Friday afternoon on my way home. Suddenly there was a loud crack and an impact as something hit my helmet. Thinking at first that it sounded woody I reasoned that it was a twig, fter all I was under trees when it happened and so cycled on. I'd only gone a few metres when I realised the 'twig' was moving and then I got a stinging pain, at which point I stopped, took my helmet off and out fell a bumblebee. I did'nt think they could sting, but evidently they do even though the effects are fairly mild compared with normal bee/wasp stings.