CORAL REEFS AND SUBMARINE BANKS 199 
Vaughan’s latest statement to include the essential features of his 
theory of submerged platforms. All other theories are excluded 
because they fail to take account of the submergence by which the 
central islands or continental masses within barrier reefs have gained 
their embayed shore lines while the reefs grew up around them; 
by which fringing reefs and many elevated reefs have gained their 
unconformable contact with the eroded slopes that they rest upon; 
and by which, therefore, the formation of atolls also has probably 
been controlled. Hence it is desirable to examine with especial 
care the fundamental postulates and processes and the essential 
consequences of the two surviving theories with the object of 
making unprejudiced choice between them. Let it be noted, 
however, that while certain essential postulates of the two theories 
are mutually contradictory and while the conditions involved in 
them are very unlike, the processes of the two theories are by no 
means mutually exclusive; they may work together. This is 
particularly true regarding the intermittent subsidences and 
occasional uplifts of Darwin’s theory and the climatic oscillations 
of ocean-level of the glacial-control theory; their combined action 
deserves careful consideration as affording a closer approach to 
the conditions under which reefs have been formed than is provided 
by Darwin’s theory alone; and herein lies, to my mind, the chief 
value of the glacial-control theory. It is therefore unfortunate 
that so much emphasis has been placed in the latest presentation 
of the glacial-control theory upon the fundamental postulate of 
long-continued stability of the earth’s crust in those large parts of 
the Pacific and Indian oceans that are characterized by atolls, and 
upon the secondary postulate that the submergence during which 
reef upgrowth has taken place in those regions is due wholly to 
the postglacial rise of the ocean surface by about 240 feet; for 
the newest theory of coral reefs is thereby brought into unnecessary 
opposition to Darwin’s theory. 
It is my desire to make the following discussion as objective 
and impartial as possible, and to exclude from it all suggestion of 
the “warfare of scientific theories” which some of my contempora- 
ries seem to think is necessarily involved in the competitive search 
for the true explanation of a scientific problem; for it happens 
