(Abstracter's note: The exact source of this reprint was not known.) - D.L. 



443 



Davis, Harry C ., and Anthony Calabrese. 1964. 



Combined effects of temperature and salinity on development of eggs and 

 growth of larvae of M. mercenaria and C. virginica. U.S. Dept. Interior, 

 Fish Wildl. Serv. , Fish. Bull. 63(3): 643-655. 



Clam larvae can ingest foods at significantly lower temps than the minimum 

 temp at which they can digest and assimilate food organisms used in these 

 experiments. They can digest and assimilate naked flagellates such as 

 Monochrysis lutheri and Isochrysis galbana at lower temps than those at 

 which they can utilize algae with cell walls, like Chlorella sp. Minimum 

 temp for appreciable growth of clam larvae fed naked flagellates was 

 12.5°C. Optimum salinity for growth of clam larvae was 27°/°° (the 

 highest salinity tested) or possibly higher. There was no well-defined 

 optimum temp for growth of clam larvae at any salinity; maximum growth 

 occurred at temps from 25 to 30°C in almost all salinities. Effect of 

 reduced salinity on clam larvae was to reduce range of temp tolerated. 

 Effect on clam larvae was primarily a reduction of the range of temp 

 tolerated, by heavy mortality at high temp. - modified authors' summary 

 - J.L.M. 



444 



Davis, H. C, and P. E. Chanley. 1956. 



Spawning and egg production of oysters and clams. Biol. Bull. 110(2): 117-128. 



Hard clams were induced to spawn in the laboratory. The total number of eggs 

 released by an individual female ranged from 8 million to 39.5 million and 

 averaged 24.6 million eggs per clam. The most eggs released by a female at a 

 single spawning was 24.3 million eggs. Correlation between eggs produced and 

 shell cavity volume was 0.38 (significant at 0.05 level). Clams spawned at 3-, 

 7-, and 14-day intervals showed no significant difference in average number of 

 eggs released in a season and no difference in number of spawnings per female. 

 The correlation between number of times a female spawns and the number of eggs 

 produced was about zero. - D.L. 



445 



Davis, H. C, and P. E. Chanley. 19 56. 



Spawning and egg production of oysters and clams. Proc. Natl. Shellf. Assn. 

 46: 40-58, plus tables and illustrations on unnumbered pages. 



Three groups of Mercenaria mercenaria were induced to spawn in the laboratory 

 at 3- 7-, and 14-day intervals. There was no significant difference in total 

 numbers of eggs released (number after spawning could no longer be induced) by 

 clams in the 3 groups, nor any significant difference in average number of 

 spawnings/female. Total numbers of eggs released by female clams ranged from 

 8 million to 39.5 million and averaged 24.6 million/clam. The highest number 

 released by any clam at a single spawning was 24.3 million eggs. Correlation 

 between number of eggs produced and shell cavity volume was 0.38 (P=0.05). 

 There was no correlation between number of times a female clam spawned and 

 number of eggs produced. - modified authors' summary. - D.L. and J.L.M. 



446 



Davis, H. C, and P. E. Chanley. 1956. 



Effects of some dissolved substances on bivalve larvae. Proc. Natl. Shellf. 

 Assn. 46: 59-74. 



Growth and survival of Mercenaria mercenaria larvae were not affected by 

 addition of Vitamins A and B12 , biotin, calcium pantothenate, nicotinic acid, 

 pyridoxine hydrochloride, riboflavin, thiamine hydrochloride separately, or by 

 calcium pantothenate, pyridoxine hydrochloride, riboflavin, and thiamine 

 hydrochloride in combination, although oyster larvae treated similarly grew 

 faster than controls. Clam larvae survived at least 6 days in 1/100,000 CuS04 , 

 but oyster larvae were killed by concentrations of less than 1 ppm. The 



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