I like your explanation of light (maybe luminescent) colored fungi growing on the bottom side of the hole. Maybe he could give it a different color...
edit - my pics -- no problem, Cliff - my original pics were so compresed, they looked tiny and horrible so I removed them and went and redid them to try to make them look bigger. First screensaved in bmp, then cropped out the portion I wanted to show in Irvanview and saved in bmp, then edited them in Paint and resaved as bmp and then Easy Thumbnailed them to fit the forum's size requirement in jpg. Bunch of compressions. Took some time. Your pics look nice as usual.