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V. NOTICES OF NEW BOOKS. 



I. The Structure and Distribution of Coral Reefs ; being 

 the first Part of the Geology of the Voyage of the Beagle under 

 the Command of Capt. Fitzroy, R.N. during the Years 1832 to 

 1836. By Charles Darwin, M.A., F.R.S., Naturalist to the 

 Expedition. London, pp. 214. 1842. 



Mr. Darwin, in addition to his journal of the voyage of the 

 Beagle, has since published, with the approval of the Lords Com- 

 missioners of the Treasury, two volumes having reference to 

 geological subjects — the results of investigations made during his 

 expedition. 



It is to be regretted, that the publication of these volumes was 

 delayed in consequence of the ill health of the author, which 

 long prevented the close attention necessary to prepare his ob- 

 servations for the press. "We have reason to rejoice that the 

 works themselves require no apology for the state in which they 

 appear. 



The object of the volume at present before us, is to describe in 

 detail the general structure and the circumstances of formation of 

 coral reefs, with the object of explaining and supporting certain 

 views of the action of disturbing forces, assumed by the author to 

 have produced elevations and depressions of the sea bottom, and 

 in this way accounting for many geological phenomena in different 

 parts of the world, and of various periods. 



There are two great classes of coral-reefs, in one or the other 

 of which the whole number may be included: those, namely, 

 which exhibit near the surface no evidence of any solid rock 

 from which they may have originated — the barrier and atoll- 

 formed reefs, and those which are called fringing -reefs — where, 

 owing to the nature of the slope and the vicinity of land, there 

 can be no doubt as to the origin. The former class (including 

 the lagoon islands) have attracted most attention, and offer the 

 most striking phenomena, but both of them are extremely 

 interesting. 



The term " atoll " is used by the inhabitants of the islands in the 

 Indian ocean to distinguish circular groups of coral islets some- 

 times called " Lagoon islands," a kind of salt-water lake or lagoon 

 being often formed by a nearly continuous curved line of such 

 reefs, only leaving one or two outlets. Barrier-reefs are little 

 less marvellous in their structure than the atolls, the band of 

 coral-reef sometimes forming a fringe of land, while sometimes 



