That is a scan from my 35mm Kodak Tri-X negative. It had been stored in my little house in Mississippi and unfortunately some little critter really liked the gelatin on the Tri-X.
Here’s what a closeup of the area around Susan’s right foot looks like, with the tones adjusted to really show off the tracks these negative eating weasels left:
These are very much like the tracks one gets from critters crawling around the agar in a petri dish. Yay.
And here’s round one of a restoration attempt: