be read. This abstract discusses only direct references to M. meroenaria, 



- J.L.M. 



2107 



Deaton, L. E.,and M. J. Greenberg. 1978. 



Systematic distribution of the ionic dependence of the action potentials of 

 bivalve hearts. Am. Zool. 18(3): 641 (abstract 408). 



The action potential (AP) of the bivalve heart has been shown to depend pri- 

 marily on Na in Meroenaria meroenaria, of the Subclass Heterodonta. They 

 examined 25 freshwater and Atlantic and Gulf of Mexico coasts species be- 

 longing to the Subclasses Pteriomorphia, Heterodonta, and Paleoheterodonta 

 to determine correlations between ionic dependence of the AP and Subclass. 

 Ventricles from all Heterodont and Paleoheterodont tested beat in Ca-free 

 but not Na-free seawater (SW) . The data suggest that the APs of pteriomorph 

 hearts are dependent primarily on Ca and those of heterodont and paleoheter- 

 odont hearts depend on Na. - modified authors' abstract. - J.L.M. 



2108 



Deaton, Lewis E.,'and Michael J. Greenberg. 1980. 



The ionic dependence on the cardiac action potential in bivalve molluscs: 

 systematic distribution. Comp. Biochem. Physiol. 67A(1): 155-161. 



Meroenaria meroenaria hearts are insensitive to ouabain but stop beating im- 

 mediately in Li seawater. The sodium channels in M. meroenaria hearts (and 

 those of other venerid species) may be much less permeable to Li than the 

 Na channels of other bivalve hearts. Oysters and mussels belong to the 

 bivalve subclass Pteriomorphia. Isolated ventricles from these species beat 

 in Na-free seawater, but in Ca-free seawater all electrical and mechanical 

 activity ceases, although in C. gigas and G. demissa modified action poten- 

 tials can continue. The clams Maorooallista nimbosa, Meroenaria meroenaria, 

 and Spisula solidissima have ventricles that beat in Ca-free seawater but 

 not in Na-free seawater. The results of this study suggest that this dif- 

 ference has a systematic correlation. - J.L.M. 



2109 



DiGirolamo, Rudolph, John Liston, and J. Matches. 1977. 



Ionic bonding, the mechanism of viral uptake by shellfish mucus. Applied 

 Envir. Microbiol. 33(1): 19-25. 



The process involves attachment of viruses to mucus secreted, and then 

 ingested, by Meroenaria meroenaria and other bivalves during feeding. 

 Analysis of the mucus-virus bond indicated that attachment of virus to 

 mucus is primarily ionic and involves binding of viral particles to sulfate 

 radicals on the mucopolysaccharide moiety of shellfish mucus. - modified 

 authors' abstract. - J.L.M. 



2110 



Dugas, Ronald J. 1980. 



A status report on commercial clamming efforts in Louisiana. La. Dept. 

 WildL. Fish., Contr. Mar, Research Lab. - 1978. Mar. Research Lab., 

 Grand Terre Island, La., Tech. Bull. 31: 23-32. 



Following a brief review of pertinent aspects of the biology of Meroenaria 

 sp. there follows a review of exploratory fishing results for M. oampeohensis. 

 The area covered Breton and Chandeleur Sounds. There were significant and 

 harvestable populations of chowder size M t oampeohiensis east of the Missis- 

 sippi River, but there is no real demand for these large quahogs. The rapid 

 growth rate in the south makes littlenecks and cherrystones available to 

 harvesters for a relatively short time, and the presence of large clams 

 probably inhibits development of large numbers of young. Managerial recom- 

 mendations include a number of alternatives including the advisability of 

 designating public and private grounds, considerations of limited entry and 

 quotas, and a variety of other options. - J.L.M. 



586 



