Laing. — Revised List of the Norfolk Island Flora. 3 



not have been written. Maiden paid a short visit to the island in 1902, 

 and in the century that had elapsed between his visit and Bauer's various 

 collectors had been there : but of these only one need be mentioned here — 

 Allan Cunningham, a former Director of the Sydney Gardens. The addi- 

 tions made by Cunningham to Endlicher's list were published after his 

 death by R. Heward in Hookers London Journal of Botany, i, p. 107. This, 

 unfortunately, I have not been able to see. In addition, large numbers of 

 plants have been sent to Sydney and Melbourne by residents on the island. 

 Unfortunately, such collections have contained many introductions. The 

 collector, though with every good intention, has been unable to distinguish 

 between naturalized and indigenous species. These species have been 

 accepted by Australian botanists, in some cases too readily. Maiden has 

 been more critical, and has cut out some of them from his list ; but it seems 

 to me that there are still more, particularly among the ferns and grasses, 

 which have to be rejected. In addition to introduced species, a few plants 

 that have been listed have not been found on the island at all, but have 

 been inserted through some error as to their habitat. These are plants 

 belonging chiefly to Australia. Lord Howe island, and in one or two eases to 

 the New Hebrides. 



Though the botanist who does his own collecting on the island has much 

 better opportunities of distinguishing between naturalized and introduced 

 species, yet, owing to the conditions, it is frequently impossible even for him 

 to form a definite opinion in a given case. The chief reasons for this are 

 (1) the omnipresence of weeds already mentioned, and (2) the fact that 

 many of the introduced species are just those that might be expected to 

 occur indigenously. This is especially true of Australian plants. Constant 

 communication with Australia for more than a century has undoubtedly 

 led to the introduction not only of a large number of Australian plants, 

 but also of an unusual abundance of subtropical weeds. The mere finding 

 of a plant on the island can. therefore, no longer be regarded as a proof that 

 it. is an indigene, and other tests have to be applied : yet even with these 

 it is often impossible to'arrive at any certainty as to whether a plant is native 

 or foreign. 



Indeed, the following consideration seems to show clearly that among 

 recent additions to the flora of the island there have been included some 

 importations. Maiden gives a list of forty-six phanerogams new to the 

 island, but not one of these is endemic. Now, in Endlicher's list of about 

 a hundred phanerogams about one-third are endemic. It is very impro- 

 bable that Bauer should have discovered all the endemic species and yet 

 have neglected forty-six indigenous but non-endemic species. This impro- 

 bability is immensely increased when it is remembered that many of the 

 newly added species are well-known plants elsewhere and are abundant 

 on the island, whereas some of the endemic species recorded by Bauer are 

 now very rare, and probably always have been rare on the island. One 

 would certainly have expected to find in the forty-six species added by Maiden 

 the same percentage of endemic species as in Endlicher's list. The total 

 absence of local forms in the list is, to my mind, very strong evidence that at 

 least a fair proportion of the added species are naturalized and not truly 

 indigenous. 



Presumptive evidence to the same effect may also be derived from this 

 further consideration, though I do not wish to place too much weight upon 

 it. It is generally recognized — e.g., by Hemsley, Cockayne, and others — 

 that under similar conditions the number of species upon an island will 



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