There are many ways to find the filesystem of a partition in linux (provided the partition mounted)
Following are the command line tools run these commands as is in terminal.
1. cat /etc/fstab
2. cat /etc/mtab
3. mount
4. df -T
Note: You should know the partition number (like /dev/sda2, /dev/sda4 etc.,) or the partition label (Like mypendrive, 8GB_drive etc.,) or the UUID number.
Following are the command line tools run these commands as is in terminal.
1. cat /etc/fstab
2. cat /etc/mtab
3. mount
4. df -T
Note: You should know the partition number (like /dev/sda2, /dev/sda4 etc.,) or the partition label (Like mypendrive, 8GB_drive etc.,) or the UUID number.