The Knot grass moth caterpillar

I found this caterpillar last year crawling on a bit of bare ground in the garden.  It was a day of high winds, just like we've had the past two days, so I presumed it had got blown off its foodplant.  I took it in with a few leaves off the surrounding plants to try to identify it, but it wouldn't eat any of them, and I couldn't identify it, so after I photographed it I put it back where I'd found it.

It was only a few days ago while reading a book on woodland insects that I came across it's picture, and so was able to identify it at last, and add it to one of the Noctuid pages.