They are walnuts (https://en.wikipedia.org/wiki/Walnut) which are still not ripe and the nuts are inside the green outer skin.
Thank you so much that you like my little squirrel, @qwerrie, not I have to go back there and hope I'll see this little guy again, or maybe his family 😉
To give a !DERANGED and a !BEER is an easy and simple way for me to say thank you for being nice, and giving an additional !MARLIANS or !COFFEEA means I thank you even more 😉
