Jean-Louis kind of speaks incorrectly here when he says "Very old-timers will remember the pre-Mac File system called The Flounder", unless by old-timers he means Apple employees that were on the Mac team.
There's a little more about the early Mac software history at Folklore.org, including another screen shot of what eventually became Finder:
Funny... I converted Cream 12 for use in Apple II programs.
For the old-timers, it was a shape table and multiple draw commands of numbered (ascii value - 32) shapes would allow you to write proportionally spaced text to the graphical screen. It was the same format Take-1 used (we used their programmer's toolkit).
So, Cream 12 came down from Altos all the way to our Apple II+'s.
There's a little more about the early Mac software history at Folklore.org, including another screen shot of what eventually became Finder:
http://www.folklore.org/StoryView.py?project=Macintosh&story...
http://www.folklore.org/StoryView.py?project=Macintosh&story...