POLYNESIAN- EEGION. 105 



they are chiefly, perhaps entirely, colonised by drift from the 

 other islands. 



The volcanic groups are the Ladrones, Sandwich Islands, and 

 Marquesas, to the north of the low coral zone ; and to the south 

 of it, the Salomons, New Hebrides, New Caledonia, andFeejees 

 — the Friendly Islands, Navigator's and Cook's Islands — Society 

 and Austral Islands, ending with Pitcairn's and Elizabeth 

 Island. Many of these are very lofty. Their moUuscan fauna 

 is entirely peculiar, but it has most affinity with those of New 

 Zealand and the Asiatic Islands, and great analogy with those 

 of St. Helena, Brazil, and the West Indies. 



Salomons — New Hebrides — New Caledonia— Feejees. 



The most remarkable land- shells of these islands are the great 

 auriculoid, Bulimi (e.g. B. auris-hovince and B. miltochlius of 

 the Salomons). Acicula striata and 2 sp. of Cyrena are found 

 at Yanicoro ; and Physa sinitata, Peronia acinosa and corpulenta, 

 and several Neritinas and coronated Melanias, have been ob- 

 tained at the Feejees.* 



Helix 18 Bulimus 10 Cyclophqrus 2 



Nanina 2 Partula 6 Omphalotropis 1 



Vitrina 6 Acicula 1 Helicing, 6 



Friendly Islands — Navigator's — Society Islands. 



The principal lofty and rocky islands of the southern Pacific, 

 at which land shells have been obtained, are Tonga, Samoa, 

 TJpolu, and Manua ; Tahiti, Oheteroa, and Opara ; Pitcairn's 

 Island and Elizabeth Island. Each appears to have some pecu- 

 liar species and some common to other islands ; the little raised 

 coral islet Aurora {Metia), north-east of Tahiti, 250 feet in ele- 

 vation, has four land-snails which have been found nowhere 

 else — Helix pertenuis, doedalea, Partula pusilla, Helicina trochlea. 

 " Samoa and the Friendly Islands must have intimate geo- 

 logical relations ; the same forms, and many of the same species 

 of land shells, occur on both groups ; not a single Feejeean 

 species was collected on either." (Gould.) 



Helix 13 Tomatellina 6 Cyclophorus 5 



Nanina 18 Pupa 3 Omphalotropis 6 



Bulimus 1 Succinea 12 Helicina , 13 



Partula 15 Electrina 1 



The fluviatile shells are species of Physa, Melania, Assiminea 



* The Feejees {Viti) are more nearly allied to the westward islands, such as the 

 New Hebrides, than the Friendly Islands. Succinea and Partula, so plentiful at the 

 latter, are not found at the Feejees. (Gould, U.S. Exploiing Expedition). 



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