I once used gnome-mount like this
gnome-mount -o ro -d /dev/sda2 or gnome-mount -o ro -p "Macintosh HD"
But, alas, gnome-mount seems to be no more. RIP.
I can do this
gvfs-mount -d /dev/sda2
(which generates a whole lot of errors but does mount the partition in the /media directory.)
This is a related question: Gnome-mount alternative in Ubuntu 10.04 or how to mount partition with normal user rights
But how do you do it by name?