For what it is worth, I have had several opportunities to collect landsnails
after forest fires; a collecting technique suggested to me by a USDA Forest
Service biologist.  (For the cynical, no I did not set the fires.)  I have
been amazed at the incredible numbers of landsnails which are clearly visible
in the charred aftermath.  Most shells are brittle to the touch to the point
of becoming ash when touched, but a surprising number manage to be caught in
small crevices, etc. during the fires.  It is not enough to spare the animal,
but occasionally it is enough to spare the shell and often the periostracum.
I have several lots of specimens collected from such localities.  Has anyone
else ever collected in this manner?
 
Doug Shelton
Alabama Malacological Research Center
2370-G Hillcrest Road #236
Mobile, AL  36695