310 
APPENDIX II. 
Professor J. D. Dana’s paper 1 ‘ On the Origin of Coral 
Reefs and Islands,’ though it deals with facts already 
published more than it adduces those which are novel, is 
so important, as the work of a naturalist whose personal 
knowledge of coral reefs is perhaps unequalled, that it calls 
for a rather full abstract. Professor Dana obtained the ex- 
perience, upon which his independent testimony is founded, 
in the course of three years spent in travelling among 
coral reefs and islands in the Pacific, during which the 
reefs of Tahiti, the Samoan (or Navigator) Islands, the 
Hawaian Islands, and the Feejees were examined with 
care, and fifteen other coral islands visited, ‘ seven of 
these in the Paumotu Archipelago, one, Tongatabu, in the 
Friendly Group, two, Taputeuea and Apia, in the Gilbert 
Group, and five others near the equator east of the Gilbert 
Group — Swain’s, Fakaafo, Oatafu (Duke of York’s), Hull 
and Enderbury Island.’ 
Professor Dana calls special attention to the eastern 
half of the Feejee Archipelago, where several of the great 
barrier reefs, from ten to twenty miles long, have but one 
or two emergent peaks of land. Nanuku, for instance, has 
one little point near its south-eastern angle, ‘ a mile of 
peak within a barrier island 200 square miles in area. 
Bacon’s Isles are the last two little peaks of a still larger 
lagoon ... a dozen of the easternmost islands are actual 
atolls — the last peak gone.’ But in case it should be 
answered that these are the emergent portions of sub- 
marine volcanos, in which case the ring-shaped barriers 
become difficult of explanation, wdiile they are easy on the 
theory of subsidence, Professor Dana adds, that move- 
ment in this direction is proved by the existence of deep 
fiord-like indentations in the rocky coasts of islands, both 
of those inside of barriers, and those not bordered by reefs. 
As examples of this structure, generally admitted to be 
1 Arner. Jour. Sci. (1885), Ser. III. vol. xxx. pp. 89, 169. 
