External Firewire Drives aren't recognised via firewire Hub

Hey!
thanks!
No that is not the case.
I have a MacBookPro and just 1 Fw SLot.
My Firewire external harddrives work perfectly,when connected directly to the fw-slot- but wont work at all when connected to the Fw/usb-hub.


So, is there maybe a different option than a fw-hub?
like a Firewire adapter for the Sd-Card slot or something like this?