of it, though a few are temperate, and these may have reached it through N Zealand . I To th ese we must a dd thi.r ty-two more genera, whicehw, A 1 Th~ following are the tropical genera common to New Zealand d ustraha :- · an 1. J,{elicope. Queensland, Pacific Islands. 2. Euge~1ia. Tropical Australia, Asia, and America. 3. Passijlora. Queensland, Tropics of Old World and A · 4 ],£, · T · 1 menca, . yrst~e. ropica and Temperate Australia, Tropical and Sub-t. . 1 regwns. 1 opwa 5. Sapota. Australia, Norfolk Islands, Tropics. G. Oyatlwdes. Australia and Pacific Islands. 7. Pm·sonsia. Tropical Australia and Asia. 8. G~niostoma. Queensland, Polynesia, Asia. 0. J.f?tmsacrne. Tropical and Temperate Australia Ind · 10. Ipoma3a. Tropical Australia, Tropics. ' ra. ll. Mazus. Temperate Australia India Ch' 12 v· . ' ' mo.. . )~tex.. Troprc~l Australia, Tropical and Snb-tropical. 13. 1 ~soma . Troprcal Australia, Tropical and Sub-tropical. |