president's address. 837 



is curiously at variance with what Mr. Marr was saying at 

 or about the same hour of the same day in a neighbouring hall. 

 Mr. Poulton's statement is an expression of the theory of the 

 permanence of ocean basins and continental areas, and it is that 

 neither more nor less. It is desirable therefore to inquire what 

 is meant. As it stands, it is a general statement too vaguely put 

 to be of much use. Does it mean that the whole of the great 

 ocean basins and the whole of the continental areas have always 

 occupied the same relative positions ? Clearly not, for we know 

 that nearly or quite all existing land has at some time or other 

 been under the water, and there have been land connections where 

 there is now sea. The proposition must then be reduced to this, 

 that portions of the great ocean basins and portions of the con- 

 tinental areas have occupied the same relative position. In other 

 words, some portion or other of the great ocean basins has always 

 been under the water and that some portion or other of the 

 existing continental areas has always been above the sea. The 

 statement thus coi'rected is useless to us; it affords no explanation 

 of the distribution of life on the earth, for it may be true that 

 some areas of existing land and water have always been land and 

 water respectively, and yet we know that continental areas have 

 been differently divided and cut up, and the same is the case with 

 the seas. If it was intended to mean that the continents and 

 oceans had been practically the same through all time as they are 

 now, it is incorrect. For example, we have very good reason 

 from the study of the flora to believe that in Permo-Carboniferous 

 times South Africa, Southern India, Australia and South America 

 formed part of one continent, and that in the early Tertiary 

 Period North and South America were broken up into quite 

 distinct land masses, and that in the same period and earlier 

 Europe and Western Asia were indented and crossed by seas in a 

 way that would make that part of the world quite unrecognisable 

 now. 



Mr. J. E. Marr in his opening address to Section C (Geology) 

 of the British Association, 1896, says : — " We have been told that 

 our continents and ocean basins have been to a great extent 

 53b 



