166 Marine Microbiology 



terial zone, which coincides with the pelagic zone, varies some- 

 what in depth and at night generally rises to the surface as can 

 be obsened by the fluorescent light emission of many of the 

 plankton. If the electromagnetic force on the bacteria varies with 

 the surface current and current gradient, one would expect the 

 bacteria zone to vary; and also at night when the surface wind 

 and current velocity are generally low, the zone would be ex- 

 pected to approach close to the surface. Heretofore, the fact that 

 the bacterial zone coincides closely with the pelagic zone has 

 been explained as due to the attachment of the bacteria to plank- 

 tonic organisms. It appears that the electromagnetic force on 

 these particles is large enough to bring about a similar distribu- 

 tion pattern. 



The very large bacterial enrichment in the bottom muds 

 especially near shore can also be explained by this mechanism. 

 Under conditions of high wind velocity and thus higher surface 

 currents, the radius of curvature of particles can increase greatly. 

 The enriched zone of bacteria will then be depressed and from 

 Figure 2 it can be seen that it is entirely feasible that the zone 

 may come in contact with the bottom. The organisms will then 

 be trapped and as the bottom silts present a large surface area 

 for attachment, they will ultimately be localized on the ocean bot- 

 tom. The extremely large bacterial population in the top few cen- 

 timeters of bottom muds is well known and appears adequately 

 explained by this hypothesis. 



It appears therefore that masses of colloidal size carrying 

 single or multiple charges up to masses of the size of marine bac- 

 teria carrying thousands of electron charges have the appropriate 

 charge to mass ratio to account for a surface to bottom charge 

 separation in the ocean of equatorial regions and the known ver- 

 tical bacterial distribution in the sea. It is apparent that once such 

 carriers reach the vicinity of the ocean floor they are essentially 

 trapped in this region. If local currents carry them up from the 

 bottom they soon are caught in the prevailing bottom currents 

 which, being at right angles to the horizontal component of the 

 earth's magnetic field, will return them to the bottom. It may 

 well be that the iron and manganese which may be precipitated 

 by bacteria (4) near the ocean bottom are directly connected 



