Before submerging monthly collecting panels it may be well to get 

 a vertical picture of shipworm distribution for the locality by using a 

 Special Collecting Board. This is nothing more than a long strip of wood 

 which extends from the mud line to high water, from which it is possible 

 to learn the exact depth at which the borers are most active. While this 

 is usually near the mud line, there are many exceptions and sometimes the 

 attack is more severe at the surface. 



The laminated collecting board is actually a trap for catching specimens 

 and is used mainly for obtaining specimens for taxonomic studies. The 

 board is made up of 6 or more layers of soft, straight-grained wood 12 x 6 x 

 V2 inches with brass or galvanized iron washers separating the layers, to 

 produce cracks large enough so that the shipworms will not cross from 

 one layer to the next. Consequently the borers form long straight tubes 

 and, as the wood is thin, they are easily extracted. The laminated collecting 

 board should be suspended in the region of most severe attack, usually 

 near the mud line. It should be examined every 2 weeks in warm or tropical 

 waters, where destruction is more rapid and removed for study when the 

 attack has progressed sufficiently. 



The best specimens are obtained if the animal is dissected out as 

 soon as the board is removed from the water, or, if this is impossible, 

 the board should be submerged in 70 percent alcohol for a week and then 

 shipped to the laboratory wrapped in a cloth saturated with alcohol. Once 

 the specimens have been extracted from the wood they should be preserved 

 in a mixture of 4 parts alcohol (70 percent) and one part glycerine. This 

 keeps the periostracal margin of the pallets soft and pliable and, should the 

 alcohol evaporate, the glycerine will keep the pallets moist for some time. 

 The shells and pallets of each specimen should be kept together in a vial 

 and all the specimens from one board should be given the same number. 



Permanent slides, for ease in studying the pallets under the microscope, 

 may be made by mounting the pallets in "Diaphane." They may be 

 mounted directly from glycerine-alcohol, or, if fresh specimens are used, the 

 pallets should be put in 75 percent alcohol for at least 24 hours. Magnifi- 

 cation of 10 to 24 diameters is sufficient for identification in most cases. 



Ecologists interested in other marine organisms such as algae, encrust- 

 ing and filamentous bryozoans, tunicates, barnacles, and such mollusks as 

 Anomia, Ostrea, and Mytilus, may find the use of these collecting boards 

 easily adapted to their needs. A checklist of the specimens removed from 

 the surface of panels over a period of a year includes many species in all 

 of these groups. 



REFERENCES 



ATWOOD, W. G. and JOHNSON, A. A., 1924. Marine Structures, their Deteriora- 

 tion and Preservation. Nat'l. Res. Council, Washington, D. C. (Biological section, pp. 

 6-76, 12 plates, by W. F. Clapp, C. A. Kofoid, and R. C. Miller). 



BARTSCH, P., 1922. A Monograph of the American Shipworms. Bull., U. S. Nat'l. 

 Museum, No. 122, pp. 1-48, 37 plates. 



CLENCH, W. J. and TURNER, R. D., 1946. The Genus Bankia in the Western 

 Atlantic. Johnsonia 2, pp. 1-28, pis. 1-16. 



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