What's the yellow thing?

[Hades200082]

I got this piece because of the green mushrooms on it but didn't notice the yellow things til I got it home.

Can anyone tell me what they are and if they should be there or not?

thanks

 

[muttley000]

can you get a closer picture?

 

[parrotchute]

possibly sponges, hard to tell

 

[dwculp]

Looks like a sponge or maybe tunicates.

 

[Korrine]

Don't know what they are for sure, I'm thinking they aren't bad. Try to get a closer picture or crop and zoom

 

[BANANAHANDS]

+1 for sponges.