CORAL REEFS. 141 



a platform for coral growths. He states that the Maldives stand 

 on a coral swept plateau 190 fathoms below the sea level. On this 

 banks have been built up and reefs have grown on them, and they 

 have gradually extended outwards. Atolls arise from the fusion of 

 reefs and the washing away of their interior portions as the circum- 

 scribing reefs became more perfect. He supported the theory partly 

 by a comparison between soundings made in the middle of the 19th 

 century and those made by himself. The accuracy of the early 

 soundings was questioned by Admiral Wharton. 



(5) Wood-Jones, 1910.1 — Corals grow only above the limiting 

 level of sedimentation. Atolls may often be developed from a reef 

 by the distribution of detrital matter derived from the reefs by 

 wave action. 



It is, I think, well to consider the bearing of recent work upon 

 these different theories. The results of the Funafuti Expedition is 

 naturally of great importance. 



On the one hand, before the report on the boring was pubhshed, 

 Agassiz said {loc. cit. P. xxi., xxii.) : "The boring at Funafuti 

 reached 1114 feet. It passed at first through the modern reef rock 

 material, and below that must have, judging by analogy, penetrated 

 either an underlying mass of tertiary Umestone, or have passed 

 through the mass of modern reef rock forming the outer talus of the 

 atoll of Funafuti." 



On the other hand, Dr. Hinde, who examined and identified 

 the organisms contained in the bore, says in the Report, p. 334 : 

 " Although there are considerable differences in the character of 

 the rock in different parts of the main boring, the evidence appears 

 to me to indicate a continuous formation of reef rock without any 

 abrupt break from 1114 feet to the present day." 



P. 319 : " It seems highly probable that the corals all belong 

 to well known genera of reef building-corals, and most of the species 

 appear to be closely allied, if not the same as the species already 

 described." 



P. 316 : " The various organisms from the borings all belong 

 to existing genera, and with some exceptions the species so far as 

 they can be determined are still hving. The greater number have 

 been recognised in the dredgings from the outer slope of the reef 

 and from the lagoon, and in the collections made on the reef at 

 Funafuti. Some, however, have not been met with in the recent 

 fauna of the locaUty." 



This appears to me to entirely negative the predictions made by 

 Agassiz and to justify the statements made by Sollas that the boring 

 did not penetrate tertiary limestone, and that throughout it consisted 

 of reef material with corals growing in situ. " Age of the Earth," 

 p. 130. 



Wood- J ones, however, still maintains that the bore after 

 reaching the limit of coral growth passed through talus material 

 only. 



1 "Coral and Coral Atolls.' 



