1878 



Van Weel, P. B. 1961. 



The comparative physiology of digestion in molluscs. Am. Zool. 1(2): 245-252. 



Not much is known about many aspects of digestion in mollusks, practically 

 nothing of permeation through the intestinal wall. What is the correlation 

 between "willingness" to phagocytize and true resorption? Does the midgut 

 gland "take over" from the intestine, or vice versa? What are the causes of 

 apparent changes in resorption and enzyme production from drastic changes in 

 diet? Is there adaptation in the long run? Definite data are lacking on the 

 relation between utilization and amount of food available. How does age affect 

 enzyme production, resorption and utilization? These problems await solution. 

 Mercenaria (Venus) mercenaria is not mentioned but these questions are 

 applicable. - from author's conclusions - M.W.S. and J.L.M. 



1879 



Van Winkle, Webb. 1966. 



Gill tissue respiration as a function of salinity and temperature in four 

 species of pelecypods. Proc. Natl. Shellf. Assn. 56: 6 (abstract). 



Oxygen consumption (Q02) or excised gill tissue from Mercenaria mercenaria 

 was measured at salinities ranging from 5-30°/°° and temperatures of 10°, 

 18°, and 26°C. The Q02 was significantly higher at the lower salinities, 

 this increase being even greater at lower temperatures. - modified author's 

 abstract - D.L. 



1880 



Van Winkle, Webb. 1967. 



Ciliary activity and oxygen consumption in Pelecypod gill tissue. Proc. 

 Natl. Shellf. Assn. 57: 5-6 (abstract). 



Cilia of gill tissue from low-salinity as compared to high-salinity acclimated 

 animals beat faster at low experimental salinities. With respect to the 

 ability of cilia to tolerate reduced salinities the 4 species are ranked as 

 follows: Modiolus>Crassostrea>Mytilus>Mercenaria. At low salinities 

 isolated gill tissue utilized as much or more oxygen than at high salinities, 

 yet at these low salinities ciliary activity was greatly reduced. If this 

 is true also in the intact animal it means that there is a constant or 

 increased expenditure of energy under conditions where the food gathering 

 machinery is working less efficiently. - J.L.M. 



1881 



Van Winkle, Webster, Jr. 1967. 



Ciliary activity and oxygen consumption of bivalve gill tissue. Ph.D. Thesis, 

 Rutgers Univ., New Brunswick, N.J. Dissert. Abstr. 28(3): 1291-B. 



Gill cilia of winter as compared to summer Mercenaria mercenaria were more 

 active at low salinities at all temps. Salinities corresponding to 80% 

 ciliary activity were 17°/°o for Mercenaria, 5°/" for Crassostrea virginiea, 

 5°/oo for Mytilus edulis , and less than 2.5°/°o for Modiolus demissus 

 plicatulus. Gill oxygen consumption was the same for low- and high-salinity- 

 acclimated Mercenaria, and was greater at low salinities. Effects of salinity 

 on oxygen consumption did not appear to be correlated with the lower salinity 

 boundaries of whole animals. Hydration and osmotic-ionic regulation theories 

 did not provide an adequate explanation of interspecific differences in effects 

 of low salinities on oxygen consumption. Effects of experimental salinity on 

 ciliary activity and oxygen consumption appeared to be independent. Ciliary 

 activity was always reduced at salinities in which oxygen consumption was 

 greater or the same. - J.L.M. 



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