yes you can. remove any 'stuff' from around them and layer them between a couple of sheets of kitchen towel. when they are dry store them in an envelope until next spring. They may not be identical to the parent but they will be edible.

Wow, marrow for breakfast lunch and dinner this time next year then.
Thank you for replying, now i know.

John

yes they can be like that. pick small ones and treat as courgettes too.

To be honest we love them. We cook them until soft and blend them together with a little of the water and some soft cheese with a little salt and freshly ground black pepper.
It makes a lovely puree, although i must try out some different recipes soon, it was a huge marrow and there's only so much puree you can eat.