216 



Marine Microbiology 



pelagic fertility, chiefly in the Mediterranean, but also in the 

 Indian and tropical Atlantic Oceans. The experience acquired 

 from assaying 1,210 deep water samples has convinced me that 

 the number of flagellates per liter in the aphotic zone is often 

 of the same order as, or even greater than, in the photic layer. 



These curious results seem particularly clear in the Medi- 

 terranean, where oxygen and pH show relatively high values at 

 great depths. However, some of our stations off Senegal and in 

 the central Indian Ocean are also richer below 200 m than in the 

 euphotic zone. It is not necessary to say much about the regions 

 studied, which are summarized in Table 1. 



TABLE 1 



Number of Water Samples, Preserved with Neutral Formalin, in which 



Flagellates were Counted by the Author in Several Seas, From 1936 



TO 1960 (Aphotic Layers, from 20 to 4,000 Meters). 



