CORAL ISLANDS AND SAVAGE MYTHS. 49 
The recent peopling of these islands, as their traditions 
imply, is a noteworthy circumstance. Mr. Gill holds the 
view that not only the Hervey Group, which includes 
Aitutaki and Mangaia, but also that all the eastern Pacific 
islands have been peopled in comparatively recent times. 
“The colonisation of the Hervey Group,” as he writes, “ may 
not date back beyond five or six centuries.”* The legends, 
therefore, relating to the origin of Mangaia and Aitutaki, and 
also of Manahiki and Rakaanga, discovered as coral shoals 
by the Rarotongan fisherman, would belong to a still more 
modern period; and the origin of these living and upraised 
coral islands would, according to this view, be of a very 
recent date. ‘This is a conclusion, however, which we cannot 
accept. ‘The evidence which we possess goes to show that 
certain coral atolls of the present day have remained very 
much in their present condition for three centuries and 
more, in fact as far as reliable records take us back. Though 
accepting the traditions of the natives of the Hervey Group, 
in so far as they throw light on the mode of origin of the 
living and upraised atolls, I cannot, on account of the evidence 
that follows, assign such a modern date for the origin of 
these islands as Mr. Gill’s view of the recent peopling of the 
Hervey Group would seem to suggest. 
Both Mr. Darwin and Professor Dana give evidence of the 
extremely slow rate of growth of coral reefs; but the former 
distrusts his evidence and advances facts apparently support- 
ing the opposite conclusion, facts, however, which as he himself 
allows, afford only direct proof of the increase of the islets on 
the reef and not of the reef itself. I, however, agree with him 
that the stationary condition of a submerged coral reef or of a 
single large mass of coral may afford no proof whatever of the 
slow rate of coral growth. The fact of the coral knolls in the 
lagoon of Diego Garcia having remained at the same depth 
below the surface for a period of eighty years, and the station- 
ary level of the Dolphin Shoal off Tahiti during a lapse of 
sixty-seven years,t may be otherwise explained when we know 
more of the causes that limit the upward growth of reef corals. 
Professor Dana, however, writing many years after and with 
more recent and more exact data at his disposal, arrived at the 
conclusion that a reef increases its extent with extreme slow- 
ness. But information is greatly needed in these matters ; 
and we are scarcely in a position to form a true idea of the 
rate of growth of coral reefs. 
Of the outward growth of coral atolls, we have abundant proof 
* Journ. Anthrop. Inst., vol. iii. p. 334. 
t+ Darwin’s Coral Reefs (1842), pp. 69, 72. 
eT 
