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the possibility of the plants of the Southern Ocean being the remains of a flora 

 that had once spread over a larger and more continuous tract of land than now 

 exists in that ocean ; and that the peculiar Antarctic genera and species may 

 be vestiges of a flora characterized by the predominance of jflants which are 

 now scattered throughout the southern islands. An allusion to these specula- 

 tions was made in the ' Flora Antarctica,' where some circumstances connected 

 with the distribution of the Antarctic islands were dwelt upon, and their 

 resemblance to the summits of a submerged mountain chain was pointed out ; 

 but beyond the facts that the general features of the flora favoured such a view, 

 that the difficulties in the way of transport appeared to admit of no other 

 solution, and that there are no limits assignable to the age of the species that 

 would make their creation posterior to such a series of geological changes as 

 should remove the intervening land, there was nothing in the shape of evidence 

 by which my speculation could be supported. I am indebted to the invaluable 

 labours of Lyell and Darwin, for facts that could alone have given countenance 

 to such an hypothesis ; the one showing that the necessary time and elevations 

 and depressions of land need not be denied ; and the other, s that such risings 

 and sinkings are in active progress over large portions of the continents and 

 islands of the Southern Hemisphere. It is to the works of Lyell that I nnxst 

 refer for all the necessary data as to influence of climate being dependent on 

 geological change. In the ' Principles of Geology ' these laws are proved to 

 be of universal application, and amply illustrated by their being applied to the 

 elucidation of difficult problems in geographical distribution. It follows from 

 what is there shown, that a change in the relative posibions of sea and land has 

 occurred to such an extent since the, creation of still existing species, that we 

 have no right to assume that the plants and animals of two given areas, 

 however isolated by ocean, may not have migrated over pre-existing land 

 between them. This was illustrated by an examination of the natural history 

 of Sicily (where land-shells, still existing in Italy, and which could not have 

 crossed the Straits of Messina, are found imbedded on the flanks of Etna, high 

 above the sea-level), regarding which Sir Charles Lyell states that most of the 

 plants and animals of that island are older than the mountains, plains, and 

 rivers they now inhabit." 



You will, then, observe that although New Zealand presents all the 

 characteristics of, and is properly treated as a distinct province for the purposes 

 of a description and classification of its animal and vegetable life (for the 

 remarks I have quoted in regard to its Flora apply also to its Fauna,) yet it must 

 also be considered as forming a part only of a greatly larger area, within which 

 the Fauna and Flora exhibit such a degree of affinity, as can only be accounted 

 for by the former existence of means of inter-communication, of which all 

 visible traces are now lost. In this connection, for example, it is highly 

 interesting to know that except one or two plants not found in New Zealand, 

 the whole Flora of the Chatham Islands, four hundred miles to the eastward 

 of Banks' Peninsula., is absolutely identical with that of these islands, although 

 some of the forms (as for example, Lomaria discolor, a common fern in our forests) 

 have been somewhat modified in outward appearance, a fact itself of great and 

 striking significance in connection with the views of Mr. Darwin. The same 

 remarks also apply to the Flora of Raoul or Sunday Island, a small island some 

 six or seven hundred miles to the north-east of the northern part of New Zealand, 

 with this increased difficulty in accounting for the general identity between the 

 two Floras (except on the supposition of a former extension of the land of New 

 Zealand, as to include the several islands referred to) that the prevalent winds and 

 the ocean currents between this country and Raoul Island, would di'ive us to the 

 conclusion, that the former had been colonized from the latter, a supposition op- 

 posed to all our present knowledge in regard to the origin and distribution of life. 



