SOME RECENT METHODS FOR NARCOTIZATION, KILLING, 

 FIXATION, AND PRESERVATION OF MARINE ORGANISMS. 



Appendix I,. (1) Propylene Phenoxetol. 



(2) Sevin and Rapid Freezing M. R. Carriker 



(1) Propylene phenoxetol ; for many bivalves, particu- 

 larly those in which the valves do not close tightly; for 

 gastropods in which the shell is wanting; and for some tuni- 

 cates. It is important that the narcotic have access to the 

 soft parts; in the case of tightly-closing bivalves this can 

 be facilitated by pegging the valves open with slivers of 

 wood while the animals are siphoning actively. 



Narcotization may be accomplished by either of the 

 following two ways: (a) Shake 5 ml of propylene phenoxetol 

 in 15-20 ml of seawater to produce a fine emulsion and add 

 this to a small quantity of still seawater containing the 

 actively siphoning specimens. Within a half hour or so 

 animals should be completely relaxed and may be fixed in this 

 condition without causing any contraction of the tissues, 

 (b) Add the phenoxetol (a quantity not to exceed 1% of the 

 volume of seawater present) gently to the vessel of still 

 seawater containing the animals, so that it cdllects as a 

 globule on the bottom of the container. Organisms may be 

 left in the solution overnight and should be well relaxed 

 at the end of this period. Histological sections of animals 

 treated in this way show no deterioration of the tissues and 

 no loss of staining properties; and narcotized animals if 

 washed and placed in fresh seawater, recover and appear to 

 function normally (Owen 1955) . 



Killing , fixation , and preservation : Kill and fix 

 narcotized animals in 10% neutralized formalin (200 g of 

 hexamine per liter of commercial formalin: Smith, 1947) 

 for 4 to 24 hours, depending upon the size of the specimens 

 and inject the formalin into the body cavity of larger animals 

 to insure good fixation and to help distend them. Wash 

 preserved animals thoroughly in running tap water for 6 to 12 

 hours, depending on size and preserve them permanently in 1% 

 propylene phenoxetol and 5-10% glycerol . Particular advantages 

 of propylene phenoxetol as a preservative: is colorless, 

 practically odorless, color retention in specimens is good, 

 and tissues remain soft and flexible and suitable for dissection 

 (Owen & Steedman, 1958) . The method may also be useful for 

 other invertebrates lacking an exoskeleton and is worth 

 attempting. 



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