what is this growing up my leather?

[teena]

it started out at the bottom & is working its way to the top, its been growing for months, when the leather is down its the same color, but when its open like it is now you can see it better, heres a pic,

 

[teena]

 

[neuroslicer]

Looks porous... so I'd say it's a Poriferan. Hard to tell from the pic.


(a sponge... it's harmless).


Jay