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THE 



AMERICAN JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



Art, XXIY. — Origin of Coral Reefs and Islands ; by James D. 



Dana. 



[Continued from page 105.] 



Part II. The Objections considered. 



The objections to the Darwinian theory may be considered 

 in the following order: 



I. Darwin's insufficient knowledge of the facts bearing on the 

 subject. 



II. Subsidence not ordinarily a fact because methods of produc- 

 ing barrier reefs and atolls have been brought forward that do 

 not require its aid. 



III. The occurrence of cases of elevation in regions of atolls 

 and barrier reefs inconsistent with the subsidence-theory. 



IY. No ancient coral reefs in the geological series have the 

 great thickness attributed by the subsidence-theory to modern 

 reefs. 



Y. Other methods of explanation and their supporting evidence. 



The adverse remarks directed against the idea of a sinking 



continent in the Pacific as the initial condition in the coral-reef 



subsidence are outside of the present discussion for the reason 



stated on the first page of this paper. In the following pages 



the objections are first explained, under the above-mentioned 



heads, and then follow, in paragraphs lettered a, b, c, etc., the 



writer's discussions of the several points. 



Am. Jour. Sci.— Third Series, Vol. XXX, No. 111.— Sept., 1885. 

 11 



