386 SCIENCE PROGRESS. 



by the CJuille^iger Expedition from the intermediate depths 

 appear to have a much wider horizontal distribution than the 

 surface fauna, and that they obtain their food by the capture 

 of the dead organisms continually falling from surface to 

 bottom. Agassiz will certainly have some difficulty in 

 meeting his final argument. "It is well known that the 

 deposits at the bottom are in most regions chiefly made up 

 of the dead shells and skeletons of surface organisms. We 

 have no definite ideas as to the rate at which these surface 

 creatures may be falling- to the bottom, but it is evident 

 that nets which have been dragged in these intermediate 

 depths on the opening and closing principle, without captur- 

 ing any of these falling organisms, have either not been 

 dragged for a sufficiently long time and through a sufficiently 

 great extent of water, or have not worked successfully." 

 Those who have not themselves invented opening and 

 closing tow-nets, but who have yet worked with them, will 

 recognise the force of the last four words. 



The exploration of the sea has proved to be of exciting 

 interests to geologists. The mere mention of the subject 

 of the ." permanence of continents " causes angry passions 

 to rise. It is more than probable that there are yet "crowns 

 to be broke " over this momentous discussion. L. Agassiz 

 thought, so long ago as 1869, that the present continental 

 areas within the 200 fathom line, as well as the oceans, 

 have preserved their outlines and positions from the earliest 

 times; that they have "remained essentially the same 

 through all geological ages, varying only as to their relative 

 height and depth as well as to their respective extension ". 

 Passing over the passionate utterances of geologists, which 

 may have all the value claimed for them, we get now the 

 testimony of this other great explorer of the deep sea. Dr. 

 John Murray contends that : "It is most probable that the 

 Ocean Basins were not so deep in these early ages, and 

 numerous islands probably existed in them, with rocks 

 similar to those that now make up the bulk of continental 

 land. Possibly these former land-masses now form the 

 submerged bases of the groups of oceanic islands wholly 

 consisting, so far as we can see, of erupted rocks. In the 



