132 CORALS AND CORAL ISLANDS. 
we observe the same peculiarities illustrated on a much grand- 
er scale. Along the southern shores of Viti Levu, the coral 
reef lies close against the coast; and the same is seen on the 
east side and north extremity of Vanua Levu. But on the 
west side of these islands, this reef stretches far off from the 
land, and in some parts is even twenty-five miles distant, with 
a broad sea within. ‘This sea, however, is obstructed by reefs, 
and along the shores there are proper fringing reefs. 
The forms of encircling reefs depend evidently to a great 
extent on that of the land they enclose. That this is the case 
even in the Argo reef, and such other examples as offer now 
but a single rock above the surface of the enclosed lagoon, we 
shall endeavor to make apparent, if not already so, when the 
cause of the forms of coral islands is under discussion. Yet it 
is also evident that this correspondence is not exact, for many 
parts of the shores, and sometimes more than half the coasts, 
may be exposed to the sea, while other portions are protected 
by a wide barrier. 
In recapitulation, we remark, that reefs around islands may 
be (1) entirely encircling ; or they may be (2) confined to a larg- 
er or a smaller portion of the coast, either continuous or inter- 
rupted; they may (3) constitute throughout a distant barrier ; 
or (4) the reef may be fringing in one part and a barrier in 
another; or (5) it may be fringing alone: the barrier may be 
(6) at a great distance from the shores, with a wide sea within, 
or (7) it may so unite to the fringing reef that the channel be- 
tween will hardly float a canoe. These points are sustained 
by all reef regions. 
It is to be noted that the fringing and barrier reefs here 
pointed out are not the whole of the coral reef; they are only 
the portions that have been built up to the water's level. Be- 
tween them, and also outside of all, there are the submerged 
