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Show 458 ISLAND LIFE. [rAU'l' II. believe no two other similarly situated countries in the globe present. Everywhere else I rec:ognise a parallelism or harm~ny in the main common features of contiguous floras, whiCh conveys the impression of their generi~ affin~ty, .at least, being affected by migration from centres of dispersi~n I~ one ~f them, or in some adjacent country. In this cas.e it IS ;videly ~Iffer?n~. Recrardina the question from the Australian pomt of VIew, It IS im;ossibl~ in the present state of sci~n?e to reco~cile the fa?t of Acacia, Eucalyptus, Oasuarina, Oallttrts, &c., bemg absent m New Zealand, with any theory of trans-oceanic migration that may be adopted to explain ~h~ presen~e of other Au~tralian plants in New Zealand; and It IS ver! difficult to co~celVe of a time or of conditions that could explam these anomahes, except by going back to epochs when the pre:valent .botanical as well as geographical features of each were widely different from what they are now. On the ~other hand, if I regard the question from the New Zealand point of view, I find such broad features of resemblance, and so many connecting links that afford irresistible evidence of a close botanical connection, that I cannot abandon the conviction that these great differences will present the least difficulties to whatever theory may explain the whole case." I will now state, as briefly as possible, what are the facts above referred to as being of so anomalous a character, and there is little difficulty in doing so, as we have them fully set forth, with admirable clearness, in the essay above alluded to, and in the same writer's Introduction to the FloTa of New Zealand, only requiring some slight modifications, owing to the later discoveries which are given in the Handbook of the New Zealand Flora. Confining ourselves always to flowering plants, we find that the flora of New Zealand is a very poor one, considering the extent of surface, and the favourable conditions of soil and climate. It consists of 935 species, our own islands possessing about 1,500; but a very large proportion of these are peculiar, there being no less than 677 endemic species, and thirty-two endemic genera. Out of the 258 species not peculiar to New Zealand, no less than 222 are Australian, but a considerable number of these OllAr. XXII.] THE FLORA OF NEW ZEALAND. 459 are also Antarctic, South American, or European; so that there are only about 100 species absolutely confined to New Zealand and Au~tral~a, a~d, what is important as indicating a somewhat recent ImmigratiOn, only six of these belona to genera which are peculiar to the two countries, and hardly bany to the larger and. mo.re important ~ustralian genera. Many, too, are rare species In both countnes and are often alpines. Far more important are the relations of the aenera and families of the two countries. All the Natural Ord~rs of New Z~aland are found in Australia except three-Coriarire, a widely-scattered group found in South Europe, the Himalayas, and the Andes ; Escalloniere, a widely distributed group; and Chloranthacere, found in Tropical Asia, Japan, Polynesia, and South America. Out of a total of 303 New Zealand genera, no less than 251 are Australian, and sixty of these are almost peculiar to the two countries, only thirty-two however being absolutely confined to them. In the three large ordersCompositm, Orchidere, and Graminere, the aenera are almost identical in the two countries, while the sp~cies-in the two former especially-are mostly distinct. Here then we have apparently a wonderful resemblance between the New Zealand flora and that of Australia, indicated by more than two-thirds of the non-peculiar species, and more than n.ine-tenths of the non-peculiar genera (255) being Austrahan. But now let us look at the other side of the question. Th~r~ are in Australia seven great genera of plants, each contmnmg more than 100 species, all widely spread over the country, and all highly characteristic Australian forms,-Acacia, .E~~calyptus, Melaleuca, Leu.copogon, Stylidium, Grevillea, and Halcea. ·.These are entirely absent from New Zealand, except ?ne speCies of LeucCYpogon, a genus which also has representatives In the Malayan and Pacific Islands. Sixteen more Australian genera have over fifty species each, and of these eight are totally abse~1t from New Zealand, five are represented by one or two speCies, and only two are fairly represented; but these ·twoDrose1' Ct and Helichrysum, are very widespread genera, and might have reached New Zealand from other countries than Australia. |