1898.] Funafuti, Rotuma and Fiji 447 



all the reef-forming organisms. Off this platform, after a sudden 

 drop to 3 fathoms, the slope is gradual to 40 fathoms, at which 

 the steep commences ; the bottom is of sand, in most places 

 without masses or ridges. North of Taviuni 40 fathoms is often 

 reached in 100 yards, but then a flat commences with 40 — 50 

 fathoms and a breadth of 2 — 3 miles ; its edge generally falls 

 abruptly, but there are traces of a barrier in some reefs almost 

 awash with shallower soundings between. In the middle of the 

 strait is a small volcanic island, Koro Levu, which to the west and 

 south has a well-formed barrier but to the north-east a narrow 

 fringing reef; sheltered by it are a number of small isolated 

 patches. These reefs have all narrow, flat tops, covered with 

 incrusting nullipores and almost precipitous walls to 8 or 10 

 fathoms. 



Off Vuna Point to the south-west of Taviuni a barrier reef 

 runs out for 2 miles, following the line of the coast, so that it is at 

 once suggested that it is formed on a bank piled up here by 

 the current through the strait ; it is well protected too from the 

 east by a cape to the south, which is itself destitute of any reef. 

 The lagoon of this barrier has a depth of 10 fathoms and a sandy 

 bottom, the reef falling to it precipitously while the slope up to 

 the land is quite gradual. Off the south-east of Taviuni there is 

 usually some sort of a fringing reef, but only off Salia Levu is it 

 more than about 20 yards across, attaining here a breadth of 

 100 — 150 yards and having a well-defined rim, reef- flat and a boat 

 channel with a depth of 5 — 9 feet at low tide. The rim is com- 

 pletely covered with nullipores, and corals are rare both on the 

 reef-flat and in the boat channel, although the shore is strewn 

 with their branches. Outside the rim, which is similar in every 

 respect to that of Funafuti, masses almost as high extend for 

 some yards, the sea breaking on them : further out the bottom 

 is covered by masses and ridges with a fairly abundant . coral 

 growth. 



The south-west of Viti Levu is fringed by a narrow reef, 

 unbroken practically save where the Singatoke flows into the sea. 

 To the east it is succeeded by a reef of the barrier class, which 

 extends up round the east coast, until it joins the Ovalau reef; it 

 nowhere lies more than 2 — 3 miles from the shore, and there are 

 large passages in it opposite the mouths of the Navua and Rewa 

 rivers and a small passage at Suva. The lagoon between Navua 

 and Suva is broken by a stretch of fringing reef, but on to the 

 Rewa river it is deep though often very narrow. The outer part 

 of the reef does not along this area differ materially from that of 

 Rotuma, but the channels inside the reef are practically devoid of 

 corals. The reef to the lagoon slopes steeply but not precipitously, 

 and by the land there is commonly a broad platform. The lagoon 



36—2 



