I was able to digitally re-assemble all this gorgeous underwater Silly Symphony background art, except for that stubborn cartoon starfish, which was of course a cel overlay. Here's the full pan B/G:
Left side detail:
Middle detail:
Right side detail:
two restored standard frame size B/Gs:
A truly fantastic pan b/g:
Left side "stage" detail:
and some additional digitally re-created pan b/g masterpieces: