444 ZOOLOGICAL GEOGRAPHY. [PART III. 
possess hardly anything, but what they might have received 
by immigration over a wide extent of ocean. 
Ladrone, and Caroline Islands—These extensive groups of 
small islands are very imperfectly known, yet a considerable 
number of birds have been obtained. They possess two 
peculiar Polynesian genera, Tatare and Sturnodes ; one peculiar 
sub-genus, Psammathia (here included under Acfocephalus) ; 
and ten of the typical Australian genera found in Polynesia,— 
Lalage, Monarcha, Myiagra, Rhipidura, Myzomela, Erythrura, 
Artamus, Phlogenas, Ptilopus, and Megapodius, as well as the 
Papuan genus fectes, and the Malayan Calornis ;—so that they 
can be certainly placed in the sub-region. Genera which do 
not occur in the other Polynesian islands are, Acrocephalus, (s.g. 
Psammathia) originally derived perhaps from the Philippines ; 
and Caprimulgus, a peculiar species, allied to one from Japan. 
New Caledonia, and the New Hebrides—Although these islands . 
seem best placed with Polynesia, yet they form a transition to 
Australia proper, and to the Papuan group. They possess 30 
genera of land-birds, 18 of which are typical of the Australian 
region ; but while 13 are also Polynesian, there are 5 which do 
not pass further east. These are Acanthiza, Eopsaltria, Glici- 
phila, Philemon, and Ianthenas. The peculiar Polynesian genus, 
Aplonis, of which three species inhabit New Caledonia, link it to 
the other portions of the sub-region. The following are the 
genera at present known from New Caledonia :—Twrdus, Acan- 
thiza, Campephaga, Lalage, Myiagra, Rhipidura, Pachycephala, 
Eopsaltria, Corvus, Physocorax (s.g. of Corvus, allied to the jack- 
daws), Glicphila, Anthochera, Philemon, Zosterops, Erythrura, 
Aplonis, Artamus, Cuculus, Halcyon, Collocalia, Cyanoramphus, 
Trichoglossus, Ptilopus, Carpophaga, Macropygia, Ianthenas, 
Chalcophaps, Haliastur, Accipiter. The curious Rhinochetus 
jubatus, forming the type of a distinct family of birds (Rhino- 
chetidz), allied to the herons, is only known from New Cale- 
donia. 
It thus appears, that not more than about 50 genera and 150 
species of land-birds, are known from the vast number of islands 
that are scattered over the Central Pacific, and it is not probable 
