64 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 
by two miles wide, leaving the basin studded with innumerable islets 
and rocks (Plates 83, 84) such as I have already mentioned. These 
islands have usually vertical faces; many of them are conical, dome- 
shaped, or mushroom-shaped, like the islands and islets inside of the 
interior basin. A similar process has been going on off the northern 
point of Fulanga, south of Quoin Hill, where the conical and dome- 
shaped and mushroom-shaped islands and islets and rocks are seen to 
pass gradually from conical or dome-shaped bluffs along the shore line 
into the negro-heads of the outer reef flat off that point. This process 
of disintegration must have been similar in every respect to that which 
has formed the sounds in the Bermudas, eating small bays into the 
faces of bluffs inland, these becoming circular with time, with only a 
narrow opening, and finally leaving merely a narrow ridge or parts of 
ridges surrounding a central basin resembling an atoll. 
FULANGA SOUTH OF QUOIN HILL. 
If the process which has been shaping Fulanga had been going on 
longer the result would have been a low ridge on the southwestern face 
of an elliptical outer reef flat, with an enclosed lagoon full of islets or 
rocks or heads, and here and there perhaps an island or islet indicating 
the former existence of the elevated coralliferous limestone ridge ; there 
being a passage into the lagoon where it now exists, the lagoon as en- 
larged including the true lagoon and the “ Sound ” basin, — a condition 
of things very similar to that found on Oneata, Ngele Levu, Yangasé, 
Nanuku, and on Vanua Mbalavu. On the faces of the islands and islets 
forming the eastern ridge of the basin of Fulanga rise vertical cliffs 
deeply undercut and weathered. The reef flats are full of negro-heads, 
some of which are of considerable size. The reef flats are everywhere 
covered with extensive stretches of flourishing corals. 
This atoll-like basin has thus in reality been formed by the wearing 
action of the sea, and subsidence has played no part in its formation; on 
the contrary, the coralliferous limestone flat covering the basin has been 
ete, an is 
