Tom, et al:
The address you gave is correct, but the listserv command is not.
The command you mentioned "SET CONCH-L NOMAIL" is to temporarily
suspend your mail, for example while you are on vacation.
The command to unsubscribe is "SIGNOFF CONCH-L"
As Tom said, this message should be sent to
"[log in to unmask]",
NOT to Conch-L.
Paul M