Can't see if the stalk is fluted, but they might be one of the Helvellas - you got trees nearby?

Stalks don't seem to be fluted - just straight up and down. They are on a tree-lined driveway in lots od shade.

If they're not helvella, then I don't know what they are, but helvella lacunosa and other helvellas do grow in association with tree roots in certain areas. They're harmless, and have a good association with trees, rather than an attacking one.

I've looked various helvellas up on the net and they certainly look similar. There seems to be loads of different varieties. Thanks for that.

Try H. lacunosa