The mother load

So the open day went well and our owl pellet dissection was a big hit.  The kids loved sifting through the morbid remains of mice, voles and shrews.  Exhausting day though.  Whilst catching a breather from making sure children weren't eating miniature skulls and pelvis bones or poking each other in the eye with tweezers, we spotted this spider on one of the bags...

Not sure, but think its a nursery-web spider.  It was carrying its egg sack.  God, I hope this one didnt come home with me!!