Leigh should know... she mailed me 6 or so from the east coast to the west
coast (during the summer btw) and they made it fine!
I would be a little cautious, mailing in summer. If the temperature's in the
90s, don't mail snails. Tried it once, and they didn't make it, even for a
short trip. :-(
They will tolerate a few days or weeks of cold, as long as temps remain above
freezing.
Leigh
http://www.fortunecity.com/lavender/halloween/881/