44 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
coralliferous limestones, rising on Ngele Levu to about sixty feet, on Tai 
ni Mbeka to forty feet, and on Taulalia to thirty feet. The process of 
disintegration which has taken place can still be seen going on at the 
extremities of the island of Ngele Levu. On the reef flat near it, as 
well as along the inner beach, crop out many negro-heads of elevated 
limestone rock, and between the smaller islands, which are now only 
connected by a reef flat, the islands themselves being undercut and their 
TAULALIA, NGELE LEVU LAGOON. 
surface deeply pitted and honeycombed (Plates 95, 96). On Taulalia 
many large domes of harder material, somewhat conical, still exist, 
which have not been rounded off to the general level of the island. 
We walked a good part of the length of the island of Ngele Levu, 
and crossed it at right angles. The elevated tertiary limestome rock 
was found cropping ont at all points (Plate 97), and towards the north- 
eastern shore we came upon a helt of limestone nearly devoid of vege- 
tation, which must have risen at points to fully sixty feet above the 
shore line. The surface of that part of the island was full of deep 
potholes and crevasses of all sizes and shapes, separated by ridges and 
columnar or conical masses, some of them fully fifteen feet alove the 
general level of the surrounding area (Plate 98). The rock surface in 
all directions was pitted and honeycombed, and eroded into thousands 
of sharp points and needles, the aspect of this island recalling a similar 
structure so common among the Bahamas. At Observatory Point, the 
southern extremity of the island, this very characteristic structure is 
quite well marked, and shows admirably the gradual passage of an island 
composed of elevated limestone rock into a reef flat identical in all 
respects with the reef flats surrounding the lagoon. Plate 99 shows the 
