XV111 



INTKODUCTION. 



just below the snow-line on the highest of the Tararua ranges, where, he states, he could have 

 collected many more. For the present, I confess that the presence of this species in the North 

 Island is very perplexing. One solution that suggests itself to my mind is that it may have been 

 introduced in former times through human agency. It will be remembered that the Maoris have 

 a tradition that the Pukeko, or Swamp-hen (Porphyrio melanonotus)— which, until recent years, 

 when its haunts were invaded and drained, was excessively abundant in both Islands — was first 

 introduced by their ancestors, who brought tame birds with them in their canoes from Hawaiki. 

 It must be borne in mind also that the range of the Grey Kiwi includes the north-west coast of 

 the Nelson District, for specimens which I obtained from that locality have been referred by Mr. 

 Eothschild to his Apteryx occidentalis ; and, furthermore, that the passage to and from the 

 Kapiti coast, on the opposite side of Cook Strait, could easily be effected by the Maoris in their 

 war-canoes. To entrap a few Kiwis, and bring them across alive in flax cages, would have been a 

 very simple operation, and a far less ambitious project than that of stocking New Zealand with 

 the Swamp-hen from far-off Hawaiki. The suggestion does not seem an unlikely one, when we 

 remember that the Kiwi was always highly prized by the Maoris from the earliest times, both as 

 an article of food and on account of its feathers. 



On the theory put forward, and assuming, as we fairly may do, that the North and South 

 Islands have never been united since the continental submergence — in other words, that there 

 was a simultaneous elevation of the two areas, north and south, with a permanent sea-channel 

 dividing them — we can understand and account for the existence of closely-allied representative 

 species in the two Islands. I will give some examples : in the North Island, the Blue-wattled 

 Crow (Glaucopis wilsoni) ; in the South, the Yellow- watttled Crow {Glaucopis cinerea) ; in the 

 North Island, the Saddle-back {Greadion carunculatus) ; and in the South, its grey ally, Greadion 

 cinereus. It is true that Greadion carunculatus is found also in the South Island, which is the 

 proper home of Greadion cinereus. This may, I think, be accounted for by an accidental colonisa- 

 tion at some time, through the crossing of stray individuals to the other side of the Straits : even a 

 single pair would suffice. Eare as this bird now is along the wooded shore on the north side of 

 Cook Strait, I can remember that, about forty years ago, it was more abundant there than in any 

 other part of the country. But to resume my list of examples : in the North Island we have the 

 Thick-billed Thrush {Turnagra tanagra) ; in the South, the common Turnagra crassirostris ; in 

 the North Island, the Wood-robin (Miro albifrons) ; in the South, its congener Miro australis ; in 

 the North Island, the Whitehead {Glitonyx albicapilla) ; in the South, the Yellowhead {Glitonyx 

 ochrocephala) ; in the North Island, the White-breasted Tomtit (Muscitrcea toitoi) ; in the South, 

 the Yellow-breasted Tomtit {Muscitrcea macrocephala) ; in the North Island, the Pied Fantail 

 {Rhipidura flabellifera) ; in the South, the Black Fantail (Rhipidura fuliginosa). The same 

 remark applies to the former of these as to the Saddle-back, and the same explanation may be 

 offered. It will, perhaps, be objected that this bird is too weak-winged to cross the Strait 

 under any circumstances ; but, as against this, I may mention that during the past twenty years 

 there have been several well-authenticated cases of the Black Fantail crossing the Strait to 

 the North Island ; and of late years there has not been wanting evidence of its breeding there. 

 What, therefore, is there to prevent such a species becoming naturalised in the North Island, 

 and that without the intervention of any but natural causes ? A gale of wind, under favourable 

 conditions for the passage of the Strait (about 18 miles) would alone be sufficient to occasion 

 this dispersal of the species. 



In addition to the cases enumerated above, I may instance the remarkable Ground Owl 

 (Sceloglaux), of which, as we now know, there were two species — the White-faced Owl (S. albifacies) 

 now on the border-land of extinction, confined to the South Island — and the smaller, Kufous-faced 

 Owl (8. rufifacies), now presumably extinct, which inhabited the North Island. Of this latter 



