HILL, C. L. and KOFOID, C. A., 1927, Final Report, San Francisco Bay Marine 

 Piling Committee. (Section on Teredinidae, pp. 188-300, 51 pis., by C. A. Kofoid and 

 R. C. Miller). 



SIGERFOOS, C. P., 1908. Organization and Late Development of the Teredinidae, 

 or Ship-Worms. Bureau of Fisheries, Document No. 639, pp. 193-231, 14 pis. 



OPISTHOBRANCHS 



The most useful preservative is 70 per cent grain alcohol. Some soft or 

 gelatinous animals must be allowed to remain 2 to 6 hours in alcohol of 

 35 to 50 percent, and then transferred to that of 60 percent, and finally to 

 that of 70 percent. It is inadvisable to use formalin (5 percent) or formal- 

 dehyde, except for a few weeks in case alcohol is not immediately available. 

 An excellent and detailed account of preserving and narcotizing molluscan 

 animals is found in Part M, Bull. U. S. National Museum, No. 39 (1899), 

 "The Methods Employed at the Naples Zoological Station for the Preserva- 

 tion of Marine Animals," by Salvatore L. Bianco, translated by E. O. 



HOVEY. 



NUDIBRANCHIATA 



By G. Dallas Hanna 



Reprinted from Nautilus, Vol. 68 (3), January, 1955 



While working in southern Alaska in 1946 some experiments were 

 made in an endeavor to kill and preserve some nudibranch mollusks in a 

 fully expanded condition for Dr. F. M. MacFarland. It is well known that 

 these animals are prone to shed appendages and contract badly when 

 disturbed by the usual methods of preparation such as anesthetizing. 



One method which promised success could not be carried to conclusion 

 through lack of facilities and it was not until July 1954 that the subject 

 could be taken up again. The Arctic Research Laboratory at Point Barrow 

 offered ideal conditions in this respect and it was found that the local 

 nudibranchs which were obtained incidentally with marine geological work 

 could be killed and preserved fully expanded and with all appendages 

 intact. The method consisted of putting the specimens in a vessel of 

 normal sea water sufficient only to permit them to crawl about quietly. 

 The vessel was then transferred to the freezing compartment of a refriger- 

 ator or a deep freeze and the water was frozen solid. All specimens which 

 have been tried have shown not the slightest tendency to contract or to 

 disengage parts. Upon removal from the freezer I have added alcohol at 

 times and formaldehyde (4 percent) at other times. In either case, as melt- 

 ing proceeded, nothing happened to the specimens; they were killed in the 

 same attitude in which they were frozen. 



In view of the simplicity of the process it is interesting to speculate 

 upon the possibility of using it for gastropods and such marine animals 

 as sea anemones which are prone to contract upon the slightest provocation. 



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