Ah Nuts!

said the squirrel. I took some photos of these same... nuts... yesterday but they were full green shells, so either a squirrel has been having a go or they are hatching.... but I am going to show my ignorance... there were only trees around where they fell but I can't find out what they are from google... if they were acorns, they'd have a crown? I've spent too long googling it, so leaving it for a real person to put me out of my misery! Anybody? Class?