496 THE DEPTHS OF THE SEA. [chap. x. 



of this I will quote two passages in two consecutive 

 anniversary addresses by Presidents of the Geological 

 Society, and Ave may have every confidence that the 

 statements of men of so great weight, made under 

 such circumstances, indicate the tendency of sound 

 and judicious thought. Professor Huxley, in the 

 anniversary address for the year 1870, says : — " Many 

 years ago 1 I ventured to speak of the Atlantic mud 

 as ' modern chalk,' and I know of no fact inconsistent 

 with the view which Professor Wyville Thomson has 

 advocated, that the modern chalk is not only the 

 lineal descendant, so to speak, of the ancient chalk, 

 b Lit that it remains, so to speak, in possession of the 

 ancestral estate ; and that from the cretaceous period 

 (if not much earlier) to the present day, the deep sea 

 has covered a large part of what is now the area of 

 the Atlantic. But if Globigerina and Terebratula 

 caput-serpentis and JBeryx, not to mention other 

 forms of animals and of plants, thus bridge over the 

 interval between the present and the mezozoic 

 periods, is it possible that the majority of other 

 living things underwent a sea-change into something 

 new and strange all at once ? " 



And Mr. Prestwich, in the presidential address for 

 1871, says : — "Therefore, although I think it highly 

 probable that some considerable portion of the deep 

 sea-bed of the mid- Atlantic has continued submerged 

 since the period of our chalk, and although the more 

 adaptable forms of life may have been transmitted in 

 unbroken succession through this channel, the im- 

 migrations of other and more recent faunas may 

 have so modified the old population, that the original 

 1 Saturday Review, 1858: "Chalk, Ancient and Modern." 



