foldername

    Specifies the name of the folder from which to select messages.

    If you omit the foldername, the folder to be used is determined
    in the following order:

    1. The current folder is used, if any (unless the /NEW qualifier
       is specified)

    2. The NEWMAIL folder is used if:

       o  You specify the /NEW qualifier

       o  You omit selection qualifiers and you have new mail

    3. The MAIL folder is used.

 message-number

    Indicates the number of the message to be read. The message
    number represents the position of a message in a folder. If
    you specify a number greater than the number of messages in the
    folder, Mail displays the last message in the folder. Therefore,
    to read the latest message in a folder, specify a large message
    number or enter the LAST command.