I've used Chloral Hydrate and Menthol crystals (not at the same time)  with
pretty good results.  Place your mollusks in a container of seawater and
sprinkle crystals over the top of the water.  Do not disturb them.  If they
do not 'relax' in 24 hrs or so, put a little more on them.  It will take
some experimentation before you get the combination correct for each
species.  It also depends on variables such as temperature (air
conditioning in room or not), etc.
 
There is a paper in Malacological Review, I think in the 1980's on
relaxation techniques (not yoga, etc.) for the Muricidae.  Anybody out
there have that reference?
 
Kurt
 
At 04:27 PM 3/24/99 +1100, you wrote:
>I need information of narcotization of marine moluscs, for analized
>them  relaxeds
>