ARTICLES 421 



Hedley, and Taylor of Sydney, New South Wales, had confirmed 

 this inference by observations early in the 1900's on the coast 

 itself ; Marshall of Dunedin, New Zealand, similarly interpreted 

 the embayments of certain barrier-reef islands that he visited 

 a few years later in the central Pacific ; and Vaughan has in 

 recent years called attention to the embayments of reef-bordered 

 coasts in the West Indies. 



At an earlier date Crosby had noted the association of 

 " half-drowned valleys " with the coral reefs of Cuba (1884) ; 

 and Bonney had briefly called attention to the support given 

 by embayments to the theory of subsidence, in the supple- 

 mentarypages which he appended to the third edition of Darwin's 

 Coral Reefs (1889). Nevertheless, the pertinence of Dana's 

 evidence for Darwin's theory had gained no general recognition ; 

 I therefore prepared an article emphasising the value of" Dana's 

 principle," and published it in the American Journal of Science, 

 with which he had long been associated as editor, on the cen- 

 tenary of his birth. 1 



Exclusion of Still-stand Theories. — A year later the unex- 

 pected opportunity came to me of making a voyage across the 

 Pacific, for which generous subventions were provided by the 

 Shaler Memorial Fund of Harvard University and by the British 

 Association for the Advancement of Science, whose meeting 

 i in Australia I attended ; thus some thirty reef-encircled islands, 

 1 as well as a long stretch of the Queensland coast inside the 

 Great Barrier Reef of Australia, were briefly examined. In 

 every case, the embayed shorelines of the mountainous islands 

 within the barrier reefs proclaimed submergence. Furthermore, 

 an examination of many barrier-reef charts shows that the 

 embayment of the central islands is a universal characteristic. 

 Hence all still-stand theories, which postulate a fixed relation 

 between reef foundation and ocean-level, are disproved for 

 barrier reefs ; and as atolls resemble barrier reefs in all respects 

 except in not having any central islands, the still-stand theories 

 are made, to say the least, extremely improbable for atolls also. 

 Reef upgrowth thus appears to be intimately associated 

 with submergence whenever the matter can be tested ; and 

 hence, if submergence could be caused only by subsidence, 

 Darwin's theory of reef upgrowth during the intermittent sub- 



1 "Dana's Confirmation of Darwin's Theory of Coral Reefs," Amer. Journ. Sci, 

 xxxv. 1913, 173-188. 



