534 ALTERATION IN FLORA SINCE 



Some of the indigenous species are quite as aggressive, or even more 

 so, than any of the introduced. In primeval New Zealand each would 

 have its place in the association to which it belonged — there would be no 

 aggression ; but when the balance of nature was upset by the fire or cultiva- 

 tion of Maori or European, then the plants best equipped for occupying 

 the new ground become dominant, their "adaptations" for that purpose 

 fortuitously present. The miles on miles of Leptospermum scoparium and 

 Pteridium esculentum were absent in primitive New Zealand. So, too, the 

 pastures of Danthonia semiannularis in Marlborough, and the many acres 

 of Chrysobactron Hookeri in the lower mountain region of Canterbury. 

 Celmisia spectabilis, an apparently highly specialized herb for alpine fell- 

 field or tussock-steppe conditions, is now on the increase in many montane 

 parts of the Ashburton-Rakaia mountains and valleys, owing to its being 

 able to withstand fire, the buds being protected by a close investment of 

 wet decayed leaf-sheaths. 



Nor are all the introduced species aggressive, by any means. Some can 

 barely hold their own; others are limited to certain edaphic conditions. 

 Thus, Glaucium flavum, Crantz, occurs, as yet, only on the coast of Wel- 

 lington, chiefly in the neighbourhood of Cook Strait. It is confined to 

 gravelly or stony shores, and appears unable to grow on the clay hillside. 

 And yet where the latter is, in one place near Lyall Bay, covered with 

 gravel there is a large colony of the plant, whence none have found their 

 way on to the adjacent hillside. Lupinus arboreus, now so common on 

 New Zealand dunes, appears unable to spread beyond the sandy ground i. 



The fortuitous introduction of foreign species of animals and 

 plants into the country has been going on continuously since the 

 European settlement of New Zealand began. This was first brought 

 to my notice when we settled in Southland, and took up a farm there. 



In 1870 we imported from Messrs Lawson and Sons, Edinburgh, 



a quantity of grass-seed for permanent pasture invoiced to contain 



the following species: 



Alopecurm pratensis Phleum pratense 



Anthoxanthum odoratum Poa nemoralis 



Trisetum flavescens „ pratensis 



Dactylis glomerata „ trivialis 



Festuca elatior Lotus cormculatus 



„ duriuscula „ major 



„ heterophylla Medicago lupulina 



„ pratensis Trifolium pratense 



„ rubra . „ hybridum 



Lolium perenne „ repens 



In addition to these the following appeared, the ground being 



newly broken up — and having never previously been cultivated : 



Chrysanthemum leucanthemum Ononis arvensis 



„ segetum Anthyllis vulneraria 



Lychnis Githago Vicia sativa 



Geranium molle Knautia arvensis 



'^ The latest expression of views on this interesting subject will be found in 

 Dr Cockayne's New Zealand Plants and their story, Chap. X (Wellington, 1919). 



