216 Transaction*. 



Caledonia - New Zealand migration as against an Australian immigra- 

 tion. The two flightless rails turn the balance in favour of New Zealand. 

 The distribution of the three resident land-birds not peculiar to Lord 

 Howe Island shows but a slight excess of Australian immigrants over 

 others. Stre-pera graculina extends to Australia, Halcyon vagans to New 

 Zealand, while Chalcophaps chrysochlora (perhaps introduced) is found 

 in Australia and New Caledonia. 



Eleven migrants have been recorded from Lord Howe Island, some of 

 which occur regularly in considerable numbers. Two are cuckoos, the 

 rest Charadriiformes ; all have been recorded in New Zealand, and all 

 except' Eudynamys taitensis in Australia. It is evident that the island 

 is in the line taken by these species on their migration to and from New 

 Zealand, and thus probably on an old land-line stretching northwards 

 from New Zealand. 



Of the thirteen occasional visitors which have been recorded in Lord 

 Howe Island, all are found in Australia, ten extend to New Zealand, and 

 eleven to New Caledonia or Malaya. The proximity of the Australian 

 Continent to Lord Howe Island and the direction of the prevailing winds 

 (westerly) in the south-west Pacific is sufficient to account for the pre- 

 ponderance of Australian forms in the accidental visitors to the island. 

 Of the eight recorded, only two extend to New Zealand. 



The large proportion of endemic forms in the resident land-birds of 

 Lord Howe Island points to the long period the island has been an isolated 

 spot. The existence of two brevipinnate rails belonging to genera found 

 elsewhere only in New Zealand is sufficient proof of a former land con- 

 nection with that country. That there was also land connection to the 

 north, whence these birds probably came, is indicated by the large pro- 

 portion of endemic Lord Howe Island land-birds which are allied to New 

 Caledonian forms. Corroborative evidence of a land bridge between New 

 Caledonia and New Zealand is furnished by the presence in Lord Howe 

 Island of the large land-mollusc Placostylus* It would be over this 

 bridge that the large portion of the New Zealand fauna and flora show- 

 ing Malayan affinities migrated. As the two flightless rails mentioned 

 above are closely allied to New Zealand forms, it is probable that the 

 land bridge was severed in the north before the connection with New 

 Zealand was broken. Lord Howe Island would therefore properly belong 

 to the New Zealand biological region. Australia can have no claim 

 whatever to include Lord Howe Island within its regional limits, as a 

 permanent ocean-basin separates the island and continent, and what 

 birds of Australian origin are found in Lord Howe Island have crossed 

 the intervening tract of ocean, yet in spite of the proximity of the con- 

 tinent have not outnumbered the New Caledonian and New Zealand forms 

 except in those groups which I have designated occasional and accidental 

 visitors. 



Norfolk Island. 



There are twelve endemic species of land -birds (including Aplonis 

 fuscus). Of these, four — Hemiphaga spadicea, Nestor productus, Cyanor- 

 hamphus cooki, Gerygone modesta — are related to New Zealand species; 

 two — Rhipidura pelzelni, Pachycephala xauthoprocta — to Australian 

 species; four — Petroica midticolor, Diaphoropterus leucopygius, Turdus 

 fidiginosus, Aplonis fuscus — to New Caledonian species; and there are 

 two species of Zosterops. Numerically the New Caledonian element pfe- 



Hedley, Proc. Linn. Soo. N.S.W.. vol. 7 (JS92), p. 335. 



