Sacha wrote:

On 2013-08-21 12:13:55 +0100, CT said:

Sacha wrote:

It's a Postman Butterfly:
http://en.wikipedia.org/wiki/Heliconius_melpomene

How terrific of you and Stewart to come up with that so quickly.
Thank you very much indeed. It says that it's poisonous but not to
what! Man, birds, other insects? Only other butterflies, I wonder?
I'll do some more looking up. The Nursery team will be thrilled to
know about it. We have quite a lot of passion flowers in various
greenhouses, so that could explain how it found its way to us. Thank
you very much!

I did cheat a little.

I'd been to the "Butterflies in the Glasshouse" at RHS Wisley earlier
in the year and that looked vaguely familiar so I Googled for their
Butterfly ID sheet that they gave out at the time and found this:
http://www.bbc.co.uk/news/uk-england-surrey-20992861

See the 4th image!

--
Chris