364 TUTIRA 



sense the arrival of the one was natural, the arrival of the other 

 artificial, though the terms may give us pause, since every interference 

 by man with the normal course of events may also be called natural. 

 At any rate, once landed in New Zealand, the two breeds were essen- 

 tially on the same plane. Each had reached its destination in its own 

 way the wax-eye by pinion and plume, the sparrow by sailcloth 

 wings. Whatever the difference in manner of arrival may have been, 

 once landed in New Zealand the breeds were on a par as to the future. 

 Each was beyond the direct influence of man, outside his pale, free 

 to select the route of its wandering, its rate of increase, its climate. 

 In truth, we may eliminate from our minds the long sea-voyage, the 

 habitation of ships, the cramped confinement below deck. If we choose 

 to do so, we may consider that the sparrow, blackbird, deer, and weasel 

 arrived in New Zealand during the 'sixties, 'seventies, and 'eighties 

 by a series of nearly connected islands, since submerged. At any rate 

 their goal once attained, fullest liberty awaited them ; they were free 

 to pursue a future unshackled by the past. 



The behaviour of aliens " wild " in a strange land can neither be 

 compared to the seasonal migration of continental areas, nor on the 

 other hand be passed over as mere incursions, mere irruptions, such 

 as those of the sand-grouse, or the lemming, that ebb and leave no 

 lasting mark. The treks of our aliens have a certain original place 

 in the annals of migratory movement; they possess, moreover, the 

 interest that attaches to an experiment which cannot be repeated. 

 Conditions obtaining in New Zealand in the 'fifties, 'sixties, and 'seven- 

 ties no longer exist. The world does not now contain a continent 

 or a great island still virgin, still unmanned. 



The particular history of certain aliens has been described. Two 

 main facts stand out : the first, that amongst certain of the birds there 

 still survive blind and broken traces of some sort of seasonal impulse, 

 reminiscences, confused and indeterminate, of gatherings for flight. On 

 Tutira I have again and again witnessed the assemblage in autumn 

 of parties and congregations of birds, of petty local migrations. Black- 

 birds, greenfinch, and thrush gather in flights great or small ; they 

 travel somewhere for some purpose, though the whither and why will 

 remain unfathomed until individual birds are marked and watched. The 

 second fact standing forth pre-eminently is, that many of the aliens 

 have moved at the prompting of a genuine migratory impulse. 



