42 bulletin: museum of comparative zoology. 



eastern spitof Vanua Levn, which breaks up into Kioaand Rambe Islands 

 and the reef-bound platform from which they rise (Plate 4). 



On the platform of submarine denudation and erosion Xamena and 

 Vatu i thake Islands, as well as a few isolated rocks on the western edge 

 of the southeastern horn of the Yanua Levu Barrier Eeef are the only 

 I'emnants of the former southern extension of Yanua Levu. To the 

 southeast of this must have existed a dumbbell-shaped island of consid- 

 erable height, of which only the summits of Makongai and of Wakaya 

 are left (Plate 3^). 



The island of Taviuni is, with the exception of the shore fringing the 

 northern half of the island and of the point of reefs off Vuna Point, 

 destitute of reefs. The island is about 23 miles long, from five to eii^'ht 

 broad, sloping uniformly to the shores from the backbone of the island. 

 This rises to a height of over 4,000 feet. The main ridge sends off a few 

 spurs towards the northeastern face of the island. The fringing reef 

 attains its greatest width to the east of Naiselesele Point. It encloses 

 a few small volcanic islets, varying in height from GO to 90 feet, and the 

 somewhat larger island of Mbuimbani (Plate 60), lying to the south, and 

 which rises to a height of more than 400 feet. To the south the fringing 

 reef becomes again quite naiTow, and disappears at Laveine Point. 



Immediately north of Somo Somo Strait the submarine platform 

 widens. Koro Levu Islet and Phillips and McPherson Rocks are in- 

 cluded within shallow soundings covered with reef patches running out 

 from the west shore of Taviuni. At a somewhat greater distance from 

 the west shore of Taviuni within the 50 fathom line are Champion, 

 Breaknot, and Mate Rocks, and to the northeast of Xaiselesele Point the 

 submarine platform reaches its greatest width, the Gangway Rocks and 

 the bank connected with them being the most distant of the outliers of 



Taviuni. 



To the eastward of Taviuni lie the islands of Ngamia, Lauthala, and 

 Matangi, separated from Taviuni by the Tasman Strait. The plateau 

 from which these islands rise is really the extension of the shoal lying 

 to the east of Taviuni and the outer reef which extends from ]\[atangi 

 east of Lauthala and south of Ngamia, stretching across Tasman Strait 

 in disconnected patches and joining the fringing reef off Thurston 

 Point. To the westward of J^Iatangi the outer reef extends only in 

 broken patches, and is seen also in the many disconnected patches found 

 in the western part of Tasman Strait. Between Matangi and the 

 northeastern horn of the outer reef there are two passages across it. 

 The lao-oon enclosing Ngamia and Lauthala has a greatest depth of forty 



