It's there, you can check it yourself by downloading MorphOS ISO.

MOSSYS: is only for system components and it shouldn't be generally touched by the user. For all other stuff there is SYS:

Q: What is MOSSYS: and SYS:MorphOS?
A: MOSSYS: is an assign pointing to SYS:MorphOS. The idea is that SYS:MorphOS is a private directory for the operating system and you don't need to touch anything in it. A system upgrade will be done by simply putting a new directory (old one can be renamed or so). If you want to change the way the system is started edit s:user-startup, nothing else.

[ Edited by Korni 18.03.2012 - 17:29 ]