100 



80 



X 



O 



>- 



Q 60 



O 



z 

 < 



O 40 



z 

 < 



6 



a, 

 20 



Diopatra 



\- 



I 



Amphitrite 



cuprea (39) 



ornata (37) 



Arabella iricolor (7) 



■I 



Nereis sp. (6) 



Morphysa sp. (6) 



Giycero dibronchiata (22) 



1,000 



2,000 3,000 



/jG. iron / G. DRY WEIGHT 



4.000 



5.000 



Figure 17. — Relation between concentrations of manganese and iron in six species of polychaetous worms. Each value is 

 represented by the mean and standard deviation of the number of samples indicated in parentheses. Each sample con- 

 sists.of about 10 worms. 



determining the elemental content of poly- 

 chaetes. Samples of sediment from each sta- 

 tion are being analyzed for concentrations of 

 zinc, manganese, and iron. 



Our data suggest that the mechanism of ac- 

 cumulation of manganese and iron might dif- 

 fer from the mechanism of accumulation of 

 zinc. The apparent inverse relation between 

 levels of zinc and iron in polychaetes has been 

 reported elsewhere in the literature and at- 

 tributed to feeding type. At present, our data 

 do not support this hypothesis entirely; more 



data are needed before any definite conclusions 

 can be reached. 



These preliminary results suggest that the 

 concentrations of trace elements in polychaetes 

 are intimately associated with the geochemistry 

 of these elements. We are continuing our stud- 

 ies of the zinc, manganese, and iron concen- 

 trations in polychaetes in relation to the total 

 movement of these elements in the Newport 

 River estuary. In addition, we are includ- 

 ing several other trace elements in our analy- 

 ses. 



34 



