Can you guess what it is yet?

I rarely post my own photos and the picture opposite is the reason why I tend to stick to field notes! Shameful isn't it? Really need to get a lens for my camera soon.

A coconut for anybody who can actually guess what it is. The only clue I'll give you (apart from the very obvious one above) is that it was on Predannack Airfield, I found it today and it is a long overdue self-found lifer for me. Actually the first I've had since moving to Cornwall.