308 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



southward from the reef limits, but in many places the barrier reef 

 stands not on the margin of the shelf but miles landward from the 

 edge. (See text-fig. 20.) There is also a significant terrace front 

 at depths somewhat deeper than 120 feet. These profiles should 

 be compared with those for the West Indies (fig. 11, p. 275). They 

 tell essentially the same story. The platform can not be due to the 

 presence of the Great Barrier Reef, for in many places it projects 

 beyond the reef. I state in my paper cited : 



The evidence in favor of a shore line between 25 and 30 fathoms below present sea 

 level is strong, if not conclusive, and supports the deduction that the living barrier 

 reef is growing on what was a land surface in Pleistocene time, an interpretation 

 essentially that proposed by E. C. Andrews in 1902. 1 



NEW CALEDONIA. 



I have seen no good account of the coast of New Caledonia, off 

 whose shores is one of the most important barriers known. According 

 to P. Marshall, 2 " the northeast coast is practically straight, but many 

 inlets that form excellent harbours penetrate the southwest coast." 

 The chart shows indentations in the north coast, although they are 

 not so deep as those on the south. I find references to the shore-line 

 features in two of Professor Davis's papers, 3 and from them certain 

 information may be obtained. The shore line is embayed, there 

 are deltas mostly contained in the embayments between headlands 

 that are strongly cliffed on the sea front. The present barrier reef 

 has developed subsequent to the truncation of the headlands and 

 subsequent to the submergence that has caused the embayment 

 of the coast. Just how much of the platform surmounted by the 



i W. M. Davis has published since the manuscript of this paper went to press an article entitled: The 

 Great Barrier Reef of Australia (Amer. Journ. Sci., vol. 44, pp. 339-350, Nov., 1917), in which he criticizes 

 me and others because we have not "satisfactorily explained" the origin of the form of "the continental 

 mass." Among the statements of Professor Davis is "Vaughan's view is based on the physiographic 

 investigations of parts of the eastern coast of Australia by Andrews (1903); * * *", after he had intro- 

 duced two quotations from my paper on the littoral and sublittoral physiographic features of the Virgin 

 Islands, etc., as given in abstract (Amer. Geolog. Soc. Bull., vol. 27, pp. 41-45, 1916). Professor Davis 

 has drawn an erroneous deduction regarding my cartographic studies of the Great Barrier Reef. They 

 could not have been based on Andrew's work, because Andrews neither published nor made comment 

 on a series of profiles across the Australian platform, such as those I had prepared. Furthermore, my 

 emphasis of the fact, which it seems I was the first to point out — namely, that the present Great Barrier 

 Reef in places stands some miles landward from the margin of the continental shelf— and my deduction 

 therefrom, that the platform can not be attributed to infilling behind the reef, do not warrant the inference 

 that "Vaughan * * * has excluded coral-reef agencies from any part in forming the platform itself 



* * *." I not only do not know how the Australian continental shelf was formed, but I do not know 

 how any one of a number of hypothesis can be tested. I, therefore, endeavored to confine my discussion 

 to matters on which evidence is procurable, and said nothing regarding the origin of the platform. 

 Professor Davis advances the hypothesis that the platform on which the present Great Barrier is growing 

 is a "mature reef-plain", formed in a previous physiographic cycle, and that it has been recently sub- 

 merged. Whether reefs in past geologic time formed a rampart on the edge of the Australian continenta l 

 shelf and a plain resulted from infilling behind the barrier can at present be neither proved nor disproved 

 and on this subject I have expressed no opinion. 



2 " Oceania," Handb. regionalen Geologie, vol. 7, Abt. 2, p. 23, 1912. 



3 Davis, W. M., Shaler Memorial study of coral reefs, Amer. Journ. Sci., ser. 4, vol 40, pp. 232, 233, 240 

 243,245, 270, 1915; Problems associated with the study of corals, The Scientific Monthly, vol. 2, fig. 15 on p 

 25, p. 27, 1916. 



