Brimstone  (Gonepteryx rhamni)

For more on butterflies, their conservation and details of how to get involved see: Butterfly Conservation:
http://www.butterfly-conservation.org.uk

For more on butterflies see: The Millennium Atlas of Butterflies in Britain and Ireland by: Asher, J., Warren, F., Fox, R. Harding, P., Jeffcoate, G. & Jeffcoate, S. Published by Oxford University Press.