1896 



Vernon, H. M. 1895. 



The respiratory exchange of the lower marine invertebrates. J. Physiol. 

 19(1-2): 18-70. 



Mereenaria (Venus) meveenaria is not mentioned, but mollusks are included 

 under "lower marine animals". Respiration is very small compared with that 

 of teleost fishes. Respiratory activity of different animals is affected 

 very differently by temp. The less differentiated and lower forms show 

 greatest effects. Small animals have higher respiration rates than larger 

 animals of the same species. In captivity, respiration of mollusks remained 

 either constant or diminished slowly with time. On asphyxiation, quotients 

 greater than unity were obtained. - J.L.M. 



1897 



Verrico, Donald J. 1972. 



The abundance of the hard clam, Meroenaria (=Venus) mercenaria, in relation 

 to substrate character in South Oyster Bay, New York. A thesis presented to 

 the faculty of Hofstra University in partial fulfillment of the requirements 

 for the degree of Master of Arts, 27 p., some not numbered. 



The author recognized 4 bottom types: very soft mud with little vegetation; 

 firm bottom lacking vegetation; eelgrass beds; and edges of channels where 

 sediments were relatively coarse. Average densities of clams were 0.58/yd2 

 in soft mud, 1.21 in sand, 1.41 in eelgrass beds, and 0.63 at edges of 

 channels. All the mean values for particle size fell within the range for 

 fine sand, thus the survey was not very sensitive to the relationship of 

 clam abundance to particle size. The bottom in the soft mud area was a 

 reducing environment, not favorable for clams. The firm sandy bottom 

 contained the smallest clams, which is consistent with its intensive use 

 as a clamming area. Eelgrass beds and channel edges had the largest clams, 

 and these are not heavily harvested. The author concluded that clam 

 density was inversely related to particle size, but that presence of H2S 

 disturbed the relationship, and that presence of eelgrass is important to 

 hard clam because it provides a substrate for setting, recycles nutrients, 

 prevents production of H2S, reduces current velocity thus favoring setting, 

 and inhibits harvesting by humans. (Abstracter's note: the author's 

 conclusions are not well supported by his data, and appear to be taken 

 mostly from the literature. Alternative conclusions might be drawn, and 

 more conclusions might be possible if detailed data were included. For 

 example, only average sizes of clams per sample are given and numbers of 

 clams are not included. Information on particle sizes is much more 

 detailed.) - J.L.M. 



1898 



Verrill, A. E. 1873. 



VIII. - Report upon the invertebrate animals of Vineyard Sound and the 

 adjacent waters, with an account of the physical characters of the region. 

 In Report on the condition of the sea fisheries of the south coast of 

 New England in 1871 and 1872. Spencer F. Baird, Commissioner. U.S. Comm. 

 Fish Fisheries, Washington, Govt. Printing Off.: 295-522. 



Venus meveenaria is common on sandy shores, living chiefly on sandy and muddy 

 flats just below low water, but often found on the portion laid bare at low 

 water of spring tides. It most abounds in estuaries. It burrows a short 

 distance below the surface, but is often found crawling at the surface, with 

 the shell partly exposed. It has short siphon-tubes, united from base to 

 near the ends, and a large muscular foot with a broad thin edge. Mantle 

 lobes are separate all around the front and ventral edge of the shell, and 

 their edges are thin, white, and folded into delicate frills, some of which, 

 near siphons, are elongated. The broad opening in the mantle allows the foot 

 to be protuded from any part of the ventral side, with an extensive sweep 

 forward and backward. Foot and mantle edges are white, tubes are yellowish 

 or brownish-orange toward the end, more or less mottled and streaked with 



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