associated with coarser sediments, but this does not include very coarse 

 types like gravel, rubble, and rocks. More usually are found in sand than in 

 mud. Over the whole area it was estimated that the standing crop was 

 847,324,000 hard clams of all sizes. (Abstracter's note: this was about 

 22,018 clams/acrej Heavy densities of 'large clams probably are caused by 

 the preference for small clams, which allows larger sizes to accumulate. 



Tables 1 & 2 are reproduced here to give details: 

 Number per ft2 

 Sublegal Necks Large Broken Total 



Providence River 0.18 0.90 0.47 0.02 1.57 



Ohio Ledge 0.05 0.16 0.25 0.02 0.48 



East Passage 0.05 0.09 0.08 0.01 0.23 



Bristol Harbor 0.15 0.34 0.35 0.02 0.86 



Mount Hope Bay 0.05 0.08 0.13 0.01 0.27 



High Banks 0.02 0.05 0.25 0.03 0.35 



Greenwich Bay 0.07 0.07 0.14 0.01 0.2 9 



Upper Bay (av) 0.07 0.19 0.21 0.02 0.49 



Estimated 

 total no 

 of clams 



325,593 



195,562 

 56,217 

 65,898 



106,373 

 67,619 

 30,062 



847,324* 



*Total number. Numbers are in thousands. Totals and totals 

 per unit area are not proportional because regions are not 

 equal size. 



J.L.M. 



1871 



U.S. Public Health Service. 1954. 



A report on the public health aspects of clamming in Raritan Bay. 



Could not locate. See Campbell 1964, 1965. - J.L.M. 



1872 



U.S. Public Health Service. 1961. 



Transcript of conference on pollution of the interstate waters of the 

 Raritan Bay and adjacent waters, First Session. August 1961. 



Could not locate. See Campbell 1964, 1965. - J.L.M. 



1873 



Uzmann, Joseph R. 1955. 



Parasites of clams. 5th Ann. Conf . on Clam Research, Boothbay Harbor, Me. 

 U.S. Dept. Interior, Fish Wildl. Serv.: 71. 



The following parasites were found on Venus: the nemertean l-lalacobdella 

 obesa and the trematode Rimasthla quissetensis . - J.L.M. 



1874 



Valiela, Ivan, Mario D. Banus, and John M. Teal. 1974. 



Response of salt marsh bivalves to enrichment with metal-containing sewage 

 sludge and retention of lead, zinc and cadmium by marsh sediments. Environ. 

 Pollut. 7(2): 149-157. 



Growth of Mercenaria mereenaria and American oyster was not affected by 

 experimental additions of sewage sludge containing Pb, Zn, and Cd, but 

 Modiolus demissus grew better than controls. No increase of Pb or Zn content 

 occurred in any of the 3 species, but Cd increased in all. Apparently Pb and 

 Zn were largely trapped by marsh sediments. Cd was also retained by sediments 

 but it was more labile. - J.L.M. 



520 



