1898.] Funafuti, Rotuma and Fiji. 451 



several pools of water, 5 fathoms deep, with precipitous walls. 

 The fringing reef is about 500 yards broad with no channel, but it 

 is full of holes up to 2 fathoms deep with their sides covered with 

 true corals, Millepora and Tubipora. I obtained from this part 

 in a few days more than 50 species of true corals of 21 genera, 

 and certainly both for variety and luxuriance of coral growth it 

 was the most prolific area I saw in Fiji. Outside this is a reef- 

 flat about 40 yards broad, covered with nullipores with a few 

 species of Pocillopora and Prionastrea ; the rim is similar to that 

 of the Funafuti reef, but its fissures are not so deep. The barrier 

 reef is about 200 yards wide with but few corals ; its passages lie 

 to the east and west. The depth of the lagoon varies up to 36 

 fathoms, but to the south depths of over 20 fathoms are rare and 

 the lagoon is much filled up by shoals with precipitous walls. 

 As if in correspondence with the reef, the island is bounded to the 

 west-south-west by precipitous cliffs, while the slope to the east 

 and north is similar to that of the volcanic islands to the south. 

 The north-west corner of the island is a sand-flat with a beach 

 sand rock, similar to that of Rotuma; on it are five lava hillocks, 

 each about 50 feet high and nearly all showing signs of wave- 

 action. To the east are also areas of beach sand, but off the whole 

 of this side lies an inner fringing reef, varying in breadth up to 

 200 yards and in places exhibiting almost the typical structure of 

 such a reef exposed to the ocean ; corals, especially Millepora, are 

 very abundant on its outer face, which falls precipitously to a 

 sandy bottom with 5 — 6 fathoms of water, but incrusting nulli- 

 pores are not commonly found. To the north the barrier reef 

 joins on to that of Makongai, an island which slopes down evenly 

 on all sides from one main central peak. Its reef is of the barrier 

 class except to the east, where it is fringing, 900 yards broad with 

 pools of deep water, its lagoon is about 20 fathoms deep with 

 passages mainly to the north. Ten miles off the south end of 

 Wakaya lies the Horse-shoe Shoal, an atoll-reef with rim awash on 

 all sides except the north-west. 



Most of the islands of the Lau Group are formed of limestone 

 and so the living reefs of this group are treated together with 

 their raised reefs. The island of Koro in the centre of the whole 

 group has steep hills and slopes ; its reef to the east is of the 

 broad fringing type, but to the west is wanting. ■ Kandavu has a 

 well-marked barrier reef off its south-east, east and extreme north 

 sides, but off the rest of the island the reef is either wanting, 

 fringing, or represented by a few shoals. North-east of Kandavu 

 the North Astrolabe Reef is the barrier of an isolated rock about 

 10 feet high in its centre ; the lagoon is about 1^ miles broad but 

 only has a depth of 15 fathoms. There are two passages to the • 

 north, where the lagoon is fairly clear, while to the south it is full 



