Nature Watch: the bizarre butterfly

[callmemadam]

Amazingly, after the horrors of yesterday, the weather is mild and sunny today. I was just about to Hoover in the spare bedroom (housework has been much neglected, lately), when I saw a tortoiseshell butterfly basking on the bed. It wasn’t at all keen to be caught in the spider catcher and I of course wasn’t keen on damaging its delicate wings. At last I caught and released it, knowing that there are still nectar-providing plants outside. The mystery is: how did it get in, when windows have been firmly closed against the weather?