TRUE THEORY OF CORAL REEFS, 317 



its inclination. Deep holes and ravines, fall, per- 

 haps, of fresh water, may have existed on the old 

 land, so that when the surface of these lakes and 

 hollows first sank to the surface of the sea, and 

 admitted its waters, the bottom may have been too 

 deep for the coral animals to live on. This would 

 explain such a phenomenon as the deep narrow 

 channel just north of Sir C. Hardy's Islands, with 

 reefs running along each side of it. In short, every 

 modification in the form and structure of the reefs 

 is explicable by this hypothesis, and many difficulties 

 solved, which admit of no other explanation. 



It may seem uncalled for in me thus to thrust 

 forward my opinion of Mr. Darwin's work ; but 

 after seeing much of the Great Barrier reefs, and 

 reflecting much upon them, and trying if it were 

 possible by any means to evade the conclusions to 

 which Mr. Darwin has come, I cannot help adding 

 that his hypothesis is perfectly satisfactory to my 

 mind, and rises beyond a mere hypothesis into the 

 true theory of coral reefs. 



If the fact of depression of the north-east const daring the 

 formation of the great coral reefs be held u proved, it follows 

 that, during the early part of the period of their formation,Torrcs 

 Strait, and the shoal seas on each side of it, were dry land, and 

 Australia connected to New Guinea. This would explain, per- 

 haps, the fact of the marsupial type of animals being common to 

 both, though the genera and species are different. It would ex- 

 plain also the difference in the assemblage of shells, etc. on the 



