We use a variation of what Matthew suggested, as we are interested
_only_ in removing the cerebellum. We also insert the scissors into the
foramen magnum, but we cut around the cerebellum: we start the cut
heading rostral but as soon as we clear the cerebellum we start cutting
upwards towards the midline. Once reaching or slightly crossing the
midline we place the same cut for the other side, freeing the part of
the skull covering the cerebellum. Now one can use a forceps to remove
this part of the skull - if you grab the skull at the point where your
two cuts met and pull it off "tailwards" or grab hold of it at the
foramen magnum and pull the skull of in an upward-rostral direction (my
personal preference when working with rats) is a matter of taste.
Using this procedure you will normally destroy large parts of the
Cortex, so if you would want to prepare slices from several regions you
would need to vary it - probably Matthew's approach is the best for
Sorry, if I'm not making myself clear enough - I'll see if I can get a
picture series of a prep if I've totally lost you here.