56 THE BERMUDA ISLANDS. 



primarily a region of subsidence — of subsidence now actually 

 taking place, or only recently completed ; per contra, regions 

 characterized by fringing reefs are regions either of stability or 

 of slow and gradual upheaval. The greatest area of indicated 

 subsidence is that of the Central Pacific, which has been as- 

 sumed to compass a tract measuring 6000 miles in length and 

 2000 miles in greatest width. Commencing at the Paumotu 

 group, or the Low Archipelago on the south-east, and extend- 

 ing to the Carolines on the north-west, the coral structures dot 

 at intervals the surface of the sea for a linear distance of, 100 

 degrees of longitude, embracing in this, space several hundred 

 true islands, besides numerous reefs of one form or another. 

 In the Paumotu group alone there are, according to Dana, not 

 less than 80 atolls. 



The existence of such an enormous subsidence area as is in- 

 volved in the Darwinian hypothesis is necessarily difficult to 

 realize, and, indeed, numerous apparently valid objections 

 seem to interpose themselves to its full acceptance. It has been 

 shown that within, or immediately on the border of, the sup- 

 posed subsiding area there occur local tracts where fringing 

 reefs take the place of atolls; and, again, others where raised 

 coral patches or terraces clearly indicate elevation. The coral 

 on some of the Hervey and Friendly islands is stated to oc- 

 cur at a height of 300 feet above sea-level ; on the island of 

 Guan, one of the Ladrones, according to Quoy and Gaymard, 

 the coral rock is in places fully 600 feet above the sea. In 

 some island groups, as Hawai, Fcejee, etc., coral structures ap- 

 parently indicative of both depression and elevation occur 

 interassociated among the diSerent islands constituting those 

 groups, and the same feature — the iuterassociation of fringing 

 and barrier reefs with atolls — has been observed l)y Semper in 

 the Pelew Archipelago (West Pacific). This condition, together 

 with various concomitant diflBculties that lie in the way of the 

 Darwinian hypothesis, has led to the rejection by many 

 naturalists— Semper, Guppy, A. Agassiz, Murray, Geikie, and 

 others — of the subsidence-theory, and to the substitution for 



