DIATOMS: The accumulated total of several species 

 of diatoras is represented in figure 16. The highest con- 

 centration was present near the bottom at 2400 6 July. From 

 this point the concentration decreased toward the surface to 

 8 cells per ml at 35 feet between 1800 6 July and 0600 7 July. 

 In general, the distribution of diatoms was limited to water 

 which showed 60-percent light transmission or higher. 

 Diatom blooms characteristically occur in the spring in 

 these waters. It is believed the low concentrations found 

 represented the frustules of dead cells, the remnants of 

 previous blooms. Their presence in low numbers made no 

 apparent contribution to light attenuation. 



1800 



2200 



0200 0600 



TIME (HOURS) 



1000 



1400 



Figure 16. Distribution of miscellaneous diatoms (organisms per ml), with 

 transparency data (percent transmission) in red. Operation I. 



33 



