Islands and Coral Reefs of Fiji. ' 413 



reef and the shore, as is evidently the case in ahuost all fringing 

 reefs, which show either an incipient channel where boats may 

 circulate at high water, or a belt of considerable width in which the 

 coral fringing the land has been killed by the silt brought down 

 from the adjacent slopes, and has been decomposed, and, crumbling 

 to sand or mud, is gradually being carried off at each high tide, 

 forming a channel which when wide enough and deep enough 

 becomes sufficiently prominent to change the fringing reef into 

 a barrier reef. 



"The difficulties encountered in attempting to meet the many 

 suggestions made by Darwin regarding reefs which he did not 

 examine are well exemplified in the account which he gives of Eose 

 Island, one of the Samoa group. 



" Bonney similarly takes Dana's account of the eastern half of 

 the Fiji Archipelago, as if it were based upon actual observations. 

 Dana did not visit that part of Fiji, but derived his information 

 from the surveys of these islands made by the officers of the United 

 States Exploring Expedition. His statements are derived from 

 the charts." 



General Sketch of the Fiji Islands and Cokal Eeefs. 



The following is a general sketch by Professor Alexander Agassiz 

 of the Fiji Islands and coral reefs : — 



" I went to the Fijis under the impression that I was to visit a 

 characteristic area of subsidence; for according to Dana and Darwin 

 there is no coral reef region in which it is a simpler matter to 

 follow the various steps of the subsidence which has taken place. 

 Dana, in his last discussion of the coral reef question, states that it 

 is impossible to find a better series of islands than the Fijis to 

 illustrate the gradual changes (brought about by subsidence) which 

 take place in transforming a volcanic island with a fringing reef to 

 one with a barrier reef, or to one with an encircling reef ring, and 

 finally to one in which the interior island has disappeared and has 

 left only a more or less circular reef ring. For these reasons one of 

 the Fiji atolls promised to be an admirable location for boring and 

 settling the question of the thickness of the coral reef of an atoll. 



" My surprise was great, therefore, to find within a mile from 

 Suva an elevated reef about 50 feet thick, and 120 feet above the 

 level of the sea, the base being underlaid by what is locally called 

 ' soapstone,' a kind of volcanic mud. The western extension of 

 this reef can be traced at points along the north side of the harbor 

 of Suva, the islands of Lambeko, Vuo, and Dra-ni mbotu, which are 

 respectively sixty to seventy feet in height, being parts of an 

 elevated reef extending to low water mark, and now planed off. It 

 was this elevated reef or its extension westward which we traced 

 from the Singatoka Eiver to the Nandi Waters. A short distance 

 inland from the mouth of the Singatoka there is a bluff of about 250 

 feet in height, composed of coralliferous limestone. This bluff is 

 the inner extension of the elevated patches and limestone bluffs 

 visible on the shore of Viti Levu. I am informed by Dr. Corney 



