T. Kirk. — Displacement of Species in Neio Zealand. 25 



Moore, F.L.S., as naturalised in New South Wales, fully 

 three-fourths are naturalised in New Zealand also ; the re- 

 mainder, consistingchiefly of plants from warmer countries, are 

 not capable of becoming naturalised here. Again, out of 103 

 species of plants recently introduced with ballast from Buenos 

 Ayres, eighty-six were already naturalised here. 



The distribution of naturalised plants in the colony follows 

 to a very great extent the same lines as those of the indigenous 

 flora : the number of species decreases rapidly southward. 

 Upwards of four hundred and twenty species are found in the 

 Auckland District, but no other district in the colony contains 

 so large a number ; less than three hundred species would be 

 found in the Wellington District. It must, however, be 

 remembered that the climate of Auckland is much more 

 favourable to the naturalisation of plants from warm tem- 

 perate climates than that of any other part of the colony. A 

 singular illustration of this has been recently given. A large 

 quantity of ballast taken on board at Buenos Ayres was dis- 

 charged at Wellington from a vessel loading for Europe. Over 

 a hundred species of plants made their appearance on the 

 ballast before the close of the second summer, the great 

 majority being plants already naturalised in the Auckland 

 District; twenty-seven species, however, had not previously 

 been observed in Wellington, and of these seventeen species 

 had not previously been seen in any part of the colony. In all 

 probability not more than two of these will become naturalised 

 — most likely only one. But had the ballast been deposited 

 on the light scoria soil of the Auckland isthmus instead of on 

 the stiff Wellington clay ii is absolutely certain that in the 

 absence of interference fully one-third would have become 

 esta.blished — probably more. I will only add, as an additional 

 reason for not expecting so large an increase in the number of 

 introductions as formerly, that during the last fifteen years 

 great improvements have been made in cleaning garden-seeds, 

 agricultural seeds, and cereals, which will not only tend to re- 

 duce the number of species likely to be introduced in the 

 future, but to prevent the yearly importation of certain species 

 which at present are but partially naturalised. Chiefly from 

 this cause certain species, such as Fumaria officinalis (L.), Lepi- 

 dium campestre (R. Br.), Papaver rliceas (L.), Githago scgetuin 

 (Desf.), Scandix pecten-veneris (L.), are less plentiful in many 

 districts than they were twenty years ago. 



Possible Extinction of Indigenous Species. 



It is scarcely to be feared that any large number of 

 indigenous species will become exterminated unless under 

 special conditions not yet realised. It has been shown that 

 the aspect of vegetation over large areas may be changed by 



