FIG. 49 MONTHLY AVERAGES OF NITZSCHIA LONGISSIMA SETTLING AT 



SAFE HARBOR AND CONTROL STATIONS. EACH RADIUS REPRESENTS 

 - 100 SPECIMENS (A STATIONS) AND - 50 (B STATIONS) 

 READING FROM THE CENTER. 



lO*.12 



6- \^V. 



IDA 



lOB 



Each radius is numbered as the hours on a watch and represents 

 that month. 



118 



