1 64 HIDDEN BEAUTIES OF NATURE 



coral reefs Darwin's theory receiving the more gen- 

 eral support. But whatever question may be raised 

 as to the 'gradual sinking' theory, or the 'elevating' 

 or other theories, there can be no question as to the 

 beauty of the teeming life in the clear waters about 

 the Australian Barrier Reef. We are acquainted 

 with the madrepores and other corals only in the 

 shape of dry skeletons, bereft of beautifully coloured 

 feelers or discs, which in their natural element pro- 

 trude from every one of the innumerable mouths or 

 openings on the surface of the coral rock, and which 

 give the sea pools the appearance of a marine flower 

 garden. 



The corals sent home from this remarkable reef by 

 Mr. Saville Kent may be seen in the Cromwell Road 

 collection, and on the adjoining walls are photo- 

 mezzotypes of the seascapes along the direction of 

 the reef. His famous book on this subject is the best 

 monograph on corals ever produced. 



We must note one or two more points in the history 

 of corals. The evidence of the principal students of 

 marine life tends to show that reef-building polyps 

 cannot live below a depth of twenty-five fathoms, or 

 one hundred and fifty feet. 



Coral polyps are extremely sensitive to atmospheric 

 action, so that ' no coral reef can grow above the 

 level of the lowest tides, and therefore all subsequent 

 additions of materials must be due to accumulation of 

 sediment transported by the action of the tides and 

 prevailing winds.' 



