- IV - 



of life and so lay themselves under tlie inHiiencc of new conditions. A knowledge of the life-habits and 

 economy in various localities of these changed and unchanged Polynesian birds is a great desideratum. 



Ornithologically speaking, Polynesia may be divided into five main divisions consisting of the 

 following groups of islands: 



I. North-Western Polynesia; comprising the Marianne, Pelew and Caroline Islands, with 

 Ualan or Kushai and Nawodo or Pleasant Island. 

 II. Mela no-Polynesia: New Caledonia, the Loyalty Islands, New Hebrides, the Banks' and 

 Santa Cruz Islands. 



III. Central Polynesia: the Fiji, Tonga and Samoa Islands, with Rotumah, Fotuna, Niuafou, 

 Uea and Savage Island. 



IV. Eastern Polynesia: the Cook or Hervey, the Austral, Society, and Paumotu Islands as 

 far as Easter Island, the Marquesas and Penrnyn Islands and the Fanning Group. 



V. The Central Coral Islands: the Marshall, Gilbert, Ellice, Phoenix and Tokelau Islands. 



The 416 species and subspecies at present known in these five divisions may be referred to 140 

 genera, of which 24 arc peculiar to the subregion, viz: Pyrrhulopsis, Reichenbaeh : Nymphicus. Wagler; 

 Coriphilus, "Wagler; Todiramphus, Lesson; Metabolus, Bonap.; Muscylva, Lesson; Pinarolestes, 

 Sharpe; Pinaroloxias, Sharpe; Cleptornis, Oustalet; Leptornis, Honibr. et Jacq. ; Lamprolia, Finsch; 

 Drymochaera, Finsch; Trichocichla, Reichenow; Megalurulus, Verreaux; Psamathia, Hartl. et Finsch ; 

 Tatarc, Lesson; Physocorax, Bonap.; Drepanoptila, Honap. ; Chrysoena, Bonap.; Phaenorhina, Verr. 

 et Des Murs; Serresius, Bonap.; Didunculus. Peale; Rhinochetus, Verr. et Dos Murs; Pareudiastes, 

 Hartl. et Finsch. In addition to these Rectes tenebrosus H.etF. may form a new Polynesian genus; Pomarea 

 is connected with another subregion only through the widely divergent P. castaneiventris Verreaux of the 

 Solomon Islands, which Dr. Howdler Sharpe includes in this genus; Symmorplius is known outside 

 Polynesia only from Norfolk Island, and Aplonis only from that island and Lord Howe's Island. Didunculus 

 strigirostris and Rliinochetus jubatus arc well known as the only representatives of the families 

 Didunculidae and Ixhinochctidae. 



Taking the above five divisions in order, North-Western Polynesia is characterised by the 

 presence of 3 peculiar genera, Metabolus, Cleptornis, and Psamathia, and of two other Polynesian genera, 

 Tatare and Pomarea. It may be further distinguished by the occurence of such genera as Astur, Scops, 

 Asio, Cuculus, Caprimulgus, Calornis, Corone, Turtur, Caloenas, which are not found elsewhere 

 in the subregion. Oriental and Palaearctic species are more or less frequent here as stragglers or in 

 migration. Such are Falco peregrinus. Morula obscura, Aegialites cantianus, Fuligula cristata, 

 Gallinago megala, Ardetta sinensis, Nycticorax goisagi, N. manillensis and N. griseus. The 

 number of species as yet recorded from this area is 112, of which 54 — 55 are peculiar to it. The Pelew 

 Islands have 64 species, 17 of which arc autochthonous; the Carolines 61, 21 — 22 autochthonous; the Mariannes 

 up to the present only 30, of which 12 are confined to them. Three species, Myzomela rubrata, 

 Zosterops semperi and Aplonis kittlitzi are found in all three groups, but nowhere else; one, Rhipidura 

 versicolor, only in the Mariannes and Uap. Other links serve to connect the thiee groups amongst 

 themselves and with some otlier j)art of Polynesia or witii the Malay Archipelago. The islands have evidently 

 become peopled from the Indo- and Austro-Malayan subregions, the influence of the latter predominating; 

 the great majority of the genera of land birds are common to both of these subregions, a few arc 

 peculiarly Australian, and one or two noticeable for their absence there. Certain indications exist which tend 

 to show that the Pelew Islands have served as a sort of bridge for a spread of species from Indo- and Austro- 

 Malaya right across the Pacific. For instance, the genus Tatare. which is closely allied to Acrocephalus^ 

 is found in three species in North -Western, and in four in Eastern Polynesia; a species of Pomarea occurs 

 in the West Carolines (Uap) and the typical form in the Society Islands. All the islands are of coral or of 

 volcanic origin and are generally covered with a luxuriant vegetation ; mountainous volcanic ones chiefly prevail 

 in the Mariannes and Pelews, and lagoon islands in the Carolines, though the richest from an ornithological 

 point of view known in that archipelago, viz. Ponape, Kusliai or I'alan, Ruk and T'ap, are mountiiinous. 

 Full lists may be expected to show a very great increase in point of number of species in the Marianne and 

 Caroline Islands. 



