health. In 1966 New York began a program to transplant shellfishes from 

 polluted Jamaica Bay, Long Island to clean waters. - J.L.M. 



1922 



Wallace, David H. 1971. 



The biological effects of estuaries on shellfish of the Middle Atlantic. 

 In A Symposium on the Biological Significance of Estuaries. P. A. Douglas 

 and R. H. Stroud (eds.) . Sport Fish. Inst., Washington, D.C.: 76-85. 



Hard clam, living in lower parts of estuaries, are far more adjustable than 

 oyster to environmental deterioration. In heavily contaminated Raritan Bay 

 hard clam still spawn and reproduce successfully, although oyster is long 

 since gone. The standing hard clam population is several million bushels, 

 but these are unsafe for eating raw. Intensive policing is necessary to 

 prevent marketing. Conditions are similar in various places in the 

 Mid-Atlantic states. The recent rise in production of hard clam in New York 

 was- made possible by a series of excellent sets in several bays on the 

 south shore of Long Island. - J.L.M. 



1923 



Walls, R. A., Paul C. Ragland,and Edward L. Crisp. 1977. 



Experimental and natural early diagenetic mobility of Sr and Mg in biogenic 

 carbonates. Geochim. Cosmochim. Acta 41(12): 1731-1737. 



Ammonium acetate dissolution experiments on shell material of Crassostrea 

 virginica (calcite) and Mercenaria mercenaria (aragonite) suggested the 

 following relative order of abundance for readily exchangeable Sr and Mg: 

 Mg (arag) >Mg (calc) >Sr (calc) >Sr (arag) . Preferential dissolution of Mg and Sr 

 with respect to Ca can be explained by the presence of loosely bound ions 

 in a multi-phase shell structure. - J.L.M. 



1924 



Walne, P. R. 1958. 



The importance of bacteria in laboratory experiments on rearing the larvae 

 of Ostrea edulis (L.). J. Mar. Biol. Assn. U.K. 37(2): 415-425. 



Mercenaria (Venus) mercenaria is not mentioned. - M.W.S. 



1925 



Walne, P. R. 1964. 



The culture of marine bivalve larvae. Chapter 6 in Physiology of Mollusca. 

 Vol. 1. Karl M. Wilbur and C. M. Yonge (eds.). Academic Press, New York: 

 197-210. 



Carriker (1959) studied for 3 yrs a pond in Long Island Sound. Venus grew 

 well but rate of exchange with the sea was so high that few larvae were 

 retained. Author stresses the importance of controlling bacteria in larval 

 cultures. Not all batches of eggs from one Venus had the same vitality. 

 There is no greater variation in survival and growth of larvae of young or 

 old parents than between different members of the same age group. Chanley 

 (1955) found that Venus larvae from same female crossed with 2 different 

 males, and from 2 females crossed with the same male, showed significant 

 differences in growth rate, suggesting that inherited factors from either 

 parent were responsible. This needs further investigation. Annual cycle of 

 activity of hard clam gonads is: 1) resting phase - resorption of unspawned 

 material may take place; 2) phase of active gametogenesis , giving ripe 

 oocytes and spermatozoa; and 3) liberation of sex products, which requires 

 a stimulus. Resting period is often a period of rapid growth and 

 replenishment of food reserves, and it is useless to attempt to condition 

 for spawning at this time. Once sufficient reserves have accumulated, the 

 period required for maturation of gametocytes is a function of temp. Raising 

 water temp, to 20-22°C over 2-3 wks is sufficient for V. mercenaries, 

 although behavior is less predictable than that of Crassostrea virginica. 

 V. mercenaria is more resistant than Crassostrea to stimulation by presence 

 of egg or sperm. It is best to use gametes which have been shed by the 



534 



