Narcotisation, fixation and preservation experiments with marine zooplankton

In this report narcotisation, fixation and preservation experiments with marine zooplankton are described. Narcotisation turns out to be useless for mixed plankton samples. M.S. 222 works well as narcotisation medium for organisms to be photographed. Fixation with 4% formalin proved to be a necessary treatment. Afterwards the best preservation method is to use a propylene phenoxetol plus propylene glycol solution in distilled water or a 2% formalin solution in filtered seawater. Further study is necessary of the use of sea-water as a solution medium, of the pH changes, the osmotic value of the solutions, the longterm use and the subsequent processability of the organisms for histological purposes.