818 



Hegyeli, Andrew. 1964. 



Temperature dependence of the activity of the antitumor factor in the common 

 clam. Science 146(3640): 77-78. 



Watery extracts of Meroenaria meroenarius (obviously M. meroenaria) possess a 

 factor which inhibits growth of tumors. The activity of this factor varies in 

 clams taken in different seasons from 2,800 to 3,000 retine units/kg wet 

 weight in August to 346 retine units/kg in February. High summer activity can 

 be restored in clams taken from 5°C water by holding them in warm water (e.g., 

 15.5°C or higher) for 4 weeks before preparing extracts. - J.L.M. 



819 



Heilprin, A. 1887. 



Explorations on the west coast of Florida and in the Okeechobee Wilderness. 

 Wagner Free Inst. Sci. Phila: 1-134. 



According to Hutton et al. (1956) , abstracted elsewhere in this bibliography, 

 Heilprin reported Venus oanoellata from Boca Ciega Bay, Fla. - J.L.M. 



820 



821 



Heip, Carlo. 1975. 



On the significance of aggregation in some benthic marine invertebrates. In 

 Proc. 9th Europ. Mar. Biol. Symp. , Harold Barnes (ecL) . Aberdeen Univ. 

 Press: 527-538. 



Meroenaria mercenaria is not mentioned, but several bivalve species are 

 discussed. The general principles are applicable. Most benthic marine 

 invertebrates have an aggregated spatial pattern. Some important exceptions 

 are found in bivalvia, which do not copulate, therefore do not need to 

 aggregate, and may be driven by competition for food toward a uniform 

 distribution. Pattern formation is the result of 2 opposing forces: 1) the 

 risk of not finding a partner, against the risk 2) of not finding enough food. 

 In most benthic marine invertebrate populations the strategy appears to be a 

 reduction in risk of failing to find a partner at the cost of an increase in 

 risk of not finding food. Aggregation in the species studied was not 

 mechanical, but an active process. (Abstracter's note: The literature contains 

 much evidence that M. meroenaria is not uniformly distributed. Some authors 

 have attributed this, at least in part, to the effects of environmental 

 variables, of which the nature of the substrate is an important one. On the 

 other hand, there is fairly obvious survival value in aggregation. Mass 

 spawning in an aggregated stock can be triggered by spawning of a few 

 individuals, but in sparse populations this may not happen, which could be 

 to the detriment of successful spawning and setting. That such aggregation 

 may be an active rather than a passive process, although it is not a search 

 for a reproductive partner directly in sessile bivalves, is the demonstrated 

 tendency of oyster larvae to set on living adults.) - J.L.M. 



Henderson, Jean T. 192 9. 



Lethal temperatures of Lamellibranchiata. 

 4 (25) : 399-411. 



Contr. Canad. Biol. Fish. 



N.S. 



Six Venus meroenaria were tested. Rate of heating was 0.5°C in 5 min. At 

 40°C one gaped widely and was removed from the water. At 40.5°C all gaped 

 and 2 were removed; another was removed at 41°. At 41.5° the remaining 2 

 still responded to stimulus; they were removed at 44.5 and 46°. All lived 

 except the last. The lethal point was taken to be 45.2°C. The only species 

 of 18 tested which had a higher lethal point (48.5°C) was Ostrea virginiana 

 (Crassostrea virginiea) . It was concluded that normal living temps and 

 lethal temps are positively correlated. - J.L.M. 



227 



