250 



STATION NUMBER 

 252 



254 



4 5 

 MILES FROM MAUMEE RIVER 



Fig. 18--Avera»:e aburdarce of phytoplanktor groups, and of albuminoid 

 and free amraoria, in the Waunee Bay SectiO" In July, August, 

 and September, 1930. Each polrt represents the averape of 

 six determi rations . Data taken from ToMes 33, 56, 5?, 

 and 58. 



190 



