Strange substance growing on broad bean and pea seeds

Evening all, first post

My broad bean and pea seeds are each growing in individual cells. They are coming along nicely and looking very healthy, but when I pulled one out today there was a strange white substance growing on the outside of the seed. It's not furry, seems to be more fungus like. 

The leaves, stem and roots are all fine, as is the vast majority of the actual seed, it just seems to be the skin of the seed that is affected. I've never come across this before, just wondering if this is something I should worry about, or possibly some sort of naturally occurring 'good fungus' 

Any help would be much appreciated.

Thanks in advance